Updated on 2024/10/09

Information

 

写真a

 
LIU HUIXIN
 
Organization
Faculty of Science Department of Earth and Planetary Sciences Professor
Faculty of Science Superheavy element research center（Concurrent）
Office for the Promotion of Gender Equality （Concurrent）
International Center for Space and Planetary Environmental Science （Concurrent）
School of Sciences Department of Earth and Planetary Sciences（Concurrent）
Graduate School of Sciences Department of Earth and Planetary Sciences（Concurrent）
Title
Professor
Profile
1. Research: Vertical coupling in the Earth's atmosphere Vertical coupling in the Earth’s atmosphere from the ground surface to the topside (1000 km), in terms of both neutral-neutral and plasma-neutral interaction, is an essential aspect for the Sun-Earth connection. It holds the key to further advance the current climate and weather predictions. On this solar-terrestrial chain, the thermosphere is a critical region in linking the lower and upper atmosphere. My research focuses on the thermosphere/ionosphere and their dynamic and chemical coupling to other atmospheric regions. Such research functions as a natural catalyst for spurring multi-disciplinary research activities, which enable us to cross the science boundaries between meteorology and space science in particular, between physics and chemistry in general. Thus, by enhancing the scientific and educational contacts, it will help to strengthen the ties among various divisions in the Faculty of Science and foster mutual improvements. Current and past topics: -Ion-neutral interaction in the thermosphere and ionosphere: equatorial mass density anomaly and wind jets - The thermosphere/ionosphere longitudinal variation: Wave-4 structure and coupling with lower atmosphere - How does the thermosphere respond to Stratosphere sudden warmings? - How does El Nino Southern Oscillation (ENSO) affect MLT region tidal activity? - Modelling global warming effect on the upper atmosphere 2. Education Teach atmospheric physics and plasma physics course to both undergraduate and graduate students. Depends on students' level, some courses are taught in English, and some are in Japanese. 3. Social activity: - Panel reviewer for national science foundations and space agencies (NSF (US), NASA (US), Canadian NSF, JSPS, etc.) - Editor for science journals: Space Weather (AGU 2018~), Ann. Geophyicae (EGU 2017~), Earth, Planets and Space (SGEPSS 2016~) - Global engagement committee member for American Geophysical Union (2018~) - Executive committee member for CEDAR/NSF, USA (2019~) - Executive committee member for IAGA (2019~) - Global Strategy Committee member for JPGU (2020~) - Convener at international meetings like AGU (american geophysical union), AOGS, and JpGU. - Science program chair for joint JpGU-AGU meeting in 2017. - SGEPSS's Mesosphere-thermosphere-ionosphere (MTI) working group organizer (2009~2013) - SGEPSS member, AGU member, EGS member - Frequent reviewer of JGR, GRL, Ann. Geo, Science
Homepage
External link

Research Areas

  • Natural Science / Space and planetary sciences

  • Natural Science / Space and planetary sciences

Degree

  • Doctor of Science

Research History

  • Kyushu University Faculty of Sciences Professor 

    2023.12 - Present

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  • Kyushu University Earth and Planetary Science Associate Professor 

    2011.5 - 2023.11

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Research Interests・Research Keywords

  • Research theme： Ionosphere

    Keyword： Ionosphere

    Research period： 2024

  • Research theme： magnetic storms

    Keyword： magnetic storms

    Research period： 2024

  • Research theme： thermosphere composition and dynamics

    Keyword： thermosphere composition and dynamics

    Research period： 2024

  • Research theme： Space weather

    Keyword： Space weather

    Research period： 2024

  • Research theme： satellite drag and orbital control

    Keyword： satellite drag and orbital control

    Research period： 2024

  • Research theme： Atmosphere-ionosphere coupling

    Keyword： Atmosphere-ionosphere coupling

    Research period： 2024

  • Research theme： Vertical coupling in the atmosphere

    Keyword： Vertical coupling in the atmosphere

    Research period： 2024

  • Research theme： plasma-neutral interaction

    Keyword： plasma-neutral interaction

    Research period： 2024

  • Research theme： Formation machoism of Sporadic E

    Keyword： vertical coupling, thermosphere, ionosphere,Sporadic E

    Research period： 2021.11 - 2024.3

  • Research theme： Wave coupling processes of the middle and upper atmosphere: Interannual and long- term variability (JSPS-DFG international joint project)

    Keyword： vertical coupling, thermosphere, ionosphere, troposphere, long-term trend, inter annual variation

    Research period： 2019.3 - 2024.3

  • Research theme： Response of the upper atmosphere to El Nino Southern Oscillation (ENSO)

    Keyword： vertical coupling, thermosphere, ionosphere, troposphere, ENSO

    Research period： 2018.4 - 2024.3

  • Research theme： ENSO effect on the upper atmosphere: the role of O3

    Keyword： vertical coupling, thermosphere, ionosphere, troposphere, ENSO, Ozone layer

    Research period： 2018.4 - 2023.3

  • Research theme： Exploring the role of gravity waves in seeding equatorial plasma bubbles

    Keyword： thermosphere, ionosphere, atmospheric gravity waves, ionospheric irregularities, equatorial plasma bubble

    Research period： 2018.4 - 2020.3

  • Research theme： Response of the upper atmosphere to El Nino Southern Oscillation (ENSO)

    Keyword： vertical coupling, thermosphere, ionosphere, troposphere, ENSO

    Research period： 2015.4 - 2018.3

  • Research theme： Ionospheric Current system observed by the CHAMP satellite

    Keyword： thermosphere, ionosphere, ionospheric current system

    Research period： 2012.4 - 2015.3

  • Research theme： Response of the upper atmosphere to stratosphere sudden warming

    Keyword： vertical coupling, thermosphere, ionosphere, stratosphere

    Research period： 2012.1 - 2014.8

  • Research theme： Coupling of the Earth's atmospheric layers: interactions between the ionosphere, thermosphere and mesosphere in the Sun-Earth system

    Keyword： vertical coupling, thermosphere, ionosphere,

    Research period： 2009.4 - 2012.3

Awards

  • 田中館賞 (Tanakadate award for distinguished scientist)

    2023.5   地球電磁気・地球惑星圏学会   Research on vertical coupling from troposphere to upper atmosphere using satellite observations and model simulations

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    [高精度加速度計搭載低軌道衛星観測・ GCM シミュレーションを用いた対流圏から超高層 大気までの上下結合の研究]による受賞
    地球の超高層大気(熱圏や電離圏)は、下層大気 と宇宙空間からの影響をうけて大きく変動してい ます。Huixin Liu 会員は、人工衛星に搭載された 高精度加速度計による観測と、世界最先端の大気 圏・電離圏モデルシミュレーションを駆使した総 合解析による研究を実施することにより、今まで 知られていなかった下層大気からの影響による超 高層大気変動を次々に明らかにしてきました。成 層圏突然昇温(SSW)に伴って中間圏では降温、熱圏 下部(100-200 km)では昇温となることが知られて いましたが、Liu 会員は、大規模 SSW の際に高度 200 km 以上の熱圏では降温の結果として大気質量 密度が減少することを見出しました。また、エル ニーニョ・南方振動(ENSO)に伴う熱圏・電離圏の 4-6 年周期変動や、大気潮汐の変動などを初めて 明らかにしました。さらに、電離圏の大振幅のプ ラズマ不安定現象であるプラズマバブルの発生に 対して、対流圏を起源とする大気重力波が関与し ている証拠を明らかにしました。また、地球温暖 化の原因となる CO2 増加が引き起こす超高層大気 の寒冷化に伴う熱圏の風速や大気波動の振幅の変 化などを、大気圏・電離圏結合モデルシミュレー ションを用いて初めて明らかにしました。
    Liu 会員は、NASA や NSF などの審議員、国際誌 3 誌の Editor、IAGA や CEDAR の理事、AGU の国際 委員など、国際学術コミュニティの発展にも尽力 されています。また、本学会の MTI 分科会の世話 人や、2017 年の JpGU・AGU 合同大会のサイエンス プログラム委員長をはじめとした数多くの国際会 議のコンビーナを務められるなど、日本の地球惑 星科学の発展と国際化の推進にも尽力されていま す。以上のように Liu 会員は、超高層大気物理学 の分野において、学際的かつ国際的な研究をリー ドして大きな学術的貢献をされてきましたので、 田中舘賞受賞に値すると判断いたしました。

  • Tanakadate Medal

    2022.10   Society of Geomagnetism of Earth, Planetary and Space Science  

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  • 地球惑星科学振興　西田賞 (JpGU Nishida Award)

    2019.4   日本地球惑星科学連合   Research on the vertical coupling between the atmosphere and ionosphere using high-precision satellite observations and whole atmosphere models

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    Huixin Liu氏は人工衛星による超高層大気観測と全球数値シミュレーションを駆使した地球の全大気の総合解析を通じて世界最先端の大気・プラズマ結合研究を推進している。高精度加速度計を世界に先駆けて熱圏の観測に活用することで熱圏密度異常と熱圏風ジェットなどの大規模構造を発見し、磁場が中性大気の振る舞いを支配することを初めて明らかにした。また、大磁気嵐と太陽フレアに対する超高層大気の多様性とその多様性を生じるメカニズムを明らかにし、宇宙天気分野の進展に大きく貢献した。更に、成層圏突然昇温が引き起こした熱圏冷却現象とエルニーニョによる超高層大気の経年変動を発見し、全球数値シミュレーションによって下層大気に起源をもつ潮汐波や大気重力波が超高層大気に影響を与える物理機構を定量的に示すことで、気象現象と宇宙現象の繋がりを明らかにした。以上のように太陽・地球系における大気圏、熱圏、電離圏の領域間「結合過程」に注目したHuixin Liu氏の顕著な研究業績は、世界的に高く評価されている。

  • 地球惑星科学振興 西田賞

    2019.4   日本地球惑星科学連合   JpGU Nishida Award

  • 資生堂 女性研究者サイエンスグラント (Shiseido Science Grant)

    2013.6   資生堂   成層圏から超高層まで：成層圏突然昇温に対する超高層大気寒冷化の生成機構の解明

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    成層圏から超高層まで:成層圏突然昇温に対する超高層大気寒冷化の生成機構の解明。北極域で発生する成層圏突然昇温気象現象が赤道域の大気まで影響する物理過程を発見した。

  • 女性研究者サイエンスグラント

    2013.6   資生堂株式会社   Shiseido Science Grant

  • 文部科学大臣表彰若手科学者賞 (Japan MEXT distinguished young scientist award)

    2012.4   文部科学大臣   衛星加速時計観測による下層大気と熱圏と電離圏結合の研究

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    衛星加速度計データを用いた下層大気—熱圏—電離圏結合の研究

  • 文部科学大臣表彰若手科学者賞

    2012.4   文部科学省   Japan MEXT distinguished young scientist award

  • 大林奨励賞 (Obayashi Medal for distinguished young scientist)

    2010.11   地球電磁気・地球惑星圏学会   Research on the thermosphere-ionosphere interaction using satellite-bourne accelerometer observations

  • 大林奨励賞

    2010.11   地球電磁気・地球惑星圏学会   Obayashi Medal for distinguished young scientist

  • JSPS RPD Fellowship (Japan)

    2009.4   Japan Socient for the Promotion of Science (Japan)   Plasma-neutral interaction in the mesosphere-thermosphere-ionosphere system

  • RPD Fellow

    2009.4   日本科学振興会   RPD Fellow

  • JSPS foreign scholar Fellowship (Japan)

    2006.10   Japan Socient for the Promotion of Science (Japan)   The Thermosphere-Ionosphere Coupling at Low Latitudes

  • JSPS fellow (foreign)

    2006.10   日本科学振興会   JSPS fellow (foreign)

  • Alexander von Humboldt Fellowship (Germany)

    2004.5   Alexander von Humboldt foundation (Germany)   Global Thermosphere-Ionosphere coupling study base on CHAMP satellite observations

  • Alexander von Humboldt Fellowship

    2003.8   ドイツ Alexander von Humboldt foundation   Alexander von Humboldt Fellowship

  • German DAAD Fellowship for academic exchange

    1998.10   German Academic Exchange (DAAD) foundation   Studying the polar ionosphere response to magnetic storms with the international EISCAR radar system

  • DAAD Fellowship for academic exchange

    1998.10   ドイツGerman Academic Exchange (DAAD)   DAAD Fellowship for academic exchange

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Papers

  • Altitude extension of NCAR-TIEGCM (TIEGCM‑X) and evaluation Reviewed

    Yihui Cai, Xinan Yue, Wenbin Wang, Shun‑Rong Zhang, Huixin Liu, Dong Lin, Haonan Wu, Jia Yue, Sean L. Bruinsma, Feng Ding, Zhipeng Ren, Libo Liu

    Space Weather   2023.5

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    Language：Others   Publishing type：Research paper (scientific journal)  

    DOI： 10.5194/egusphere-egu23-12894

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  • Low Altitude Tailing Es (LATTE): Analysis of Sporadic-E Layer Height at Different Latitudes of Middle and Low Region Reviewed International journal

    1. Tang, Q., C. Zhou, Huixin Liu,

    Space Weather   2023.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1029/2022SW003323

  • Impact of Tropospheric Ozone Modulation Due To El Niño on Tides in the MLT Reviewed International journal

    Masaru Kogure, Huixin Liu, Hidekatsu Jin

    Geophysical Research Letters   50 ( 6 )   2023.3   （ ISSN:0094-8276 eISSN:1944-8007 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Geophysical Research Letters  

    To assess the impacts of the tropospheric ozone modulation due to El Niño on tides, we performed two simulations by using the Ground-to-topside Atmosphere Ionosphere model for Aeronomy model: zonally symmetric ozone density and longitudinal ozone variation of an El Niño pattern. Our results show that the ozone modulation strengthens (attenuates) the first symmetric mode of the DW2 (D0 and DW1) tide by ∼+5% (∼−1% and ∼−4%) from ∼20 to ∼100 km altitudes on average. These responses are probably attributed to the tropospheric ozone modulation. These responses are reasonable because both the ozone modulation and these first modes have a peak at the equator. Also, the vertical wavelengths of the first modes are about twice as long as the vertical thickness of the ozone modulation. Our results suggest that the ozone modulation due to El Niño influences the diurnal tides by a few percent because of the ozone modulation spatial structure.

    DOI： 10.1029/2023GL102790

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  • Determining the Origin of Tidal Oscillations in the Ionospheric Transition Region With EISCAT Radar and Global Simulation Data

    F. Günzkofer, D. Pokhotelov, G. Stober, H. Liu, H.‐L. Liu, N. J. Mitchell, A. Tjulin, C. Borries

    Journal of Geophysical Research: Space Physics   127 ( 10 )   2022.10   （ ISSN:2169-9380 eISSN:2169-9402 ）

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    Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Journal of Geophysical Research: Space Physics  

    At high-latitudes, diurnal and semidiurnal variations of temperature and neutral wind velocity can originate both in the lower atmosphere (UV or infrared absorption) and in the thermosphere-ionosphere (ion convection, EUV absorption). Determining the relative impact of different forcing mechanisms gives insight to the vertical coupling in the ionosphere. We analyze measurements from the incoherent scatter radar (ISR) facility operated by the EISCAT Scientific Association. They are complemented by meteor radar data and compared to global circulation models. The amplitudes and phases of tidal oscillations are determined by an adaptive spectral filter (ASF). Measurements indicate the existence of strong semidiurnal oscillations in a two-band structure at altitudes ≲110 and ≳130 km, respectively. Analysis of several model runs with different input settings suggest the upper band to be forced in situ while the lower band corresponds to upward-propagating tides from the lower atmosphere. This indicates the existence of an unexpectedly strong, in situ forcing mechanism for semidiurnal oscillations in the high-latitude thermosphere. It is shown that the actual transition of tides in the altitude region between 90 and 150 km is more complex than described so far.

    DOI： 10.1029/2022JA030861

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  • Global Structure and Seasonal Variations of the Tidal Amplitude in Sporadic‐E Layer Reviewed

    Qiong Tang, Chen Zhou, Huixin Liu, Zhitao Du, Yi Liu, Jiaqi Zhao, Zhibin Yu, Zhengyu Zhao, Xueshang Feng

    Journal of Geophysical Research: Space Physics   127 ( 10 )   2022.10   （ ISSN:2169-9380 eISSN:2169-9402 ）

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    Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Journal of Geophysical Research: Space Physics  

    The Constellation Observing System for Meteorology, Ionosphere, and Climate radio occultation S4 indices measurements are used to investigate the global structure and seasonal variations of tidal components in the sporadic-E (Es) layer. The diurnal tidal amplitude in the Es layer intensity and occurrence rate shows a wave-4 longitudinal structure, which is due to the diurnal tidal components of zonal wave numbers s = −3 (eastward, DE3). The wave-4 longitudinal pattern is also observed in the semidiurnal tide during spring and winter, which mostly results from the combination of semidiurnal components of zonal wave numbers s = −2 (eastward, SE2), s = 2 (westward, SW2). In addition, the semidiurnal tidal amplitude in Es layers presents obvious seasonal variability, and it dominates in the northern hemisphere during spring and summer and in the southern hemisphere during autumn and winter. Furthermore, the total semidiurnal tidal amplitude in Es layers in the northern hemisphere is greater than that in the southern hemisphere. Another important finding is that the diurnal tidal pattern at the lower altitude (below 102 km) Es layer is different from that of the higher altitude (above 102 km) Es layer and is also different from that of wind, which supports that the wind shear theory is inapplicable for the Es layer formation at low altitude proposed by many researchers.

    DOI： 10.1029/2022JA030711

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  • Latitudinal Dependence of the Geomagnetic and Solar Activity Effect on Sporadic-E layer

    Qiong Tang, Chen Zhou, Huixin Liu, Yi Liu, Jiaqi Zhao, Zhibin Yu, Zhengyu Zhao, Xueshang Feng

    2022.9

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    Language：Others  

    DOI： 10.5194/acp-2022-534

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  • Mechanisms for Zonal Mean Wind Responses in the Thermosphere to Doubled CO 2 Concentration

    Masaru Kogure, Huixin Liu, Chihiro Tao

    Journal of Geophysical Research: Space Physics   2022.9

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    Language：Others   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2022JA030643

  • Determining the origin of tidal oscillations in the ionospheric transition region with EISCAT radar and global simulation data Reviewed

    Florian Ludwig Günzkofer, Dimitry Pokhotelov, Gunter Stober, Huixin Liu, Han-Li Liu, Nicholas John Mitchell, Anders Tjulin, Claudia Borries

    Journal of Geophysical Research: Space Physics   2022.7

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    Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    DOI： 10.1002/essoar.10511964.1

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  • SpaceX—Sailing Close to the Space Weather? Reviewed International journal

    Mike Hapgood, Huixin Liu, Noé Lugaz

    Space Weather   20 ( 3 )   2022.3   （ eISSN:1542-7390 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Space Weather  

    The 3 February 2022 launch of 49 of SpaceX's Starlink satellites has provided a fascinating example of how even modest space weather can have significant practical and financial consequences. Enhanced atmospheric drag associated with a minor geomagnetic storm led to the loss of the majority of the 49 launched satellites. Although the 36th launch by SpaceX in the past 3 years, it was the first that experienced stormy space weather. We expect more stormy space weather as Solar Cycle 25 ramps up toward its peak expected in 2025. A subsequent Starlink launch on 21 February used a higher initial orbit at 300 km, reducing the payload from 49 to 46 satellites, and can be considered an agile response to the space weather losses experienced 2 weeks earlier. Lessons to be learned by the space industry and the space weather community are discussed, including a better dialog, nuanced understanding of space weather risks associated with modest events, but also an opportunity to investigate the space environment in relatively unexplored regions such as very low and high low Earth orbits.

    DOI： 10.1029/2022SW003074

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  • Thermospheric Density Perturbations Produced by Traveling Atmospheric Disturbances During August 2005 Storm Reviewed International journal

    K. H. Pham, B. Zhang, K. Sorathia, T. Dang, W. Wang, V. Merkin, H. Liu, D. Lin, M. Wiltberger, J. Lei, S. Bao, J. Garretson, F. Toffoletto, A. Michael, J. Lyon

    Journal of Geophysical Research: Space Physics   2022.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021JA030071

  • SpaceX - sailing close to the space weather? Reviewed

    Michael A. Hapgood, Huixin Liu, Noé Lugaz

    Space Weather   2022.2

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    Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    DOI： 10.1002/essoar.10510636.1

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  • Thermospheric Density Perturbations Produced by Traveling Atmospheric Disturbances During August 2005 Storm

    K. H. Pham, B. Zhang, K. Sorathia, T. Dang, W. Wang, V. Merkin, H. Liu, D. Lin, M. Wiltberger, J. Lei, S. Bao, J. Garretson, F. Toffoletto, A. Michael, J. Lyon

    Journal of Geophysical Research: Space Physics   127 ( 2 )   2022.2

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    Language：Others   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021JA030071

  • Ionospheric Topside Diffusive Flux and the Formation of Summer Nighttime Ionospheric Electron Density Enhancement Over Millstone Hill

    Yihui Cai, Xinan Yue, Wenbin Wang, Shun‐Rong Zhang, Huixin Liu, Jiuhou Lei, Zhipeng Ren, Yiding Chen, Feng Ding, Dexin Ren

    Geophysical Research Letters   49 ( 4 )   2022.2

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    Language：Others   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021GL097651

  • Ionospheric Topside Diffusive Flux and the Formation of Summer Nighttime Ionospheric Electron Density Enhancement Over Millstone Hill Reviewed International journal

    Yihui Cai, Xinan Yue, Wenbin Wang, Shun‐Rong Zhang, Huixin Liu, Jiuhou Lei, Zhipeng Ren, Yiding Chen, Feng Ding, Dexin Ren

    Geophysical Research Letters   2022.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021GL097651

  • The Possible Role of Turbopause on Sporadic‐E Layer Formation at Middle and Low Latitudes Reviewed International journal

    Qiong Tang, Chen Zhou, Huixin Liu, Yi Liu, Jiaqi Zhao, Zhibin Yu, Zhengyu Zhao, Xueshang Feng

    Space Weather   2021.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021SW002883

  • Superposed epoch analysis of coupling mechanisms captured by meteor radars during sudden stratospheric warmings Reviewed International journal

    Benedikt Gast, Ales Kuchar, Gunter Stober, Christoph Jacobi, Dimitry Pokhotelov, Huxin Liu, Han-Li Liu, Kathrin Baumgarten, Peter Brown, Diego Janches, Damian Murphy, Alexander Kozlovsky, Mark Lester, Evgenia Belova, Johan Kero, Nicholas Mitchell, Tracy Motffat-Griffin

    DACH   2021.12

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    Language：English   Publishing type：Research paper (bulletin of university, research institution)  

    DOI： 10.5194/dach2022-84

  • Long-term changes in mesospheric wind and wave estimates based on radar observations in both hemispheres Reviewed International journal

    Ales Kuchar , Gunter Stober , Christoph Jacobi , Dimitry Pokhotelov , Huxin Liu , Han-Li Liu , Kathrin Baumgarten , Peter Brown , Diego Janches , Damian Murphy , Alexander Kozlovsky , Mark Lester , Evgenia Belova , Johan Kero , Nicholas Mitchell , Tracy Motffat-Griffin

    DACH   2021.12

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    Language：English   Publishing type：Research paper (bulletin of university, research institution)  

    DOI： 10.5194/dach2022-81

  • Machine‐Learning Research in the Space Weather Journal: Prospects, Scope, and Limitations Reviewed International journal

    Noé Lugaz, Huixin Liu, Mike Hapgood, Steven Morley

    Space Weather   2021.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021SW003000

  • Climatology Analysis of the Daytime Topside Ionospheric Diffusive O + Flux Based on Incoherent Scatter Radar Observations at Millstone Hill Reviewed

    Yihui Cai, Wenbin Wang, Shun‐Rong Zhang, Xinan Yue, Zhipeng Ren, Huixin Liu

    Journal of Geophysical Research: Space Physics   2021.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021JA029222

  • Interhemispheric differences of mesosphere–lower thermosphere winds and tides investigated from three whole-atmosphere models and meteor radar observations Reviewed

    Gunter Stober, Ales Kuchar, Dimitry Pokhotelov, Huixin Liu, Han-Li Liu, Hauke Schmidt, Christoph Jacobi, Kathrin Baumgarten, Peter Brown, Diego Janches, Damian Murphy, Alexander Kozlovsky, Mark Lester, Evgenia Belova, Johan Kero, Nicholas Mitchell

    Atmospheric Chemistry and Physics   2021.9

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.5194/acp-21-13855-2021

  • DW1 Tidal Enhancements in the Equatorial MLT During 2015 El Niño: The Relative Role of Tidal Heating and Propagation Reviewed International journal

    Masaru Kogure, Huixin Liu

    Journal of Geophysical Research: Space Physics   126 ( 7 )   2021.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    Ground-based and satellite observations have shown that the tidal component DW1 in
    the equatorial mesosphere and lower thermosphere (MLT) was enhanced in July–October 2015, which was an intense El Niño year. This enhancement is reproduced in the 21 years reanalysis-driven model simulation by the Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy (GAIA). Our analysis shows the (1,1) Hough mode dominates this tidal enhancement, and its peak amplitude was 7.4 K (74%) higher than that under neutral (non-ENSO) conditions at 90 km. The corresponding tidal heating was found to increase by 0.4 mWkg−1 (5%), which can explain 0.5 K (7%) of the (1,1) enhancement. To explain the remaining 6.9 K (93%) of the enhancement, we quantitively examined the upward propagation condition by calculating the vertical wavenumber and the latitudinal shear of the zonal wind. The analysis reveals that the vertical wavenumber between 18 and 60 km was one standard deviation smaller than
    that under neutral conditions. The latitudinal zonal wind shear also decreased at 18 N/S° in 18–30 km. These results suggest smaller dissipation and damping of the (1,1) mode during its upward propagation, which dominantly contributed to the tidal enhancement at 90 km altitude. This decrease in the vertical wavenumber and the wind shear can be reasonably explained by the eastward phase of the quasi-biennial oscillation (QBO) in the lower stratosphere. This study suggests that the overlapping of the 2015 El Niño with the eastward phase of the QBO induced the large enhancement of the DW1.

    DOI： 10.1029/2021ja029342

  • Gravity Wave Weakening During the 2019 Antarctic Stratospheric Sudden Warming Reviewed

    Masaru Kogure, Jia Yue, Huixin Liu

    Geophysical Research Letters   48 ( 8 )   2021.4

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    DOI： 10.1029/2021GL092537

  • Day‐to‐Day Variability of the Thermosphere and Ionosphere Invited Reviewed

    Huixin Liu, Yosuke Yamazaki, Jiuhou Lei

    Space Physics and Aeronomy Collection Volume 4: Upper Atmosphere Dynamics and Energetics, Geophysical Monograph 261   275 - 300   2021.3

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    DOI： 10.1002/9781119815631.ch15

  • Sudden Stratospheric Warming Impacts on the Ionosphere– Thermosphere System: A Review of Recent Progress Invited Reviewed International journal

    Larisa P. Goncharenko, V. Lynn Harvey, Huixin Liu, Nicholas M. Pedatella

    Space Physics and Aeronomy Collection Volume 3: Ionosphere Dynamics and Applications, Geophysical Monograph 260   369 - 400   2021.3

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    Sudden Stratospheric Warming Impacts on the Ionosphere– Thermosphere System: A Review of Recent Progress

    DOI： 10.1002/9781119815617.ch16

  • The Characteristics of Summer Descending Sporadic E Layer Observed With the Ionosondes in the China Region Reviewed

    Lihui Qiu, Xiaomin Zuo, Tao Yu, Yangyi Sun, Huixin Liu, Lingfeng Sun, Biqiang Zhao

    Journal of Geophysical Research: Space Physics   126 ( 3 )   2021.3

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    DOI： 10.1029/2020JA028729

  • Geomagnetic activity effects on CO2-driven trend in the thermosphere and ionosphere: ideal model experiments with GAIA Reviewed International journal

    @Huixin Liu, C. Tao, H. Jin, #T. Abe

    J. Geophys. Res.   126   2021.1

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    DOI： 10.1029/2020JA028607

  • Geomagnetic Activity Effects on CO2 ‐Driven Trend in the Thermosphere and Ionosphere: Ideal Model Experiments With GAIA Reviewed

    Huixin Liu, Chihiro Tao, Hidekatsu Jin, Takamichi Abe

    Journal of Geophysical Research: Space Physics   126 ( 1 )   2021.1

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    We examine impacts of geomagnetic activity (GA) on CO -driven trend in the ionosphere and thermosphere using the Ground-to-topside Atmosphere Ionosphere model for Aeronomy whole atmosphere model. The model reveals three salient features. (1) Geomagnetic activities usually weakens the CO -driven trend at a fixed altitude. Among the IT parameters analyzed, the thermosphere mass density is the most robust indicator for CO cooling effect even with GA influences. (2) Geomagnetic activities can either strengthen or weaken the CO -driven trend in hmF2 and NmF2, depending on local time and latitudes. This renders the widely used linear fitting methods invalid for removing geomagnetic effects from observations. (3) An interdependency exists between the efficiency of CO forcing and geomagnetic forcing, with the former enhances at lower GA level, while the latter enhances at higher CO concentration. This could imply that the CO -driven trend would accelerate in periods of declining GA, while magnetic storms may have larger space weather impacts in the future with increasing CO . These findings provide a preliminary model framework to understand interactions between the CO forcing from below and the geomagnetic forcing from above. 2 2 2 2 2 2 2 2 2

    DOI： 10.1029/2020ja028607

  • The characteristics of summer descending sporadic E layer observed with the ionosondes in the China region Reviewed International journal

    L. Qiu, X. Zuo, T. Yu, Y. Sun, @Huixin Liu, L. Sun, B. Zhao

    J. Geophys. Res.   48   2021.1

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    DOI： 10.1029/2020JA028729

  • Dipolar elementary current systems for ionospheric current reconstruction at low and middle latitudes Reviewed

    Heikki Vanhamäki, Astrid Maute, Patrick Alken, Huixin Liu

    Earth, Planets and Space   72 ( 1 )   2020.12

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    <title>Abstract</title>
    The technique of spherical elementary current systems (SECS) is a powerful way to determine ionospheric and field-aligned currents (FAC) from magnetic field measurements made by low-Earth-orbiting satellites, possibly in combination with magnetometer arrays on the ground. The SECS method consists of two sets of basis functions for the ionospheric currents: divergence-free (DF) and curl-free (CF) components, which produce poloidal and toroidal magnetic fields, respectively. The original CF SECS are only applicable at high latitudes, as they build on the assumption that the FAC flow radially into or out of the ionosphere. The FAC at low and middle latitudes are far from radial, which renders the method inapplicable at these latitudes. In this study, we modify the original CF SECS by including FAC that flow along dipolar field lines. This allows the method to be applied at all latitudes. We name this method dipolar elementary current systems (DECS). Application of the DECS to synthetic data, as well as Swarm satellite measurements are carried out, demonstrating the good performance of this method, and its applicability to studies of ionospheric current systems at low and middle latitudes.

    DOI： 10.1186/s40623-020-01284-1

  • Ionospheric F Layer Scintillation Weakening as Observed by COSMIC/FORMOSAT‐3 During the Major Sudden Stratospheric Warming in January 2013 Reviewed

    Tao Yu, Hailun Ye, Huixin Liu, Chunliang Xia, Xiaomin Zuo, Xiangxiang Yan, Na Yang, Yangyi Sun, Biqiang Zhao

    Journal of Geophysical Research: Space Physics   125 ( 9 )   2020.9

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    DOI： 10.1029/2019JA027721

  • First global-scale synoptic imaging of a solar eclipse in the thermosphere Reviewed International journal

    Aryal, S., J. S. Evans, J. Correira, T. Dang, J. Lei, Huixin Liu, G. Jee, A. G. Burns, W. Wang, S. C. Solomon, F. I. Laskar, W. E. McClintock, R. W. Eastes

    J. Geophys. Res.   47   2020.6

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    DOI： 10.1029/2020JA027789

  • Dipolar elementary current systems for ionospheric current reconstruction at low and middle latitudes Reviewed International journal

    Vanhamaki, H., A. Maute, P. Alken, @Huixin Liu

    Earth, Planets and Space   72   2020.6

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    DOI： https://doi.org/10.1186/s40623-020-01284-1

  • Gravity wave weakening during the 2019 Antarctic stratospheric sudden warming Reviewed International journal

    Kogure, M., Yue J., @Huixin Liu

    Geophys. Res. Lett.   48   2020.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2021GL092537

  • Ionospheric F-layer scintillation weakening as observed by COSMIC/FORMOSAT-3 during the major sudden stratospheric warming in January 2013 Reviewed International journal

    Yu, T. H. Ye, Huixin Liu, C. Xia, X. Zuo, X. Yan, N. Yang, Y. Sun, B. Zhao,

    J. Geophys. Res.   2020.6

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    DOI： https://doi.org/10.1029/2019JA027721

    Other Link： https://doi.org/10.1029/2019JA027721

  • Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2-doubling Reviewed International journal

    Huixin Liu, C. Tao, H. Jin, Y. Nakamoto

    Geophys. Res. Lett.   47   2020.5

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    DOI： 10.1029/2020GL087413

  • Circulation and Tides in a Cooler Upper Atmosphere: Dynamical Effects of CO 2 Doubling Reviewed

    Huixin Liu, Chihiro Tao, Hidekatsu Jin, Yusuke Nakamoto

    Geophysical Research Letters   47 ( 10 )   2020.5

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    Thermosphere cooling is a known effect of increasing CO2 in the atmosphere. In this study, we explore the changes of thermosphere circulation and tides in the cooled thermosphere via a doubled CO2 numerical experiment using the Ground-to-topside Atmosphere Ionosphere model for Aeronomy (GAIA). The results reveal three major features. (1) The thermosphere cools about 10 K more around solstices than equinoxes, more at the summer pole than the winter pole. (2) The meridional circulation shifts downward and strongly accelerates by 5-15 m s(-1). (3) The tidal activity experiences dramatic changes, with a 40-60% reduction in the semidiurnal tides (SW2) throughout the thermosphere but an 30-50% enhancement in diurnal tides (DW1) below 200 km altitude. The nonmigrating tide DE3 has only minor changes. These changes in temperature, meridional circulation, and tides are persistent features in all seasons and can profoundly affect the spatial distribution and diurnal cycles of the ionospheric responses to CO2 doubling via atmosphere composition and electrodynamics.

    DOI： 10.1029/2020GL087413

  • Interhemispheric transport of the ionospheric F region plasma during the 2009 sudden stratosphere warming Reviewed International journal

    Zhang, R., L. Liu, Huixin Liu

    Geophys. Res. Lett.   47   2020.3

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    DOI： 10.1029/2020GL087078

  • Sunspot observations by Hisako Koyama: 1945–1996 Reviewed

    Hisashi Hayakawa, Frédéric Clette, Toshihiro Horaguchi, Tomoya Iju, Delores J Knipp, Huixin Liu, Takashi Nakajima

    492 ( 3 )   4513 - 4527   2020.3

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    Sunspot observations by Hisako Koyama: 1945–1996

  • Interhemispheric Transport of the Ionospheric F Region Plasma During the 2009 Sudden Stratosphere Warming Reviewed

    Ruilong Zhang, Libo Liu, Huixin Liu, Huijun Le, Yiding Chen, Hui Zhang

    Geophysical Research Letters   47 ( 6 )   2020.3

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    DOI： 10.1029/2020GL087078

  • Sunspot observations by Hisako Koyama: 1945-1996 Reviewed International journal

    Hayakawa, H., F. Clette, T. Horaguchi, T. Iju, D. Knipp, Huixin Liu, T. Nakajima

    Monthly Notice of Royal Astronomical Society   47   2020.2

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    DOI： doi:10.1093/mnras/stz3345

  • Niño–Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007–2015 FORMOSAT-3/COSMIC observations Reviewed International journal

    Yang Yi Sun, Huixin Liu, Yasunobu Miyoshi, Loren C. Chang, Libo Liu

    earth, planets and space   71 ( 1 )   2019.12

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    DOI： 10.1186/s40623-019-1009-7

  • Thermospheric Density Cells at High Latitudes as Observed by GOCE Satellite Preliminary Results Reviewed International journal

    Libin Weng, Jiuhou Lei, Huixin Liu, Xiankang Dou, Hanxian Fang

    Geophysical Research Letters   46 ( 21 )   11615 - 11621   2019.11

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    DOI： 10.1029/2019GL084951

  • Plasma Blobs Concurrently Observed With Bubbles in the Asian‐Oceanian Sector During Solar Maximum Reviewed

    Zheng Wang, Huixin Liu, Jiankui Shi, Guojun Wang, Xiao Wang

    Journal of Geophysical Research: Space Physics   124 ( 8 )   7062 - 7071   2019.8

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    With simultaneous ionospheric measurements from ROCSAT-1 satellite and ground ionosondes/GPS receivers, three cases of concurrent plasma blobs and bubbles in the same magnetic meridian were observed around 22:30 LT in Asian-Oceanian sector during solar maximum. Two cases were observed: equatorial spread F (ESF) over Vanimo station (geog. 2.7 degrees S, 141.3 degrees E; geom. 11.2 degrees S, 146.2 degrees W) and plasma blobs around 8.0 degrees S (geom.) on 1 June and 6 October 2003. The other case observed equatorial spread F over Hainan station (geog. 19.5 degrees N, 109.1 degrees E; geom. 9.1 degrees N, 179.1 degrees W) and plasma blob near the dip equator on 8 March 2004. Plasma blobs were all observed near 600-km height near the equator. Equatorial spread F and amplitude scintillations from the ground stations were observed near the same magnetic meridian, indicating the existence of bubbles. Considering that both plasma bubbles and blobs are field-aligned elongated structures, magnetic field line mapping shows that in the two cases at Vanimo, blobs were above bubbles, providing direct observational evidence for blob formation in the intermediate stage of plasma bubble evolution; in the case at Hainan, the blob and bubble were likely at similar height, and it could be generated by gravity wave.

    DOI： 10.1029/2018JA026373

  • Seeding of Equatorial Plasma Bubbles by Vertical Neutral Wind Reviewed International journal

    Tatsuhiro Yokoyama, Hidekatsu Jin, Hiroyuki Shinagawa, Huixin Liu

    Geophysical Research Letters   46 ( 13 )   7088 - 7095   2019.7

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    DOI： 10.1029/2019GL083629

  • Seeding of Equatorial Plasma Bubbles by Vertical Neutral Wind Reviewed

    Tatsuhiro Yokoyama, Hidekatsu Jin, Hiroyuki Shinagawa, Huixin Liu

    Geophysical Research Letters   46 ( 13 )   7088 - 7095   2019.7

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    The seeding mechanism of equatorial plasma bubbles (EPBs) in the ionosphere has not been fully understood for several decades. Before investigating the complex seeding process by atmospheric gravity waves, which have been considered as a possible candidate, we investigate the vertical neutral wind effect on the EPB seeding by making the numerical simulation setup as simple as possible. It is presented that the vertical wind over the dip equator with an amplitude of as low as 5 m/s can seed EPBs effectively. The upward wind reduces the eastward current and produces the eastward polarization electric field, so that the bottomside F region pushed by the upward wind is going to form upwellings and penetrate into the topside F region accelerated by the Rayleigh-Taylor instability. It is suggested that the vertical wind perturbations driven by gravity waves should play an important role in seeding EPBs.

    DOI： 10.1029/2019GL083629

  • Global sounding of F region irregularities by COSMIC during a geomagnetic storm Reviewed International journal

    Klemens Hocke, Huixin Liu, Nicholas Pedatella, Guanyi Ma

    Annales Geophysicae   37 ( 2 )   235 - 242   2019.4

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    DOI： 10.5194/angeo-37-235-2019

  • Global sounding of F region irregularities by COSMIC during a geomagnetic storm Reviewed

    Klemens Hocke, Huixin Liu, Nicholas Pedatella, Guanyi Ma

    Annales Geophysicae   37 ( 2 )   235 - 242   2019.4

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    Language：Others   Publishing type：Research paper (scientific journal)  

    DOI： 10.5194/angeo-37-235-2019

  • El Nino-Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007-2015 FORMOSAT- 3/COSMIC observations (vol 71, 35, 2019) Reviewed

    Sun Yang-Yi, Liu Huixin, Miyoshi Yasunobu, Chang Loren C, Liu Libo

    EARTH PLANETS AND SPACE   71   2019.4

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    El Nino-Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007-2015 FORMOSAT- 3/COSMIC observations (vol 71, 35, 2019)

    DOI： 10.1186/s40623-019-1025-7

  • Observations of low-latitude travelling ionospheric disturbances by a 630.0-nm airglow imager and the CHAMP satellite over Indonesia Reviewed International journal

    A. C. Moral, K. Shiokawa, S. Suzuki, Huixin Liu, Y. Otsuka, C. Y. Yatini

    J. Geophys. Res.   63 ( 8 )   2623 - 2637   2019.3

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    DOI： https://doi.org/10.1029/2018JA025634

  • Nino-Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007-2015 FORMOSAT-3/COSMIC observations Reviewed

    Sun Yang-Yi, Liu Huixin, Miyoshi Yasunobu, Chang Loren C, Liu Libo

    EARTH PLANETS AND SPACE   71   2019.3

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    Nino-Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007-2015 FORMOSAT-3/COSMIC observations

    DOI： 10.1186/s40623-019-1009-7

  • Vertical Structure of Terdiurnal Tides in the Antarctic MLT Region 15-Year Observation Over Syowa (69°S, 39°E) Reviewed

    Huixin Liu, Masaki Tsutsumi, Hanli Liu

    Geophysical Research Letters   46 ( 5 )   2364 - 2371   2019.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2019GL082155

  • 小山ひさ子氏: アマチュア天文家から 世界的な太陽観測者へ の道程 Reviewed

    Huixin Liu, H. Hayakawa, J. Isa

    天文月報   112 ( 3 )   193 - 198   2019.3

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  • Vertical structure of terdiurnal tides in the Antarctic MLT region: 15-year observation over Syowa (69S, 39E) Reviewed International journal

    Huixin Liu, M. Tsutsumi, Hanli Liu

    Geophys. Res. Lett.   46   2019.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2018JA025634

  • Precursor effect of March 11 2011 off the coast of Tohoku earthquake on high and low latitude ionospheres and its possible disturbing mechanism Reviewed International journal

    K. Oyama, C. H. Chen, L. Bankov, D. Minakshi, K. Ryu, J.Y. Liu, Huixin Liu

    Advances in Space Research   63   2019.1

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    DOI： https://doi.org/10.1016/j.asr.2018.12.042

  • Plasma Blobs Concurrently Observed With Bubbles in the Asian-Oceanian Sector During Solar Maximum Reviewed International journal

    Zheng Wang, Huixin Liu, Jiankui Shi, Guojun Wang, Xiao Wang

    Journal of Geophysical Research: Space Physics   2019.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2018JA026373

  • El Niño–Southern Oscillation effect on quasi-biennial oscillations of temperature diurnal tides in the mesosphere and lower thermosphere Reviewed International journal

    Yang Yi Sun, Huixin Liu, Yasunobu Miyoshi, Libo Liu, Loren C. Chang

    Earth, Planets and Space   70 ( 1 )   2018.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1186/s40623-018-0832-6

  • Akatsuki at Venus: the first year of scientific operation Reviewed International journal

    M. Nakamura, D. Titov, K. McGouldrick, P. Drossart, J.L. Bertaux, Huixin Liu

    Earth, Planets and Space   70   2018.7

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    DOI： https://doi.org/10.1186/s40623-018-0916-3

  • Generation of Electron Acoustic Waves in the Topside Ionosphere From Coupling With Kinetic Alfven Waves A New Electron Energization Mechanism Reviewed International journal

    Run Shi, Binbin Ni, Danny Summers, Huixin Liu, Akimasa Yoshikawa, Beichen Zhang

    Geophysical Research Letters   45 ( 11 )   5299 - 5304   2018.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2018GL077898

  • Interannual Variability of the Daytime Equatorial Ionospheric Electric Field Reviewed International journal

    Y. Yamazaki, C. Stolle, J. Matzka, Huixin Liu, C. Tao

    Journal of Geophysical Research: Space Physics   123   2018.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2017JA025165

  • Do minor sudden stratospheric warmings in the Southern Hemisphere (SH) impact coupling between stratosphere and mesosphere-lower thermosphere (MLT) like major warmings? 3. Space science Reviewed

    S. Eswaraiah, Yong Ha Kim, Huixin Liu, M. Venkat Ratnam, Jaewook Lee

    Earth, Planets and Space   69 ( 1 )   2017.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1186/s40623-017-0704-5

  • Ms. Hisako Koyama:From Amateur Astronomer to Long-Term Solar Observer Reviewed International journal

    Delores Knipp, Huixin Liu, Hisashi Hayakawa

    Space Weather   15 ( 10 )   1215 - 1221   2017.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2017SW001704

  • Equinoctial asymmetry in the zonal distribution of scintillation as observed by GPS receivers in Indonesia Reviewed

    P. Abadi, Y. Otsuka, K. Shiokawa, A. Husin, Huixin Liu, S. Saito

    Journal of Geophysical Research   122 ( 8 )   8947 - 8958   2017.8

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2017JA024146

  • Medium-scale gravity wave activity in the bottomside F region in tropical regions Reviewed International journal

    Huixin Liu, Nicholas Pedatella, Klemens Hocke

    Geophysical Research Letters   44 ( 14 )   7099 - 7105   2017.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2017GL073855

  • The non–storm time corrugated upper thermosphere What is beyond MSIS? Invited Reviewed International journal

    Huixin Liu, Jeff Thayer, Yongliang Zhang, Woo Kyoung Lee

    Space Weather   15 ( 6 )   746 - 760   2017.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2017SW001618

  • Peak time of equatorial electrojet from different longitude sectors during fall solar minimum Reviewed

    N. S.A. Hamid, Huixin Liu, T. Uozumi, Akimasa Yoshikawa, N. M.N. Annadurai

    Journal of Physics: Conference Series   852 ( 1 )   2017.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1088/1742-6596/852/1/012015

  • ENSO effects on MLT diurnal tides: A 21 year reanalysis data-driven GAIA model simulation Reviewed International journal

    Liu Huixin, Y. Sun, Yasunobu Miyoshi, H. Jin

    J. Geophys. Res   122   2017.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2017JA024011

  • Mesospheric temperatures estimated from the meteor radar observations at Mohe, China Reviewed International journal

    L. Liu, Liu Huixin, H. Le, Y. Chen, Y. Sun, B. Ning, L. Hu, W. Wan, N. Li, J. Xiong

    J. Geophys. Res   122   2017.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2016JA023776

  • Quasi-biennial oscillation of the ionospheric wind dynamo Reviewed International journal

    Y. Yamazaki, Liu Huixin, Y. Sun, Yasunobu Miyoshi, M. Kosch, M. Mlynczak

    J. Geophys. Res   122   2017.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2016JA023684

  • Variations of the meteor echo heights at Beijing and Mohe Reviewed International journal

    L. Liu, Liu Huixin, Y. Chen, H. Le, Y. Sun, B. Ning, L. Hu, W. Wan

    J. Geophys. Res   122   2017.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/ 2016JA023448

  • Prolonged multiple excitation of large-scale traveling atmospheric disturbances (TADs) by successive and interacting coronal mass ejections Reviewed International journal

    J. Guo, F. Wei, X. Feng, J. Forbes, Y. Wang, Liu Huixin, W. Wan

    J. Geophys. Res   2016.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2015JA022076

  • Thermospheric wind observed by GOCE: wind jets and seasonal variations Reviewed International journal

    Liu Huixin, E. Doornbos, J. Nakashima

    J. Geophys. Res   121   2016.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2016JA022938

  • Alfvén waves as a solar-interplanetary driver of the thermospheric disturbances Reviewed International journal

    Jianpeng Guo, F. Wei, Xueshang Feng, Liu Huixin, Weixing Wan, et. al

    Scientific Reports   2016.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1038/srep-18895

  • Modifications of the ionosphere prior to large earthquakes: report from the ionosphere precursor study group Reviewed International journal

    K. Oyama, M. Devi, K. Ryu, C. Chen, J. Liu, Liu Huixin, L. Bankov

    Geoscience Letter   2016.5

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    DOI： doi:10.1186/s40562-016-0038-3

  • Precursory enhancement of EIA in the morning sector: contribution from Mid-latitude large earthquake in the north-east Asian region Reviewed International journal

    K. Ryu, K. Oyama, L. Bankov, C. Chen, M. Devi, Liu Huixin, J. Liu

    Adv. in Space. Res   2016.5

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    DOI： http://dx.doi.org/10.1016/j.asr.2015.08.030

  • Thermospheric inter-annual variability and its potential connection to ENSO and stratospheric QBO Reviewed International journal

    Liu Huixin

    Earth. Planets and Space   2016.4

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    DOI： 10.1186/s40623-016-0455-8

  • Observations of a large-scale gravity wave propagating over an extremely large horizontal distance in the thermosphere Reviewed International journal

    Jianpeng Guo, J. Forbes, F. Wei, Xueshang Feng, Liu Huixin, Weixing Wan, et. al

    Geophys. Res. Lett.   42   2015.8

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2015GL065671

  • Empirical model of equatorial electrojet based on ground-based magnetometer data during solar minimum in fall Reviewed International journal

    Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto

    Earth. Planets and Space   67   2015.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1186/s40623-015-0373-1

  • Longitudinal and Solar Activity Dependence of Equatorial Electrojet At Southeast Asian Sector Reviewed International journal

    Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto

    IEEE   262 - 266   2015.6

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  • Structure and origins of the Weddell Sea Anomaly from tidal and planetary wave signatures in FORMOSAT-3/COSMIC observations and GAIA GCM simulations Reviewed International journal

    L. Chang, Liu Huixin, Yasunobu Miyoshi, C. Chen, F. Chang, C. Lin, J. Y. Liu, Y. Y. Sun

    J. Geophys. Res.   120   1325 - 1340   2015.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： doi:10.1002/2014JA020752

  • Ionospheric response to 2009 Sudden Stratospheric Warming in the northern hemisphere Reviewed International journal

    K.-I. Oyama, J. T. Jhou, J. T. Lin, C. Lin, Liu Huixin, Kiyohumi Yumoto

    J. Geophys. Res.   119   1 - 16   2014.11

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014JA020014

  • Relationship between equatorial electrojet and global Sq currents at dip equator region Reviewed International journal

    Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto

    Earth, Planets and Space   66   1 - 11   2014.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： http://www.earth-planets-space.com/content/66/1/146

  • Ionospheric shock waves triggered by rockets Reviewed International journal

    C. Lin, J. T. Lin, C.H. Chen, J. Y. Liu, Y. Y. Sun, Y. Kakinam, M. Matsumura, Liu Huixin, R. J. Rau

    Ann. Geophys.   32   1145 - 1152   2014.9

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.5194/angeo-32-1145-2014

  • Constructive interference of large-scale gravity waves excited by interplanetary shock on 29 October 2003: CHAMP observation Reviewed International journal

    Jianpeng Guo, Liu Huixin, Xueshang Feng, Weixing Wan, Yue Deng, Chaoxu Liu

    J. Geophys. Res.   119   1 - 6   2014.8

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014JA020255

  • Capacity building: A tool for advancing space weather science Reviewed International journal

    M. G. 4. Cardinal, Yoshikawa Akimasa, Huixin Liu, Masakazu Watanabe, Kiyohumi Yumoto, Hideaki Kawano

    Space Weather   12   2014.8

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014SW001110

  • Thermal and dynamical changes of the zonal mean state of the thermosphere during the 2009 SSW: GAIA simulations Reviewed International journal

    Liu Huixin, Yasunobu Miyoshi, Saburo Miyahara, H. Jin, H. Fujiwara, H. Shinagawa

    J. Geophys. Res.   119   1 - 7   2014.8

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014JA020222

  • MLT and seasonal dependence of auroral electrojets: IMAGE magnetometer network observations Reviewed International journal

    Jianpeng Guo, Liu Huixin, Xueshang Feng, T. I. Pulkkinen, E. I. Tanskanen, Chaoxu Liu, Dingkun Zhong, Yuan Wang

    J. Geophys. Res.   119   ? - ?   2014.4

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014JA019843

  • Annual variations in westward auroral electrojet and substorm occurrence rate during solar cycle 23 Reviewed International journal

    Jianpeng Guo, T. I. Pulkkinen, E. I. Tanskanen, Xueshang Feng, Barbara A. Emery, Liu Huixin, Chaoxu Liu, Dingkun Zhong

    J. Geophys. Res.   119   ? - ?   2014.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2013JA019742

  • CHAMP observations of the low latitude ionosphere and thermosphere and comparisons to physical models Invited Reviewed International journal

    Claudia Stolle, Huixin Liu

    AGU monograph: Modeling the Ionosphere-Thermosphere   201   ? - ?   2014.2

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  • Equatorial  electrojet  dependence  on  solar  activity in  the  Southeast  Asia  sector Reviewed International journal

    Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto

    Antarctic Record   57 ( 3 )   329 - 337   2013.12

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    Language：English   Publishing type：Research paper (scientific journal)  

  • Storm-time atmospheric density modeling using neural networks and its application in orbit propagation Reviewed International journal

    Hongru Chen, Liu Huixin, Toshiya Hanada

    Adv. in Space Research   53   558 - 567   2013.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.asr.2013.11.052

  • Brief Study of Equatorial Electrojet and Global Sq Currents At Southeast Asia Region Reviewed International journal

    Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto

    IEEE International Conference on Space Science and Communication (IconSpace), 1-3 July 2013   194 - 197   2013.7

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    Language：English   Publishing type：Research paper (international conference proceedings)  

  • Upper atmosphere response to stratosphere sudden warming: Local time and height dependence simulated by GAIA model Reviewed International journal

    Huixin Liu, H. Jin, Yasunobu Miyoshi, H. Fujiwara, H. Shinagawa

    Geophys. Res. Lett.   40   635 - 640   2013.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/grl.50146

  • Coupling of electrons and inertial Alfven waves in the topside ionosphere Reviewed International journal

    R. Shi, Huixin Liu, Akimasa Yoshikawa, Beichen Zhang, Binbin Ni

    J. Geophys. Res.   118   843 - 848   2013.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： doi:10.1002/jgra.50355

  • Empirical model of the thermospheric mass density based on CHAMP satellite observations Reviewed International journal

    Huixin Liu, T. Hirano, S. Watanabe

    J. Geophys. Res.   118   843 - 848   2013.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： doi:10.1002/jgra.50144

  • Sq current system during stratospheric sudden warming events in 2006 and 2009 Reviewed International journal

    Y. Yamazaki, A. D. Richmond, Liu Huixin, Kiyohumi Yumoto, Y. Tanaka

    J. Geophys. Res.   117   2012.12

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    DOI： 10.1029/2012JA018116

  • Electromagnetic Coupling on Solar-Terrestrial System: Possible effects on seismic activities Reviewed International journal

    Jusoh M. H., Kiyohumi Yumoto, Abdul Hamid N. S., Huixin Liu

    Proceedings of ISAP2012   1160 - 1163   2012.11

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  • First observational evidence for opposite zonal electric fields in equatorial E and F region altitudes during a geomagnetic storm period Reviewed International journal

    S. Tulasi Ram, N. Balan, B. Veenadhari, S. Gurubaran, S. Ravindran, T. Tsugawa, Liu Huixin, K. Niranjan, T. Nagatsuma

    J. Geophys. Res.   118   2012.9

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2012JA018045

  • Numerical simulation of the equatorial wind jet in the thermosphere Reviewed International journal

    Y. Miyoshi, H. Fujiwara, H. Jin, H. Shinagawa, Huixin Liu

    J. Geophys. Res.   117   2012.3

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    DOI： 10.1029/2011JA017373

  • Wave-4 structure of the neutral density in the thermosphere and its relation to atmospheric tides Reviewed International journal

    Yasunobu Miyoshi, H. Jin, H. Fujiwara, H. Shinagawa, Huixin Liu

    J. Atmos. Solar-Terres. Phys.,   90   45 - 51   2012.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.jastp.2011.12.002

  • New Aspects of the Coupling Between Thermosphere and Ionosphere, with Special regards to CHAMP Mission Results Invited Reviewed International journal

    Lühr, H., Huixin Liu, J. Park, S. Muller,

    IAGA Special Sopron Book Series   2011.10

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    Language：English  

    DOI： 10.1007/978-94-007-0326-1_22

  • Equatorial Electrodynamics and Neutral Background in the Asian Sector During the 2009 Stratospheric Sudden Warming Reviewed International journal

    Liu Huixin, M. Yamamoto, E. Doornbos

    J. Geophys. Res.   116   2011.8

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2011JA016607

  • New aspects of thermospheric and ionospheric storms revealed by CHAMP Reviewed International journal

    N. Balan, M. Yamamoto, J. Y. Liu, Y. Otsuka, Huixin Liu, and H. Lühr

    J. Geophys. Res.   116   2011.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2010JA016399

  • In-situ CHAMP observations of the ionosphere-thermosphere coupling Reviewed International journal

    Lühr, H. J. Park, P. Ritter, Huixin Liu

    Space Sci. Rev.   2011.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1007/s11214-011-9798-4

  • Strong thermosphere cooling during the 2009 major statratosphere warming Reviewed International journal

    Huixin Liu, E. Doornbos, M. Yamamoto, S. T. Ram

    Geophys. Res. Lett   38   2011.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2011GL047898

  • Comment on “Westward electric field penetration to the dayside equatorial ionosphere during the main phase of the geomagnetic storm on 22 July 2009” by V. Sreeja et al. Reviewed International journal

    S. Tulasi Ram, M. Yamamoto, Huixin Liu, B. Veenadhari, S. Alex

    J. Geophys. Res.   116   2011.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2010JA016634

  • Weakening of the mid-latitude summer night anomaly during geomagnetic storms Reviewed International journal

    Huixin Liu, M. Yamamoto

    Earth. Planets and Space   63   2011.6

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  • Comparison of FORMOSAT‐3/COSMIC radio occultation measurements with radio tomography Reviewed International journal

    S. V. Thampi, M. Yamamoto, C. Lin, Huixin Liu

    Radio Science   46   2011.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2010RS004431

  • On the formation of a fast thermospheric zonal wind at the magnetic dip equator Reviewed International journal

    T. Kondo, A. D. Richmond, Huixin Liu, J. Lei, S. Watanabe

    Geophys. Res. Lett.   38   2011.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2011GL047255

  • Model study on the formation of the equatorial mass density anomaly in the thermosphere Reviewed International journal

    Y. Miyoshi, H. Fujiwara, H. Jin, H. Shinagawa, Huixin Liu, and K. Terada

    J. Geophys. Res.   116   2011.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2010JA016315

  • Solar flux variation of the electron temperature morning overshoot in the equatorial F region Reviewed International journal

    C. Stolle, Huixin Liu, V. Truhlík, H. Lühr, P. G. Richards

    J. Geophys. Res.   116   2011.4

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2010JA016235

  • Mid-latitude summer nighttime anomaly (MSNA) – observations and model simulations Reviewed International journal

    Thampi, S. V., N. Balan, C. Lin, Liu Huixin, M. Yamamoto

    Ann. Geophys.,   29 ( 157 )   165   2011.4

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  • Midnight latitude-altitude distribution of 630-nm airglow in the Asian sector measured with Formosat-2/ISUAL Reviewed International journal

    Adachi, T., M. Yamaoka, M. Yamamoto, Y. Otsuka, Liu Huixin, C. Hsiao, A. Chen, R. Hsu

    J. Geophys. Res   115   2010.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2009JA015147

  • Nighttime-like Quasi Periodic echoes induced by a partial solar eclipse Reviewed International journal

    Thampi, S. V., M. Yamamoto, Liu Huixin, S. Saito, Y. Otsuka, A. K. Patra

    Geophys. Res. Lett.   37   2010.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2010GL042855

  • Phase reversal of the diurnal cycle in the mid-latitude ionosphere Reviewed International journal

    Liu Huixin, Thampi, S. V., M. Yamamoto

    J. Geophys. Res   115   2010.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2009JA014689

  • First Tomographic Observations of the Mid-latitude Summer Nighttime Anomaly (MSNA) over Japan Reviewed International journal

    Thampi, S. V., C. Lin, Liu Huixin, M. Yamamoto

    J. Geophys. Res.   114   2009.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2009JA014439

  • Wave-4 pattern of the equatorial mass density anomaly- A thermospheric signature of tropical deep convection Reviewed International journal

    Liu Huixin, M. Yamamoto, H. Luehr

    Geophys. Res. Lett.   36   2009.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2009GL039865

  • A solar terminator wave in thermospheric wind and density simultaneously observed by CHAMP Reviewed International journal

    Liu Huixin, H. Luehr, S. Watanabe

    Geophys. Res. Lett.   36   2009.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2009GL038165

  • Fast thermospheric wind jet at the Earth's dip equator Reviewed International journal

    Liu Huixin, S. Watanabe, T. Kondo

    Geophys. Res. Lett.   36   2009.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2009GL037377

  • Seasonal variation in the longitudinal structure of the equatorial ionosphere: does it reflect tidal influences from below? Reviewed International journal

    Liu Huixin, S. Watanabe

    J. Geophys. Res.   113   2008.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2008JA013027

  • Contrasting behavior of the thermosphere and ionosphere to the Oct. 28, 2003 solar flare Reviewed International journal

    Liu Huixin, H. Luehr, S. Watanabe, W. Koehler, M. Manoj

    J. Geophys. Res.   112   2007.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2007JA012313

  • Zonal winds in the equatorial upper thermosphere: Decomposing the solar flux, geomagnetic activity, and seasonal dependencies Reviewed International journal

    Liu Huixin, H. Luehr, S. Watanabe, V. Henize, W. Koehler, P. Visser

    J. Geophys. Res.   111   2007.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2005JA011415

  • Solar activity dependence of the electron density at 400 km at equatorial and low latitudes observed by CHAMP Reviewed International journal

    Liu Huixin, C. Claudia, M. Forster, S. Watanabe

    J. Geophys. Res.   112   2007.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2007JA012616

  • Evaluation of the IRI Model Using CHAMP Observations in Polar and Equatorial Regions Reviewed International journal

    Liu Huixin, C. Claudia, S. Watanabe, T. Abe, D. Cooke

    Adv. in Space. Res.,   39   904 - 909   2007.3

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  • Climatology of the Equatorial Thermospheric Mass Density Anomaly Reviewed International journal

    Liu Huixin, H. Luehr, S. Watanabe

    J. Geophys. Res.   112   2007.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2006JA012199

  • Strong disturbance of the upper thermospheric density due to magnetic storms: CHAMP observations Reviewed International journal

    Liu Huixin, H. Luehr

    J. Geophys. Res.   110   2005.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2004JA010908

  • Global distribution of the thermospheric total mass density derived from CHAMP Reviewed International journal

    Liu Huixin, H. Luehr, V. Henize, W. Koehler

    J. Geophys. Res.   110   2005.5

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2004JA010741

  • Velocity shear-related ion upflows in the low-altitude ionosphere Reviewed International journal

    Liu Huixin, G. Lu

    Ann. Geophysics.   22   1149 - 1153   2004.10

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  • Diurnal, seasonal, and geomagnetic variations of large field-aligned ion upflows in the high-latitude ionospheric F region Reviewed International journal

    Liu Huixin, S. Y. Ma, K. Schlegel

    J. Geophys. Res   106   24,651 - 24,662   2001.6

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  • Combined ESR and EISCAT observations of the dayside polar cap and auroral oval during the May 15, 1997 storm Reviewed International journal

    Liu Huixin, K. Schlegel, S. Y. Ma

    Ann. Geophysics.   18   1067 - 1072   2000.10

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  • Enhanced Sporadic E Layer and Its Perturbations During the 2022 Hunga Volcanic Eruption Reviewed

    Lihui Qiu, Huixin Liu, Yifan Qi, Facundo L. Poblet

    Space Weather   22 ( 7 )   2024.7   （ ISSN:1542-7390 eISSN:1542-7390 ）

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    Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    Abstract

    Sporadic E (Es) layers are plasma irregularities significantly affecting radio communication and navigation systems. And, their dominant formation mechanism at mid‐latitudes, known as the wind shear theory, suggests that they serve as indicators of the atmosphere‐ionosphere coupling processes in the mesosphere and lower thermosphere region. On 15 January 2022, the Hunga Tonga‐Hunga Ha'api submarine volcanic eruption provided a unique opportunity to investigate the Es layer responses to lower atmospheric perturbations. Using the FORMOSAT‐7/COSMIC‐2 radio occultation and ground‐based ionosonde observations, this study reveals the spatial‐temporal behaviors of the Es layers after the Hunga volcanic eruption. The results show that significant Es layer perturbations occurred over the northwest of the epicenter ∼4 hr after the eruption and lasted for approximately ∼22 hr. We also calculated the geographical distribution of the vertical ion convergence (VIC) using neutral winds obtained from the Michelson Interferometer for Global High‐resolution Thermospheric Imaging on the Ionospheric Connection Explorer (ICON) satellite. A comparison of the geographical distribution of positive VIC and Es layer perturbations shows a good agreement, which indicates that the enhanced Es layers are caused by strong VIC associated with the atmospheric perturbations due to the eruption. This study presents observational evidence for coupling between the Es layer and lower atmospheric perturbations, which can be helpful for understanding the occasionality and variability of Es layer occurrence.

    DOI： 10.1029/2023SW003837

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  • Third‐Order Structure Functions of Zonal Winds in the Thermosphere Using CHAMP and GOCE Observations Reviewed

    Facundo L. Poblet, Huixin Liu, Jorge L. Chau

    Geophysical Research Letters   51 ( 11 )   2024.6   （ ISSN:0094-8276 eISSN:1944-8007 ）

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    Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    Abstract

    We use multi‐year observations of cross‐track winds (u) from the CHAllenging Minisatellite Payload (CHAMP) and the Gravity Field and Steady State Ocean Circulation Explorer (GOCE) to calculate third‐order structure functions in the thermosphere as a function of horizontal separation (s). They are computed using the mean (〈δu<sup>3</sup>〉) and the median and implemented over non‐polar satellite paths in both hemispheres. On height averages, 〈δu<sup>3</sup>〉 is shown to scale with s<sup>2</sup> for s ≃ 80–1,000 km, in agreement with equivalent estimates in the lower atmosphere from aircraft observations. Conversely, follows an s<sup>3</sup> power law for almost the whole s range, consistent with the two‐dimensional turbulence scaling law for a direct enstrophy cascade. These scaling laws appear independent of winds in distinct atmospheric regions. Furthermore, the functions are predominantly positive, indicating a preferential cyclonic motion for the wind.

    DOI： 10.1029/2024GL108367

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  • <i>In Memoriam</i> of Editor Jennifer L. Gannon

    Lugaz, N; Knipp, D; Morley, SK; Liu, HX; Hapgood, M; Carter, B; Zou, SS; Lei, JH; Welling, D

    SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS   22 ( 6 )   2024.6   （ eISSN:1542-7390 ）

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  • Evaluation of the Empirical Scaling Factor of Joule Heating Rates in TIE‐GCM With EISCAT Measurements Reviewed

    Florian Günzkofer, Huixin Liu, Gunter Stober, Dimitry Pokhotelov, Claudia Borries

    Earth and Space Science   11 ( 4 )   2024.4   （ eISSN:2333-5084 ）

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    Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Earth and Space Science  

    Joule heating is one of the main energy inputs into the thermosphere-ionosphere system. Precise modeling of this process is essential for any space weather application. Existing thermosphere-ionosphere models tend to underestimate the actual Joule heating rate quite significantly. The Thermosphere-Ionosphere-Electrodynamics General-Circulation-Model applies an empirical scaling factor of 1.5 for compensation. We calculate vertical profiles of Joule heating rates from approximately 2,220 hr of measurements with the EISCAT incoherent scatter radar and the corresponding model runs. We investigate model runs with the plasma convection driven by both the Heelis and the Weimer model. The required scaling of the Joule heating profiles is determined with respect to the Kp index, the Kan-Lee merging electric field EKL, and the magnetic local time. Though the default scaling factor of 1.5 appears to be adequate on average, we find that the required scaling varies strongly with all three parameters ranging from 0.46 to ∼20 at geomagnetically disturbed and quiet times, respectively. Furthermore, the required scaling is significantly different in runs driven by the Heelis and Weimer model. Adjusting the scaling factor with respect to the Kp index, EKL, the magnetic local time, and the choice of convection model would reduce the difference between Joule heating rates calculated from measurement and model plasma parameters.

    DOI： 10.1029/2023EA003447

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  • Thank You to Our Peer Reviewers in 2023

    Noe Lugaz, Brett Carter, Jennifer L. Gannon, Huixin Liu, Steve K. Morley, Shasha Zou

    Space Weather   22 ( 4 )   2024.4   （ eISSN:1542-7390 ）

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    DOI： 10.1029/2024SW003929

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  • A machine learning approach for estimating the drift velocities of equatorial plasma bubbles based on All-Sky Imager and GNSS observations

    Githio L., Liu H., Arafa A.A., Mahrous A.

    Advances in Space Research   2024   （ ISSN:02731177 ）

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    Equatorial Plasma Bubbles (EPBs) are zones characterized by fluctuations in plasma densities which form in the low-latitude ionosphere primarily during the post-sunset. They subject radio signals to amplitude and phase variabilities, affecting the functioning of technological systems that utilize the Global Navigation Satellite Systems (GNSS) signals for navigation. Thus, understanding EPB occurrence patterns and morphological features is vital for mitigating their effects. In this work, we employed two GNSS receivers and an All-Sky Imager (ASI) to conduct simultaneous observations on the morphology of EPBs over Brazil. The main objectives of the study were (1) to develop a Random Forest (RF) machine-learning model to estimate and predict the zonal drift velocities of EPBs, and (2) to compare the model predictions with actual EPB drifts inferred from the two instruments, as well as zonal neutral wind speeds obtained from the Horizontal Wind Model (HWM-14). In the model development, we utilized reliable EPB drift measurements made during geomagnetically quiet days between 2013 and 2017 in Brazil. The model predicted the velocities based on parameters including the day of the year, universal time, critical frequency of the F2 layer (foF2), solar and interplanetary indices. The correlation coefficients of 0.98 and 0.96 and RMSE values of 10.61 m/s and 10.06 m/s were obtained upon training and validation correspondingly. We evaluated the accuracy of the model in predicting EPB drifts on two geomagnetically quiet nights where an average correlation coefficient of 0.89 and an RMSE of 15.74 m/s were obtained. The predicted drifts, the zonal neutral wind velocities, and the GNSS and ASI velocity measurements were put into context for validation purposes. Overall, the velocities were comparable and ranged between ∼100 m/s and ∼30 m/s from the hours of 00 UT to 05 UT. The results confirmed the accuracy and applicability of the model, revealing the ionosphere-thermosphere coupling influence on the nocturnal propagation of EPBs under the full activation of the F region dynamo.

    DOI： 10.1016/j.asr.2024.08.067

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  • Contribution of the lower atmosphere to the day-to-day variation of thermospheric density

    Yue, J; Yu, WD; Pedatella, N; Bruinsma, S; Wang, NC; Liu, HX

    ADVANCES IN SPACE RESEARCH   72 ( 12 )   5460 - 5475   2023.12   （ ISSN:0273-1177 eISSN:1879-1948 ）

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    In this paper we carried out a numerical experiment using the Specified Dynamics mode of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension (SD-WACCM-X). One SD-WACCM-X run was with realistic Kp and F10.7 and the other with constant Kp and F10.7. By comparing the day-to-day variability of thermosphere mass density at 300 km (low earth orbit, LEO) and 120 km (reentry level) in these two runs, we find that the density variation at 300 km is mainly driven by geomagnetic and solar forcing while at 120 km it is exclusively controlled by the lower atmosphere. At LEO altitudes, during solar minimum and geomagnetic quiet days, the impact from the lower atmosphere is much smaller than the effect of solar and geomagnetic variations but is not negligible (5–10% vs 20%).

    DOI： 10.1016/j.asr.2022.06.011

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  • Space Weather in the Popular Media, and the Opportunities the Upcoming Solar Maximum Brings Reviewed

    Brett A. Carter, Noé Lugaz, Steven K. Morley, Jennifer Gannon, Shasha Zou, Huixin Liu

    Space Weather   21 ( 12 )   2023.12   （ eISSN:1542-7390 ）

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    The media interest/coverage of space weather has been increasing as we approach solar maximum and the private space industry has grown significantly since the last significant solar maximum in 2000–2002. It is not uncommon for space weather media coverage to use hyperbole with frequent references to the infamous “Carrington event.” The implications of associating each of the many upcoming moderate-to-severe storms with the Carrington event are discussed, and we encourage the curbing of hyperbole whenever possible. While there is an excellent but small cohort of space weather researchers actively engaging with the media, we urge more (particularly early-to-mid career) to take advantage of media training resources and to join in. We also call for these efforts to be broadly supported by peers and institutions for the benefit of space weather as a discipline.

    DOI： 10.1029/2023SW003819

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  • Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes over Europe Reviewed

    Juliana Jaen, Toralf Renkwitz, Huixin Liu, Christoph Jacobi, Robin Wing, Aleš Kuchař, Masaki Tsutsumi, Njål Gulbrandsen, Jorge L. Chau

    Atmospheric Chemistry and Physics   23 ( 23 )   14871 - 14887   2023.12   （ ISSN:1680-7316 eISSN:1680-7324 ）

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    Continuous wind measurements using partial-reflection radars and specular meteor radars have been carried out for nearly 2 decades (2004-2022) at middle and high latitudes over Germany (g1/4g54ggN) and northern Norway (g1/4g69ggN), respectively. They provide crucial data for understanding the long-Term behavior of winds in the mesosphere and lower thermosphere. Our investigation focuses on the summer season, characterized by the low energy contribution from tides and relatively stable stratospheric conditions. This work presents the long-Term behavior, variability, and trends of the maximum velocity of the summer eastward, westward, and southward winds. In addition, the geomagnetic influence on the summer zonal and meridional wind is explored at middle and high latitudes. The results show a mesospheric westward summer maximum located around 75gkm with velocities of 35-54gmgs-1, while the lower-Thermospheric eastward wind maximum is observed at g1/4g97gkm with wind speeds of 25-40gmgs-1. A weaker southward wind peak is found around 86gkm, ranging from 9 to 16gmgs-1. The findings indicate significant trends at middle latitudes in the westward summer maxima with increasing winds over the past decades, while the southward winds show a decreasing trend. On the other hand, only the eastward wind in July has a decreasing trend at high latitudes. Evidence of oscillations around 2-3, 4, and 6 years modulate the maximum velocity of the summer winds. In particular, a periodicity between 10.2 and 11.3 years found in the westward component is more significant at middle latitudes than at high latitudes, possibly due to solar radiation. Furthermore, stronger geomagnetic activity at high latitudes causes an increase in eastward wind velocity, whereas the opposite effect is observed in zonal jets at middle latitudes. The meridional component appears to be disturbed during high geomagnetic activity, with a notable decrease in the northward wind strength below approximately 80gkm at both latitudes.

    DOI： 10.5194/acp-23-14871-2023

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  • Special issue "DynamicEarth: Earth's interior, surface, ocean, atmosphere, and near space interactions"

    Stolle, C; Baerenzung, J; Kronberg, EA; Kusche, J; Liu, H; Shimizu, H

    EARTH PLANETS AND SPACE   75 ( 1 )   2023.9   （ ISSN:13438832 eISSN:1880-5981 ）

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    DOI： 10.1186/s40623-023-01893-6

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  • New Space Companies Meet a “Normal” Solar Maximum Reviewed

    Noé Lugaz, Huixin Liu, Brett A. Carter, Jennifer Gannon, Shasha Zou, Steven K. Morley

    Space Weather   21 ( 9 )   2023.9   （ eISSN:1542-7390 ）

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    The monthly mean sunspot number has been larger in June–July 2023 than the double peak of solar cycle 24 (146 in February 2014 and 139 in November 2011) and brings us back to the sunspot level of solar cycle 23. However, the number of rocket launches, satellites in orbit and private space companies has increased dramatically in the past 20 years. Additionally, there is a growing interest for space exploration beyond Earth's orbit, to the Moon and beyond, which comes with higher risk of being affected by space weather. Here, we discuss some of these trends and the role of the journal to improve awareness of space weather impacts.

    DOI： 10.1029/2023SW003702

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  • Horizontal structure of convergent wind shear associated with sporadic E layers over East Asia Reviewed

    LiHui Qiu, Xian Lu, Tao Yu, Yosuke Yamazaki, HuiXin Liu, Yang-Yi Sun, HaoNan Wu, XiaoMin Zuo, XiangXiang Yan, Yan Yu, YiFan Qi

    Earth and Planetary Physics   7 ( 5 )   548 - 557   2023.9   （ ISSN:2096-3955 eISSN:2096-3955 ）

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    At present, the main detection instruments for observing sporadic E (Es) layers are ground-based radars, dense networks of ground-based global navigation satellite system (GNSS) receivers, and GNSS radio occultation, but they cannot capture the whole picture of the horizontal structure of Es layers. This study employs the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension model (WACCM-X 2.1) to derive the horizontal structure of the ion convergence region (HSICR) to explore the shapes of the large-scale Es layers over East Asia for the period from June 1 to August 31, 2008. The simulation produced the various shapes of the HSICRs elongated in the northwest−southeast, northeast−southwest, or composed of individual small patches. The close connection between Es layer critical frequency (foEs) and vertical ion convergence indicates that the HSICR is a good candidate for revealing and explaining the horizontal structure of the large-scale Es layers.

    DOI： 10.26464/epp2023071

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  • Intriguing Aspects of Polar-to-Tropical Mesospheric Teleconnections during the 2018 SSW: A Meteor Radar Network Study

    Eswaraiah, S; Seo, KH; Kumar, KN; Koval, AV; Ratnam, MV; Mengist, CK; Chalapathi, GV; Liu, HX; Kwak, YS; Merzlyakov, E; Jacobi, C; Kim, YH; Rao, SVB; Mitchell, NJ

    ATMOSPHERE   14 ( 8 )   2023.8   （ eISSN:2073-4433 ）

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    Using a network of meteor radar observations, observational evidence of polar-to-tropical mesospheric coupling during the 2018 major sudden stratosphere warming (SSW) event in the northern hemisphere is presented. In the tropical lower mesosphere, a maximum zonal wind reversal (−24 m/s) is noted and compared with that identified in the extra-tropical regions. Moreover, a time delay in the wind reversal between the tropical/polar stations and the mid-latitudes is detected. A wide spectrum of waves with periods of 2 to 16 days and 30–60 days were observed. The wind reversal in the mesosphere is due to the propagation of dominant intra-seasonal oscillations (ISOs) of 30–60 days and the presence and superposition of 8-day period planetary waves (PWs). The ISO phase propagation is observed from high to low latitudes (60° N to 20° N) in contrast to the 8-day PW phase propagation, indicating the change in the meridional propagation of winds during SSW, hence the change in the meridional circulation. The superposition of dominant ISOs and weak 8-day PWs could be responsible for the delay of the wind reversal in the tropical mesosphere. Therefore, this study has strong implications for understanding the reversed (polar to tropical) mesospheric meridional circulation by considering the ISOs during SSW.

    DOI： 10.3390/atmos14081302

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  • Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes

    Juliana Jaen, Toralf Renkwitz, Huixin Liu, Christoph Jacobi, Robin Wing, Aleš Kuchař, Masaki Tsutsumi, Njål Gulbrandsen, Jorge L. Chau

    2023.7

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  • Day-to-day variability of the equatorial ionosphere in Asian sector during August-October 2019

    Liu, HX; Otsuka, Y; Hozumi, K; Yu, T

    FRONTIERS IN ASTRONOMY AND SPACE SCIENCES   10   2023.5   （ ISSN:2296-987X ）

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    This brief report examines the ground-based total electron content (TEC) in Asian sector during August–October 2019, covering the period of a stratosphere sudden warming (SSW) occurred in Antarctica. The analysis reveals pronounced ionospheric day-to-day variability with distinct periodicities. The most dominant and long-lasting periodicities are quasi-10 days and quasi 14-day during September and October, while a quasi 6-day also present in September. The 10-day and 6-day TEC oscillations were attributed by previous studies solely to the Antarctic SSW while assuming negligible geomagnetic effects. By comparing co-located ground mesospheric wind observations, along with the interplanetary electric field (IEF) and geomagnetic activity (Kp index), we demonstrate that the quasi 14-day oscillation is mainly driven by low-level geomagnetic activities, while quasi-6 days oscillation is driven by mesospheric wind changes during the SSW. The 10-day oscillation, on the other hand, is driven by both IEF and mesospheric wind in September, but by IEF in October. These results demonstrate that low-level geomagnetic activities traditionally classified as “quiet conditions” can induce significant day-to-day oscillations in TEC, and their impacts should not be ignored when studying meteorological (e.g., SSWs) impacts on the ionosphere.

    DOI： 10.3389/fspas.2023.1198739

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  • Long-term study of the summer wind variability in the mesosphere and lower thermosphere over nearly two decades at middle and high latitudes

    Juliana Jaen, Toralf Renkwitz, Jorge Chau, Huixin Liu, Christoph Jacobi, Masaki Tsutsumi, Njål Gulbrandsen

    2023.5

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  • Long‐Term Support Is Needed for Crucial Ground‐Based Sensor Networks Reviewed

    J. L. Gannon, S. Morley, N. Lugaz, H. Liu, B. Carter, S. Zou

    Space Weather   21 ( 5 )   2023.5

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    Recently, many in the space weather community have taken up the cause to advocate for an orphan among our own. It’s an important fight—for ground-based sensor networks. Although ground-based sensors are used across all disciplines of space weather, in terms of long-term support, they have no single clear home in any United States agency or department. This has resulted in an ongoing struggle throughout the community to maintain important space weather sensors and networks.

    DOI： 10.1029/2023SW003529

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  • Low Altitude Tailing Es (LATTE): Analysis of Sporadic‐E Layer Height at Different Latitudes of Middle and Low Region Reviewed

    Qiong Tang, Chen Zhou, Huixin Liu, Yi Liu, Jiaqi Zhao, Zhibin Yu, Lianhuan Hu, Zhengyu Zhao, Xueshang Feng

    Space Weather   21 ( 4 )   2023.4   （ eISSN:1542-7390 ）

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    In this paper, the Earth's sporadic-E (Es) layer vertical motion is investigated by using an image processing technique for automatic scaling ionograms from Mohe (122.37°E, 53.50°N, dip angle 71°), Beijing (116.25°E, 40.25°N, dip angle 59°), Wuhan (114.61°E, 30.53°N, dip angle 46°) and Fuke (109.13°E, 19.52°N, dip angle 27°). Es traces descend with different periodicities, indicating tidal modulation to Es layers. Comparing winds from a combination of the Ionospheric Connection Explorer/Michelson Interferometer for Global High-Resolution Thermospheric Imaging and meteor radar measurements with Es layers, we find that Es traces at high altitudes (above 110 km) rapidly move down in accordance with the descent of the wind shear nulls, which indicates the important role of the tides in the formation and descent of the Es layer at high altitude. The lower-lying Es layers, however, do not descend with the wind shear null, but stay at the bottom of the E region (∼100 km) for a long time, which cannot be explained by tidal wind shear theory. In addition, the time duration of the Es layers staying at low latitudes increases with the decreasing latitude. Simulation results demonstrate that the low altitude tailing Es layer is dominated by the dramatically enhanced collision frequency at the lower height of the mesosphere and the lower thermosphere region.

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  • Influence of Mesospheric Gravity Wave Drag on the Formation of Winter Helium Bulge in the Thermosphere Reviewed

    Dexin Ren, Jiuhou Lei, Han‐Li Liu, Wenbin Wang, Jia Yue, Huixin Liu

    Journal of Geophysical Research: Space Physics   128 ( 2 )   2023.2   （ ISSN:2169-9380 eISSN:2169-9402 ）

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    In this study, we focused on the influences of mesospheric gravity wave drag on the winter helium bulge in the thermosphere. The related physical mechanisms are investigated based on the three-dimensional physics-based Thermosphere-Ionosphere-Mesosphere Electrodynamic General Circulation Model. The simulation results suggested that the mesospheric gravity wave drag can contribute to the high amplitude of winter helium bulge due to the intensified summer-to-winter circulation in the thermosphere. It was found that the meridional pressure gradient force, which dominates the generation of thermospheric large-scale circulation, shows an increase when the effect of mesospheric gravity wave drag is considered. The change in thermospheric pressure force is attributed to the mesospheric gravity wave drag related winter-to-summer flow in the lower thermosphere. This intensified summer-to-winter circulation in the thermosphere leads to the decrease and increase of helium concentration in summer and winter, respectively, which thus contributes to the thermospheric winter helium bulge under the effects of mesospheric gravity wave drag.

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  • Credit where credit is due: Data and software in the space weather community Reviewed

    Steven Morley, Huixin Liu, Brett Carter, Jennifer Gannon, Noé Lugaz

    2022.12

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  • Electron density profile reconstruction with convolutional neural networks

    Lan, T; Liu, HQ; Ren, QL; Zhu, X; Mao, WZ; Yuan, Y; Wang, YF

    PLASMA PHYSICS AND CONTROLLED FUSION   64 ( 12 )   2022.12   （ ISSN:0741-3335 eISSN:1361-6587 ）

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  • Credit Where Credit Is Due: Data and Software in the Space Weather Community Reviewed

    S. K. Morley, H. Liu, B. A. Carter, J. L. Gannon, N. Lugaz

    Space Weather   20 ( 12 )   2022.12   （ eISSN:1542-7390 ）

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    This editorial aims to improve awareness of the current best practices in open research, and stimulate discussion on the practical implementation of AGU's data and software policy in key areas of space weather research. We also further aim to encourage authors to take additional steps to ensure clear credit to all contributors to the work, whether that is underlying data, key software, or direct contributions to the manuscript.

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  • Altitude Extension of the NCAR-TIEGCM (TIEGCM-X) and Evaluation

    Cai, YH; Yue, XA; Wang, WB; Zhang, SR; Liu, HX; Lin, D; Wu, HN; Yue, J; Bruinsma, SL; Ding, F; Ren, ZP; Liu, LB

    SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS   20 ( 11 )   2022.11   （ eISSN:1542-7390 ）

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    The upper boundary height of the traditional community general circulation model of the ionosphere-thermosphere system is too low to be applied to the topside ionosphere/thermosphere study. In this study, the National Center for Atmospheric Research Thermosphere-Ionosphere-Electrodynamics General Circulation Model (NCAR-TIEGCM) was successfully extended upward by four scale heights from 400–600 km to 700–1,200 km depending on solar activity, named TIEGCM-X. The topside ionosphere and thermosphere simulated by TIEGCM-X agree well with the observations derived from a topside sounder and satellite drag data. In addition, the neutral density, temperature, and electron density simulated by TIEGCM-X are morphologically consistent with the NCAR-TIEGCM simulations before extension. The latitude-altitude distribution of the equatorial ionization anomaly derived from TIEGCM-X is more reasonable. During geomagnetic storm events, the thermospheric responses of TIEGCM-X are similar to NCAR-TIEGCM. However, the ionospheric storm effects in TIEGCM-X are stronger than those in NCAR-TIEGCM and are even opposites at some middle and low latitudes due to the presence of more closed magnetic field lines. Defense Meteorological Satellite Program observations prove that the ionospheric storm effect of TIEGCM-X is more reasonable. The well-validated TIEGCM-X has significant potential applications in ionospheric/thermospheric studies, such as the responses to storms, low-latitude dynamics, and data assimilation.

    DOI： 10.1029/2022SW003227

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  • 2024 Decadal Survey for Space and Solar Physics: Space Weather Inputs Reviewed

    Noé Lugaz, Jennifer L. Gannon, Shasha Zou, Steven K. Morley, Huixin Liu, Brett A. Carter, Michael Hapgood

    Space Weather   20 ( 8 )   2022.8   （ eISSN:1542-7390 ）

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    The next decadal survey process for space and solar physics will start soon with white papers due during the second half of 2022 and the committees and panels working over all of 2023. Space weather science and operations will play an essential role in this survey. Therefore, the community is invited to prepare white papers and get involved in advancing space weather research and capabilities in the upcoming decades. A summary of the recommendations related to space weather from the last two decadal surveys is also provided.

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  • Thank You to Our 2021 Peer Reviewers

    Noé Lugaz, Brett A. Carter, Jennifer L. Gannon, Michael Hapgood, Huixin Liu, T. Paul O’Brien, Steven K. Morley, Shasha Zou

    Space Weather   20 ( 4 )   2022.4

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    DOI： 10.1029/2022SW003116

  • 昼間スポラディックE層形成過程の中性大気とプラズマ大気の同時観測による解明—Elucidation of the generation process of daytime sporadic E Layers by simultaneous observation of the neutral and ionized atmospheres

    齊藤, 昭則, 阿部, 琢美, 松岡, 彩子, 石坂, 圭吾, 齋藤, 義文, 田川, 雅人, 熊本, 篤志, 斎藤, 享, 西岡, 未知, 細川, 敬祐, 横山, 竜宏, HUIXIN, Liu, SAITO, Akinori, ABE, Takumi, MATSUOKA, Ayako, ISHISAKA, Keigo, SAITO, Yoshifumi, TAGAWA, Masato, KUMAMOTO, Atsushi, SAITO, Susumu, NISHIOKA, Michi, HOSOKAWA, Keisuke, YOKOKAWA, Tatsuhiro

    観測ロケットシンポジウム2021 講演集 = Proceedings of Sounding Rocket Symposium 2021   2022.3

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    第4回観測ロケットシンポジウム（2022年3月14-15日. ハイブリッド開催（JAXA相模原キャンパス& オンライン）)
    4th Sounding Rocket Symposium(March 14-15, 2022. Hybrid(in-person & online) Conference (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan
    著者人数: 12名
    資料番号: SA6000175010
    レポート番号: Ⅱ-5

  • ROLES OF EVENING EASTWARD NEUTRAL WIND AND EQUATORIAL ELECTROJET ON PRE-REVERSAL ENHANCEMENT INFERRED FROM GOCE SATELLITE AND GROUND-BASED OBSERVATIONS

    Abadi, P; Otsuka, Y; Liu, HX; Hozumi, K; Martiningrum, DR

    18TH ANNUAL MEETING OF THE ASIA OCEANIA GEOSCIENCES SOCIETY, AOGS 2021   218 - 220   2022   （ ISBN:978-981-126-009-4 ）

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  • Long-term changes in mesospheric wind and wave estimates based on radar observations in both hemispheres

    Ales Kuchar, Gunter Stober, Christoph Jacobi, Dimitry Pokhotelov, Huxin Liu, Han-Li Liu, Kathrin Baumgarten, Peter Brown, Diego Janches, Damian Murphy, Alexander Kozlovsky, Mark Lester, Evgenia Belova, Johan Kero, Nicholas Mitchell, Tracy Motffat-Griffin

    2021.12

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    DOI： 10.5194/dach2022-81

  • Superposed epoch analysis of coupling mechanisms captured by meteor radars during sudden stratospheric warmings

    Benedikt Gast, Ales Kuchar, Gunter Stober, Christoph Jacobi, Dimitry Pokhotelov, Huxin Liu, Han-Li Liu, Kathrin Baumgarten, Peter Brown, Diego Janches, Damian Murphy, Alexander Kozlovsky, Mark Lester, Evgenia Belova, Johan Kero, Nicholas Mitchell, Tracy Motffat-Griffin

    2021.12

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    DOI： 10.5194/dach2022-84

  • The Possible Role of Turbopause on Sporadic‐E Layer Formation at Middle and Low Latitudes

    Qiong Tang, Chen Zhou, Huixin Liu, Yi Liu, Jiaqi Zhao, Zhibin Yu, Zhengyu Zhao, Xueshang Feng

    Space Weather   19 ( 12 )   2021.12

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    DOI： 10.1029/2021SW002883

  • Machine‐Learning Research in the Space Weather Journal: Prospects, Scope, and Limitations

    Noé Lugaz, Huixin Liu, Mike Hapgood, Steven Morley

    Space Weather   19 ( 12 )   2021.12

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    DOI： 10.1029/2021SW003000

  • Thank You to Our 2020 Reviewers Reviewed

    Noé Lugaz, Delores J. Knipp, Jennifer L. Gannon, Michael Hapgood, Huixin Liu, T. Paul O'Brien, Steven K. Morley

    Space Weather   18 ( 3 )   2021.4

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    DOI： 10.1029/2021SW002756

  • 昼間スポラディックE層形成過程の中性大気とプラズマ大気の同時観測による解明

    斉藤, 昭則, 阿部, 琢美, 石坂, 圭吾, 田川, 雅人, 熊本, 篤志, 齋藤, 義文, 松岡, 彩子, 斎藤, 享, 西岡, 未知, 細川, 敬祐, 横山, 竜宏, HUIXIN, Liu, SAITO, Akinori, ABE, Takumi, ISHISAKA, Keigo, TAGAWA, Masato, KUMAMOTO, Atsushi, SAITO, Yoshifumi, MATSUOKA, Ayako, SAITO, Susumu, NISHIOKA, Michi, HOSOKAWA, Keisuke, YOKOKAWA, Tatsuhiro

    観測ロケットシンポジウム2020 講演集 = Proceedings of Sounding Rocket Symposium 2020   2021.3

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    第3回観測ロケットシンポジウム（2021年3月24-25日. オンライン開催)
    3rd Sounding Rocket Symposium (March 24-25, 2021. Online Meeting)
    著者人数: 12名
    資料番号: SA6000162010
    レポート番号: Ⅲ-3

  • Space Weather as the Nexus of Applied and Fundamental Space Science: The Need for Separate Funding Mechanisms and Definition Reviewed

    Noé Lugaz, Jennifer Gannon, Michael Hapgood, Huixin Liu, T Paul O'Brien

    Space Weather   2020.12

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    DOI： 10.1029/2020SW002695

  • First Global‐Scale Synoptic Imaging of Solar Eclipse Effects in the Thermosphere Reviewed

    Saurav Aryal, J. S. Evans, John Correira, Alan G. Burns, Wenbin Wang, Stanley C. Solomon, Fazlul I. Laskar, William E. McClintock, Richard W. Eastes, Tong Dang, Jiuhou Lei, Huixin Liu, Geonhwa Jee

    Journal of Geophysical Research: Space Physics   125 ( 9 )   2020.9

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    DOI： 10.1029/2020ja027789

  • Thank You to Our 2019 Reviewers Reviewed

    Noé Lugaz, Delores J. Knipp, Jennifer L. Gannon, Michael Hapgood, Huixin Liu, T. Paul O'Brien, Daniel T. Welling

    Space Weather   18 ( 3 )   2020.3

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    Peer reviewing is the foundation of modern scholarship, with external specialists being asked to fairly check and evaluate submitted work. This difficult and often time-consuming activity is performed voluntarily, with the understanding that one's own scholarship shall benefit down the line from a careful analysis of its assumption, results, accuracy, and yes, language, as we are now evaluating someone else's work. At Space Weather, we pride ourselves on a fair but quick review process yielding high-quality articles with a time from submission to first decision of under one month. This would not be possible without the hard work of all our reviewers. Once a year, we take the occasion to name these women and men in order to thank them for their service to the journal and the community.

    DOI： 10.1029/2020SW002481

  • Potential for the measurement of mesosphere and lower thermosphere (MLT) wind, temperature, density and geomagnetic field with Superconducting Submillimeter-Wave Limb-Emission Sounder 2 (SMILES-2) Reviewed

    Philippe Baron, Satoshi Ochiai, Eric Dupuy, Richard Larsson, Huixin Liu, Naohiro Manago, Donal Murtagh, Shin Ichiro Oyama, Hideo Sagawa, Akinori Saito, Takatoshi Sakazaki, Masato Shiotani, Makoto Suzuki

    Atmospheric Measurement Techniques   13 ( 1 )   219 - 237   2020.1

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    Submillimeter-Wave Limb-Emission Sounder 2 (SMILES-2) is a satellite mission proposed in Japan to probe the middle and upper atmosphere (20-160 km). The main instrument is composed of 4K cooled radiometers operating near 0.7 and 2 THz. It could measure the diurnal changes of the horizontal wind above 30 km, temperature above 20 km, ground-state atomic oxygen above 90 km and atmospheric density near the mesopause, as well as abundance of about 15 chemical species. In this study we have conducted simulations to assess the wind, temperature and density retrieval performance in the mesosphere and lower thermosphere (60- 110 km) using the radiometer at 760 GHz. It contains lines of water vapor (H2O), molecular oxygen (O2) and nitric oxide (NO) that are the strongest signals measured with SMILES-2 at these altitudes. The Zeeman effect on the O2 line due to the geomagnetic field (B) is considered; otherwise, the retrieval errors would be underestimated by a factor of 2 above 90 km. The optimal configuration for the radiometer's polarization is found to be vertical linear. Considering a retrieval vertical resolution of 2.5 km, the line-of-sight wind is retrieved with a precision of 2-5ms-1 up to 90 km and 30ms-1 at 110 km. Temperature and atmospheric density are retrieved with a precision better than 5K and 7% up to 90 km (30K and 20% at 110 km). Errors induced by uncertainties on the vector B are mitigated by retrieving it. The retrieval of B is described as a side-product of the mission. At high latitudes, precisions of 30-100 nT on the vertical component and 100-300 nT on the horizontal one could be obtained at 85 and 105 km (vertical resolution of 20 km). SMILES-2 could therefore provide the first measurements of B close to the electrojets' altitude, and the precision is enough to measure variations induced by solar storms in the auroral regions.

    DOI： 10.5194/amt-13-219-2020

  • Potential for the measurement of mesosphere and lower thermosphere (MLT) wind, temperature, density and geomagnetic field with Superconducting Submillimeter-Wave Limb-Emission Sounder 2 (SMILES-2) Reviewed

    Philippe Baron, Satoshi Ochiai, Eric Dupuy, Richard Larsson, Huixin Liu, Naohiro Manago, Donal Murtagh, Shin-ichiro Oyama, Hideo Sagawa, Akinori Saito, Takatoshi Sakazaki, Masato Shiotani, Makoto Suzuki

    Atmospheric Measurement Techniques   13 ( 1 )   219 - 237   2020.1

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    Submillimeter-Wave Limb-Emission Sounder 2 (SMILES-2) is a satellite mission proposed in Japan to probe the middle and upper atmosphere (20-160 km). The main instrument is composed of 4K cooled radiometers operating near 0.7 and 2 THz. It could measure the diurnal changes of the horizontal wind above 30 km, temperature above 20 km, ground-state atomic oxygen above 90 km and atmospheric density near the mesopause, as well as abundance of about 15 chemical species. In this study we have conducted simulations to assess the wind, temperature and density retrieval performance in the mesosphere and lower thermosphere (60-110 km) using the radiometer at 760 GHz. It contains lines of water vapor (H2O), molecular oxygen (O-2) and nitric oxide (NO) that are the strongest signals measured with SMILES-2 at these altitudes. The Zeeman effect on the O-2 line due to the geomagnetic field (B) is considered; otherwise, the retrieval errors would be underestimated by a factor of 2 above 90 km. The optimal configuration for the radiometer's polarization is found to be vertical linear. Considering a retrieval vertical resolution of 2.5 km, the line-of-sight wind is retrieved with a precision of 2-5 m s(-1) up to 90 km and 30 m s(-1) at 110 km. Temperature and atmospheric density are retrieved with a precision better than 5K and 7% up to 90 km (30K and 20% at 110 km). Errors induced by uncertainties on the vector B are mitigated by retrieving it. The retrieval of B is described as a side-product of the mission. At high latitudes, precisions of 30-100 nT on the vertical component and 100-300 nT on the horizontal one could be obtained at 85 and 105 km (vertical resolution of 20 km). SMILES-2 could therefore provide the first measurements of B close to the electrojets' altitude, and the precision is enough to measure variations induced by solar storms in the auroral regions.

    DOI： 10.5194/amt-13-219-2020

  • Correction to El Niño–Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007–2015 FORMOSAT- 3/COSMIC observations (Earth, Planets and Space, (2019), 71, 1, (35), 10.1186/s40623-019-1009-7) Reviewed

    Yang Yi Sun, Huixin Liu, Yasunobu Miyoshi, Loren C. Chang, Libo Liu

    earth, planets and space   71 ( 1 )   2019.12

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    DOI： 10.1186/s40623-019-1025-7

  • Special issue “Recent Advances in MST and EISCAT/Ionospheric Studies – Special Issue of the Joint MST15 and EISCAT18 Meetings, May 2017”

    Mamoru Yamamoto, Wayne K. Hocking, Satonori Nozawa, Juha Vierinen, Huixin Liu, Nozomu Nishitani

    Earth, Planets and Space   71 ( 1 )   2019.12

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    DOI： 10.1186/s40623-019-1070-2

  • Long-Term Trend of Topside Ionospheric Electron Density Derived From DMSP Data During 1995–2017 Reviewed

    Yihui Cai, Xinan Yue, Wenbin Wang, Shunrong Zhang, Libo Liu, Huixin Liu, Weixing Wan

    Journal of Geophysical Research: Space Physics   124 ( 12 )   10708 - 10727   2019.12

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    In recent decades, significant efforts have been made to characterize and understand the global pattern of ionospheric long-term trend. However, little attention has been paid to the topside ionosphere trend. In this study, the unique in situ data measured by series Defense Meteorological Satellite Program (DMSP) satellites were utilized to derive the long-term trend of the topside ionosphere for the first time. We checked carefully data quality, gap, and consistency between different satellites for both electron density and ion temperature, and compared the techniques of artificial neuron network (ANN) and multiple linear regression methods for deriving the trend. The electron density (Ne) trend in the middle and low latitudes at ~860 km around 18 MLT was derived using the ANN method from 1995–2017. The trend from DMSP observations has a mean magnitude ranging from ~ − 2% to ~2% per decade, with clear seasonal, latitude and longitude variations. The derived trend was evaluated by directly comparing with the simulated trend at 500 km from the NCAR-TIEGCM driven by realistic changes of CO2 level and geomagnetic field. The observed and simulated trends have similar geographic distribution patterns at 18 MLT. The good agreement between the observed trend around 860 km and the simulated trend near 500 km implies that the physical processes controlling the Ne trends above the peak height might be identical. Further control simulations show that the geomagnetic field secular variation is the dominant factor of the electron density trend at around 500 km, rather than the CO2 long-term enhancement.

    DOI： 10.1029/2019JA027522

  • Special issue “Recent Advances in MST and EISCAT/Ionospheric Studies – Special Issue of the Joint MST15 and EISCAT18 Meetings, May 2017” Reviewed

    Mamoru Yamamoto, Wayne K. Hocking, Satonori Nozawa, Juha Vierinen, Huixin Liu, Nozomu Nishitani

    earth, planets and space   71 ( 1 )   2019.12

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    DOI： 10.1186/s40623-019-1070-2

  • Thermospheric Density Cells at High Latitudes as Observed by GOCE Satellite: Preliminary Results Reviewed

    Libin Weng, Jiuhou Lei, Huixin Liu, Xiankang Dou, Hanxian Fang

    Geophysical Research Letters   46 ( 21 )   11615 - 11621   2019.11

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    This study provides a climatological view of density cell structures at high latitudes in the lower thermosphere, using neutral mass density at 270 km derived from Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite. Three types of the density cells named isolated low, isolated high, and wavy density cells are analyzed. Our results revealed that the density cell structures generally occur in the Northern Hemisphere and the local summer, but they are less frequently observed in the Southern Hemisphere. The low density cell tends to have greater occurrence in the dawn side than in other sampled local times, while the high and wavy density cells occur more frequently in the morning side in terms of the GOCE trajectory. Moreover, the characteristics of density cell structures, including the central locations, horizontal scales, and relative magnitudes, strongly depend on the type of the density cell structure. These results can serve as a baseline to further validate the theoretical models and also to improve our understanding of the density variability of the lower thermosphere at high latitudes.

    DOI： 10.1029/2019GL084951

  • Special issue "Recent Advances in MST and EISCAT/Ionospheric Studies - Special Issue of the Joint MST15 and EISCAT18 Meetings, May 2017" PREFACE Reviewed

    Mamoru Yamamoto, Wayne K. Hocking, Satonori Nozawa, Juha Vierinen, Huixin Liu, Nozomu Nishitani

    EARTH PLANETS AND SPACE   71 ( 1 )   2019.9

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    DOI： 10.1186/s40623-019-1070-2

  • Thank You to Our 2018 Peer Reviewers Reviewed

    Daniel T. Welling, Delores J. Knipp, Michael Hapgood, Huixin Liu, T. Paul O'Brien

    Space Weather   17 ( 3 )   372 - 374   2019.3

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    DOI： 10.1029/2019SW002194

  • Thank You to Our 2018 Peer Reviewers Reviewed

    Daniel T. Welling, Delores J. Knipp, Michael Hapgood, Huixin Liu, T. Paul O'Brien

    Space Weather   17   372 - 374   2019.3

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    ©2019. American Geophysical Union. All Rights Reserved. Peer review remains one of the most important service activities for scientists. Through the time-consuming process of peer review, community volunteers set the bar for the quality of science that is shared with each other and with the world. Attentive, patient, and critical review is required to maintain rigorous and accurate scientific reporting. Reviewers donate their time and effort with little incentive outside of the knowledge that they are contributing to sustain scientific rigor. Space Weather is fortunate to be able to continually rely on our reviewers to maintain a journal that receives and publishes high-quality, high-impact articles. We recognize the time, effort, and dedication each review requires. For this, we extend a heartfelt thank you to all of our 2018 reviewers. We sincerely appreciate your choice to respond positively to our review requests. Last year, Space Weather received 785 peer reviews from 354 individuals. The reviewers who contributed three or more reviews are recognized in italics below. Thank you all for your contributions in 2018.

    DOI： 10.1029/2019SW002194

  • Observations of Low‐Latitude Traveling Ionospheric Disturbances by a 630.0‐nm Airglow Imager and the CHAMP Satellite Over Indonesia Reviewed

    Aysegul Ceren Moral, Kazuo Shiokawa, Shin Suzuki, Huixin Liu, Yuichi Otsuka, Clara Yoko Yatini

    Journal of Geophysical Research: Space Physics   124 ( 3 )   2198 - 2212   2019.3

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    We report the first comparison of ground and satellite measurements of low-latitude traveling ionospheric disturbances (TIDs). Three TID events were simultaneously observed by a 630.0-nm airglow imager and the CHAllenging Minisatellite Payload (CHAMP) satellite at Kototabang, Indonesia (geographic coordinates: 0.2 degrees S, 100.3 degrees E, geomagnetic latitude: 10.6 degrees S). In 630.0-nm airglow images of all three events, there are clear southward-moving structures. Events 1 and 2 are a single pulse with horizontal scales of similar to 500-1,000 km. Event 3 shows five wave fronts with a horizontal scale size of 500-1,000 km. All three TIDs are medium-scale TIDs. Horizontal wavelengths of both airglow intensity at an average emission altitude of 250 km and CHAMP neutral density variations measured at 400 km are estimated by fitting a sinusoidal function to the observed data. The estimated horizontal wavelengths for airglow and neutral density data are 1,031 and 880 km for event 1 and 560 and 420 km for event 3, respectively. These values between airglow and CHAMP are comparable, suggesting both instruments are observing the same wave. For event 1, the CHAMP electron density mapped along the geomagnetic field line onto the airglow altitude does not show wave structure similar to the airglow variation. For events 2 and 3, the plasma density did not show wavy structures similar to the waves seen in the airglow image and CHAMP neutral density. These results suggest that the TIDs observed in airglow images are not caused by ionospheric plasma instability but by gravity waves in the thermosphere.

    DOI： 10.1029/2018JA025634

  • Precursor effect of March 11 2011 off the coast of Tohoku earthquake on high and low latitude ionospheres and its possible disturbing mechanism Reviewed

    Oyama, K, C. H. Chen, L. Bankov, D. Minakshi, K. Ryu, J.Y. Liu, Huixin Liu

    Advances in Space Research   63   2019.1

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    Precursor effect of March 11 2011 off the coast of Tohoku earthquake on high and low latitude ionospheres and its possible disturbing mechanism

  • Special issue “Akatsuki at Venus The First Year of Scientific Operation” Reviewed

    Masato Nakamura, Dmitri Titov, Kevin McGouldrick, Pierre Drossart, Jean Loup Bertaux, Huixin Liu

    earth, planets and space   70 ( 1 )   2018.12

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    DOI： 10.1186/s40623-018-0916-3

  • Generation of Electron Acoustic Waves in the Topside Ionosphere From Coupling With Kinetic Alfven Waves: A New Electron Energization Mechanism Reviewed

    Run Shi, Binbin Ni, Danny Summers, Huixin Liu, Akimasa Yoshikawa, Beichen Zhang

    Geophysical Research Letters   45 ( 11 )   5299 - 5304   2018.6

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    Results from a new drift kinetic model in the topside ionosphere capture the mode conversion from kinetic Alfven waves to electron acoustic waves. When the kinetic Alfven waves propagate into the transition region, where the electron density of ionospheric origin becomes comparable to that of magnetospheric origin, the steep temperature gradient leads to the mode conversion. The electron acoustic waves are short-lived by dissipating their energy into the electron energization, thus revealing a new type of electron acceleration in the topside ionosphere.

    DOI： 10.1029/2018GL077898

  • Modifications of the ionosphere prior to large earthquakes report from the Ionosphere Precursor Study Group Reviewed

    K. I. Oyama, M. Devi, K. Ryu, C. H. Chen, J. Y. Liu, H. Liu, L. Bankov, T. Kodama

    Geoscience Letters   3 ( 1 )   2016.12

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    The current status of ionospheric precursor studies associated with large earthquakes (EQ) is summarized in this report. It is a joint endeavor of the “Ionosphere Precursor Study Task Group,” which was formed with the support of the Mitsubishi Foundation in 2014–2015. The group promotes the study of ionosphere precursors (IP) to EQs and aims to prepare for a future EQ dedicated satellite constellation, which is essential to obtain the global morphology of IPs and hence demonstrate whether the ionosphere can be used for short-term EQ predictions. Following a review of the recent IP studies, the problems and specific research areas that emerged from the one-year project are described. Planned or launched satellite missions dedicated (or suitable) for EQ studies are also mentioned.

    DOI： 10.1186/s40562-016-0038-3

  • Alfvén waves as a solar-interplanetary driver of the thermospheric disturbances Reviewed

    Jianpeng Guo, Fengsi Wei, Xueshang Feng, Huixin Liu, Weixing Wan, Zhiliang Yang, Jiyao Xu, Chaoxu Liu

    Scientific reports   6   2016.1

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    Alfvén waves have been proposed as an important mechanism for the heating of the Sun's outer atmosphere and the acceleration of solar wind, but they are generally believed to have no significant impact on the Earth's upper atmosphere under quiet geomagnetic conditions due to their highly fluctuating nature of interplanetary magnetic field (i.e., intermittent southward magnetic field component). Here we report that a long-duration outward propagating Alfvén wave train carried by a high-speed stream produced continuous (∼2 days) and strong (up to ±40%) density disturbances in the Earth's thermosphere in a way by exciting multiple large-scale gravity waves in auroral regions. The observed ability of Alfvén waves to excite large-scale gravity waves, together with their proved ubiquity in the solar atmosphere and solar wind, suggests that Alfvén waves could be an important solar-interplanetary driver of the global thermospheric disturbances.

    DOI： 10.1038/srep18895

  • Precursory enhancement of EIA in the morning sector Contribution from mid-latitude large earthquakes in the north-east Asian region Reviewed

    Kwangsun Ryu, Koh Ichiro Oyama, Ludmil Bankov, Chia Hung Chen, Minakshi Devi, Huixin Liu, Jann Yenq Liu

    Advances in Space Research   57 ( 1 )   268 - 280   2016.1

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    To investigate whether the link between seismic activity and EIA (equatorial ionization anomaly) enhancement is valid for mid-latitude seismic activity, DEMETER observations around seven large earthquakes in the north-east Asian region were fully analyzed (M⩾6.8). In addition, statistical analysis was performed for 35 large earthquakes (M⩾6.0) that occurred during the DEMETER observation period. The results suggest that mid-latitude earthquakes do contribute to EIA enhancement, represented as normalized equatorial N e , and that ionospheric change precedes seismic events, as has been reported in previous studies. According to statistical studies, the normalized equatorial density enhancement is sensitive and proportional to both the magnitude and the hypocenter depth of an earthquake. The mechanisms that can explain the contribution of mid-latitude seismic activity to EIA variation are briefly discussed based on current explanations of the geochemical and ionospheric processes involved in lithosphere–ionosphere interaction.

    DOI： 10.1016/j.asr.2015.08.030

  • Empirical model of equatorial electrojet based on ground-based magnetometer data during solar minimum in fall Reviewed

    Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Akimasa Yoshikawa

    EARTH PLANETS AND SPACE   67   2015.12

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    In this study, we constructed an empirical model of the equatorial electrojet (EEJ), including local time and longitudinal dependence, based on simultaneous data from 12 magnetometer stations located in six longitude sectors. An analysis was carried out using the equatorial electrojet index, EUEL, calculated from the geomagnetic northward H component. The magnetic EEJ strength is calculated as the difference between the normalized EUEL index of the magnetic dip equator station and the normalized EUEL index of the off-dip equator station located beyond the EEJ band. Analysis showed that this current is always strongest in the South American sector, regardless of local time (LT), and weakest in the Indian sector during 0900 and 1000 LT, but shifted to the African sector during 1100 to 1400 LT. These longitude variations of EEJ roughly follow variations of the inversed main field strength along the dip equator, except for the Indian and Southeast Asian sectors. The result showed that the EEJ component derived from the model exhibits a similar pattern with measured EEJ from ground data during noontime, mainly before 1300 LT.

    DOI： 10.1186/s40623-015-0373-1

  • Longitudinal and solar activity dependence of equatorial electrojet at Southeast Asian sector

    N. S.A. Hamid, H. Liu, T. Uozumi, G. K. Gopir, H. A. Hadin, A. Yoshikawa

    4th International Conference on Space Science and Communication, IconSpace 2015 2015 International Conference on Space Science and Communication Space Technology for Humanity, IconSpace 2015 - Proceeding   262 - 266   2015.9

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    In the E layer of equatorial ionosphere, the equatorial electrojet (EEJ) current interacts with the global Sq current and caused abnormally large amplitude of geomagnetic field component measured at the magnetic dip equator station. In this study, we attempted to separate EEJ and Sq at dip equator using the EUEL index derived from MAGDAS/CPMN stations. Moreover, we normalized the observation data to overcome the uncertainties due to the latitudinal variation of both EEJ and Sq currents which are neglected in most of previous studies. This new approach allowed the study of longitudinal dependence of EEJ. Analysis is performed using data from stations at East and West of Southeast Asian sector for a year of 2011. Additionally, we examined the solar activity dependence of EEJ during this inclining phase of solar cycle.

    DOI： 10.1109/IconSpace.2015.7283763

  • Possible correlation between exogenous parameters and seismicity

    Mohamad Huzaimy Jusoh, Farah Adilah Mohd Kasran, Huixin Liu, Kiyohumi Yumoto

    7th International Conference on Recent Advances in Space Technologies, RAST 2015 RAST 2015 - Proceedings of 7th International Conference on Recent Advances in Space Technologies   525 - 529   2015.8

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    Exogenous parameter is basically referred to the external activities that may have been the important factors in modulating the atmosphere, ionosphere and the earth's surface. Due to its significant impacts, there is possibility to link solar activities and seismicity. Associated investigations have been done by previous researchers in order to explore the solar - terrestrial connection; nevertheless, the physical mechanism is still controversial. To comprehend the investigation of this coupling mechanism, we propose another exogenous source to be analyzed which is cosmic ray. As solar activity, cosmic ray also has minimum and maximum phases or called as cosmic ray cycle, but it is anti-correlation between phases of sunspot and cosmic ray cycles. In this brief report, we examine the trend of shallow earthquake occurrence as the caused effect during recent 4 complete solar cycles (SC 20-23) in order to study its possible link to sun spot number (SSN). The earthquakes were categorized into very shallow earthquakes with epicenter depth less than 35 km and deeper earthquakes with epicenter depth between 35-70 km. For very shallow earthquakes, the analysis shows two interesting features. First, its occurrence rate shows a steady increase during the 40 years period of 1964-2005, with average increase rate about 150/year. Second, a distinct increase of the occurrence rate occurs during each solar minimum of SC 21-23. Neither of these features is found in the earthquakes with deeper epicenters, suggesting that the solar influence on seismicity, if exists, is likely to exist only in the case of very shallow earthquakes whose epicenter is in the crust region.

    DOI： 10.1109/RAST.2015.7208401

  • Structure and origins of the Weddell Sea Anomaly from tidal and planetary wave signatures in FORMOSAT-3/COSMIC observations and GAIA GCM simulations Reviewed

    Loren C. Chang, Huixin Liu, Yasunobu Miyoshi, Chia Hung Chen, Fu Yuan Chang, Chien Hung Lin, Jann Yenq Liu, Yan Yi Sun

    Journal of Geophysical Research: Space Physics   120 ( 2 )   1325 - 1340   2015.2

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    The Weddell Sea Anomaly (WSA) is a recurrent feature of the austral summer midlatitude ionosphere where electron densities are observed to maximize during the local nighttime. In this study, tidal decomposition is applied to FORMOSAT-3 (Formosa Satellite)/Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) total electron content (TEC) and electron density observations between 2007 and 2012 to quantify the components dominating local time and spatial variation in the WSA region. Our results present some of the first three-dimensional spaceborne analyses of the WSA from a tidal perspective over multiple years. We find that the features of the WSA can be reconstructed as the result of superposition between the dominant diurnal standing (D0), eastward wave number 1 (DE1), westward wave number 2 (DW2), and stationary planetary wave 1 (SPW1) components in TECs, producing the characteristic midnight WSA peak. The D0, DE1, DW2, and SPW1 components are found to be an interannually recurring feature of the southern midlatitude to high-latitude ionosphere during the summer, manifesting as enhancements in electron density around 300km altitude of the summer middle to high magnetic latitudes. The phases of the aforementioned nonmigrating diurnal signatures in electron density in this region are near evanescent, suggesting in situ generation, rather than upward propagation from below. However, the SPW1 signature shows some signs of an eastward tilt with altitude, suggesting possible downward propagation. The relation of these components to possible generation via in situ photoionization or plasma transport along magnetic field lines is also discussed using results from the Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy (GAIA) general circulation model (GCM), connecting the tidal interpretation of the WSA to previously examined generation mechanisms.

    DOI： 10.1002/2014JA020752

  • Ionospheric shock waves triggered by rockets Reviewed

    C. H. Lin, J. T. Lin, C. H. Chen, J. Y. Liu, Y. Y. Sun, Y. Kakinami, M. Matsumura, W. H. Chen, H. Liu, R. J. Rau

    Annales Geophysicae   32 ( 9 )   1145 - 1152   2014.9

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    This paper presents a two-dimensional structure of the shock wave signatures in ionospheric electron density resulting from a rocket transit using the rate of change of the total electron content (TEC) derived from ground-based GPS receivers around Japan and Taiwan for the first time. From the TEC maps constructed for the 2009 North Korea (NK) Taepodong-2 and 2013 South Korea (SK) Korea Space Launch Vehicle-II (KSLV-II) rocket launches, features of the V-shaped shock wave fronts in TEC perturbations are prominently seen. These fronts, with periods of 100-600 s, produced by the propulsive blasts of the rockets appear immediately and then propagate perpendicularly outward from the rocket trajectory with supersonic velocities between 800-1200 ms(-1) for both events. Additionally, clear rocket exhaust depletions of TECs are seen along the trajectory and are deflected by the background thermospheric neutral wind. Twenty minutes after the rocket transits, delayed electron density perturbation waves propagating along the bow wave direction appear with phase velocities of 800-1200 ms(-1). According to their propagation character, these delayed waves may be generated by rocket exhaust plumes at earlier rocket locations at lower altitudes.

    DOI： 10.5194/angeo-32-1145-2014

  • Constructive interference of large-scale gravity waves excited by interplanetary shock on 29 October 2003: CHAMP observation Reviewed

    Jianpeng Guo, Huixin Liu, Xueshang Feng, Weixing Wan, Yue Deng, Chaoxu Liu

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   119 ( 8 )   2014.8

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    In this paper we report the detection of full constructive interference between two large-scale gravity waves in the upper thermosphere from the CHAMP accelerometer measurements. The two waves are separately excited in northern and southern auroral regions by the shock-induced auroral intensification on 29 October 2003. They propagate equatorward and encounter near the equator, where constructive interference occurs and causes nightside equatorial neutral density enhancements of similar to 60%. This result demonstrates that the constructive interference can be a potential mechanism for large density increases in the equatorial region during magnetically active periods.

    DOI： 10.1002/2014JA020255

  • Thermal and dynamical changes of the zonal mean state of the thermosphere during the 2009 SSW: GAIA simulations Reviewed

    Huixin Liu, Yasunobu Miyoshi, Saburo Miyahara, Hidekatsu Jin, Hitoshi Fujiwara, Hiroyuki Shinagawa

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   119 ( 8 )   2014.8

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    Changes of the zonal mean state of the thermosphere during the 2009 stratospheric sudden warming (SSW) have been investigated using the Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy (GAIA) model. Both the zonal mean thermal and dynamical structure of the thermosphere exhibit pronounced changes during the SSW in terms of zonal mean temperature and winds. First, the zonal mean temperature above 100 km altitude drops at all latitudes except for in a narrow band around 60 degrees N. Such temperature perturbations are found to be dominantly caused by changes in direct heating/cooling processes related to solar radiation and thermal heat conduction at high latitudes, but by dynamical processes in tropical regions. Second, the zonal mean zonal wind experiences a strong westward perturbation in the tropical thermosphere, along with distinct change in the meridional circulation. This change consists of two parts. One is a global scale north-to-south flow accompanied with upwelling/downwelling in the northern/southern polar region, the other is a fountain-like flow in tropical lower thermosphere. The large enhancement of semidiurnal tides is suggested to be the primary cause for the fountain-like flow.

    DOI： 10.1002/2014JA020222

  • MLT and seasonal dependence of auroral electrojets: IMAGE magnetometer network observations Reviewed

    Jianpeng Guo, Huixin Liu, Xueshang Feng, T. I. Pulkkinen, E. I. Tanskanen, Chaoxu Liu, Dingkun Zhong, Yuan Wang

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   119 ( 4 )   3179 - 3188   2014.4

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    Total eastward and westward electrojet currents (EEJ and WEJ) and their central latitudes derived from the International Monitor for Auroral Geomagnetic Effects (IMAGE) network magnetic measurements are analyzed for the combined MLT (magnetic local time) and seasonal dependence during the period 1995-2009. EEJ shows a strong MLT variation with significant dependence on season. During summer months the maxima occur around 1600-1800 MLT, whereas during winter months the maxima occur around 1800-2000 MLT. Moreover, the summer maxima are much larger than the winter maxima and appear at higher latitudes. The summer maxima are mainly associated with the solar EUV conductivity effect, while the winter maxima are mainly due to the contribution of northward convective electric field. EEJ exhibits a dominant annual variation with maximum in summer and minimum in winter. WEJ also exhibits a strong MLT variation with significant dependence on season. The maxima occur around 0200-0400 MLT during summer months, around 0000-0200 MLT during winter months, and around 0000-0400 MLT during equinoctial months. Moreover, the equinoctial maxima are much larger than the summer and winter maxima and appear at relatively lower latitudes. The seasonal variations in WEJ are the combinations of annual variations and semiannual variations. Both annual and semiannual variations show significant dependence on MLT. These results increase our knowledge on what factors contribute to the auroral electrojets as well as their magnetic signatures and hence help us better understand the limitations of global auroral electrojet indices, such as the AE and SME indices.

    DOI： 10.1002/2014JA019843

  • Annual variations in westward auroral electrojet and substorm occurrence rate during solar cycle 23 Reviewed

    Jianpeng Guo, T. I. Pulkkinen, E. I. Tanskanen, Xueshang Feng, Barbara A. Emery, Huixin Liu, Chaoxu Liu, Dingkun Zhong

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   119 ( 3 )   2061 - 2068   2014.3

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    The International Monitor for Auroral Geomagnetic Effects network magnetic measurements during the period 1995-2009 are used to characterize the annual variations in the westward electrojet. The results suggest that the annual variations in different local time sectors are quite different due to the different sources. In the MLT sector 2200-0100, the annual variations with maxima in winter suggest they are caused by the combined effects of the convective electric field and the conductivity associated with particle precipitation. Furthermore, the conductivity seems to play a more important role in the MLT sector similar to 2200-2320, while the convective electric field appears to be more important in the MLT sector similar to 2320-0100. In the MLT sector 0300-0600, the annual variations with maxima in summer suggest they are caused by solar EUV conductivity effect and the equinoctial effect. The solar EUV conductivity effect works by increasing ionospheric conductivity and enhancing the westward electrojet in summer, while the equinoctial effect works by decreasing solar wind-magnetosphere coupling efficiency and weakening the westward electrojet in winter. In the MLT sector 0100-0300, the annual variations are relatively weak and can be attributed to the combined effects of annual variations caused by all the previously mentioned effects. In addition, we find that a significant annual variation in substorm occurrence rate, mainly occurring in the premidnight region, is quite similar to that in the westward electrojet. We suggest that elevated solar wind driving during the winter months contributes to higher substorm occurrence in winter in the Northern Hemisphere.

    DOI： 10.1002/2013JA019742

  • 電離圏擾乱における中性大気とプラズマ結合の重要性

    Liu Huixin, 児玉 哲哉, 鴨川 仁

    宇宙科学技術連合講演会講演集   57   3p   2013.10

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    The Importance of Plasma-Neutral Coupling in Understanding Ionospheric Disturbances

  • Coupling of electrons and inertial Alfven waves in the topside ionosphere Reviewed

    Run Shi, Huixin Liu, A. Yoshikawa, Beichen Zhang, Binbin Ni

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   118 ( 6 )   2903 - 2910   2013.6

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    A one-dimensional kinetic model is constructed to simulate the electron acceleration by inertial Alfven waves. The electrons are divided into cold and hot electrons and treated separately. Cold components are described by the fluid equation and hot ones by the Vlasov equation, both carrying field-aligned currents. Intense variation of Alfven speed has been introduced by inclusion of cold electrons. The model results show that the exponential decrease of the plasma density plays a key role, which leads to the sharp gradient of both Alfven velocity and electron inertial length. When Alfven waves encounter this sharp gradient at lower altitudes, the electrons accelerated by the waves become super-Alfvenic, and the width of burst structures becomes much wider than the electron inertial length. Consequently, the background electrons carry the oppositely field-aligned current due to plasma oscillation. It is demonstrated that the current carried by the electrons exceeding the wavefront is balanced by the reverse current carried by background electrons. This mechanism can be used to reasonably explain observations of the electron bursts accompanied by little net field-aligned current. Furthermore, our simulation indicates another type of Alfven wave reflection due to mirror force and wave-particle interaction.

    DOI： 10.1002/jgra.50355

  • Empirical model of the thermospheric mass density based on CHAMP satellite observations Reviewed

    Huixin Liu, Takashi Hirano, Shigeto Watanabe

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   118 ( 2 )   843 - 848   2013.2

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    The decadal observations from CHAMP satellite have provided ample information on the Earth's upper thermosphere, reshaping our understandings of the vertical coupling in the atmosphere and near-Earth space. An empirical model of the thermospheric mass density is constructed from these high-resolution observations using the multivariable least-squares fitting method. It describes the density variation with latitude, longitude, height, local time, season, and solar and geomagnetic activity levels within the altitude range of 350-420 km. It represents well prominent thermosphere structures like the equatorial mass density anomaly (EMA) and the wave-4 longitudinal pattern. Furthermore, the empirical model reveals two distinct features. First, the EMA is found to have a clear altitude dependence, with its crests moving equatorward with increasing altitude. Second, the equinoctial asymmetry is found to strongly depend on solar cycle, with its magnitude and phase being strongly regulated by solar activity levels. The equinoctial density maxima occur significantly after the actual equinox dates toward solar minimum, which may signal growing influence from the lower atmosphere forcing. This empirical model provides an instructive tool in exploring thermospheric density structures and dynamics. It can also be easily incorporated into other models to have a more accurate description of the background thermosphere, for both scientific and practical purposes. Citation: Liu, H., T. Hirano, and S. Watanabe (2013), Empirical model of the thermospheric mass density based on CHAMP satellite observation, J. Geophys. Res. Space Physics, 118, 843-848, doi: 10.1002/jgra.50144.

    DOI： 10.1002/jgra.50144

  • Electromagnetic coupling on solar-terrestrial system: Possible effects on seismic activities

    M. H. Jusoh, K. Yumoto, N. S Abdul Hamid, H. Liu

    IEEE Antennas and Propagation Society, AP-S International Symposium (Digest)   1160 - 1163   2012.12

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    Electromagnetic coupling on solar-terrestrial system: Possible effects on seismic activities
    Solar wind parameters play significant roles in electromagnetic coupling of the Sun - Earth system. By having a long period of observation and analysis of solar activities and its influence on geomagnetic or seismic activities, it is possible to reveal the interconnection between them. In the present paper, we analyzed the earthquake (EQ) events as seismic parameters, which extracted from Advanced National Seismic System (ANSS) database. The different earthquake magnitudes were analyzed with the solar parameters; high-speed solar wind (HSSW) events, and solar wind dynamic pressure (SW Pdyn). All of these analyses were done from year 1964 to 2008, which covers the latest entire solar cycles (cycle number 20 to 23). In the analysis, we propose how the electromagnetic energy can be transferred from the solar wind to the lower ionosphere and finally affected the geomagnetic activities by showing the plots and the statistical analysis on plasma speed event (Vsw), solar wind dynamic pressure (SW Pdyn), solar wind input energy and ring current (Dst) index. The analyzed results show a significant relationship between solar and terrestrial parameters. © 2012 IEICE.

  • Sq current system during stratospheric sudden warming events in 2006 and 2009 Reviewed

    Yosuke Yamazaki, Arthur D. Richmond, Huixin Liu, Kiyohumi Yumoto, Yoshimasa Tanaka

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   117   2012.12

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    Ionospheric Sq current systems during unusually strong and prolonged stratospheric sudden warming (SSW) events in January 2006 and January 2009 are examined by analyzing ground-magnetometer data for the American and Asian longitude sectors. During these SSW events, a significant decrease and increase of the Sq equivalent current intensity are observed in the Northern and Southern Hemispheres, respectively, along with a reduction in the longitudinal separation between the northern and southern current vortices. Numerical experiments using the National Center for Atmospheric Research Thermosphere-Ionosphere-Electrodynamics General-Circulation Model show that changes in the solar anti-symmetric (2,3) semidiurnal tide can bring about similar changes in the Sq current system. Citation: Yamazaki, Y., A. D. Richmond, H. Liu, K. Yumoto, and Y. Tanaka (2012), Sq current system during stratospheric sudden warming events in 2006 and 2009, J. Geophys. Res., 117, A12313, doi:10.1029/2012JA018116.

    DOI： 10.1029/2012JA018116

  • First observational evidence for opposite zonal electric fields in equatorial E and F region altitudes during a geomagnetic storm period

    S. Tulasi Ram, N. Balan, B. Veenadhari, S. Gurubaran, S. Ravindran, T. Tsugawa, H. Liu, K. Niranjan, T. Nagatsuma

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   117   2012.9

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    The strong westward electrojet and simultaneous upward drift of the equatorial ionospheric peak observed over South-East Asia and Indian equatorial regions during the prolonged Dst minimum phase of an intense geomagnetic storm during 14-15 December 2006 are investigated for the altitudinal variation of zonal electric field polarity using ground based and space-borne observations. The results show first observational evidence for simultaneous existence of daytime westward and eastward zonal electric fields at equatorial E and F region altitudes, respectively, in a wide longitude sector. While the westward electric fields at E region altitudes cause westward electrojet, at the same time, the eastward zonal electric fields at F region altitudes cause the upward drift of the equatorial ionospheric peak and reinforcement of the equatorial ionization anomaly (EIA) even in the topside ionosphere (similar to 660 km). The reversal of the electric fields is found to occur at similar to 280 km height. A clear bifurcation of F region plasma at similar to 280 km is evident in the iso-electron density contours due to these oppositely polarized zonal electric fields, which manifests as an unusually deep cusp between F-1 and F-2 layers on equatorial ionograms. Citation: Tulasi Ram, S., N. Balan, B. Veenadhari, S. Gurubaran, S. Ravindran, T. Tsugawa, H. Liu, K. Niranjan, and T. Nagatsuma (2012), First observational evidence for opposite zonal electric fields in equatorial E and F region altitudes during a geomagnetic storm period, J. Geophys. Res., 117, A09318, doi:10.1029/2012JA018045.

    DOI： 10.1029/2012JA018045

  • Numerical simulation of the equatorial wind jet in the thermosphere Reviewed

    Yasunobu Miyoshi, Hitoshi Fujiwara, Hidekatsu Jin, Hiroyuki Shinagawa, Huixin Liu

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   117   2012.3

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    We have examined excitation mechanism of the fast jet of the neutral atmosphere along the dip equator in the upper thermosphere. The zonal momentum balance of the neutral atmosphere is estimated using an atmosphere-ionosphere coupled model. The coupled model used in this study is a self-consistent global model of the atmosphere and ionosphere covering the height range from the ground surface to the exobase. It can reproduce the observed equatorial fast jet above 250 km heights. The analysis of the zonal momentum balance reveals that the pressure gradient and ion drag play an important role on the formation of the fast jet near the dip equator. In particular, the fast jet near the equator is closely related with the latitudinal difference of the ion drag force. We also investigate the zonal momentum balance of the longitudinal wave-4 structure of the zonal wind in the fixed local time frame. Furthermore, significant day-to-day variations in the neutral zonal wind and the ion drift near the dip equator are obtained although the solar UV/EUV fluxes and the energy input from the magnetosphere are assumed to be constant during the numerical simulation. This result indicates the importance of the lower atmospheric variability on day-to-day variations in the thermosphere/ionosphere.

    DOI： 10.1029/2011JA017373

  • Equatorial electrodynamics and neutral background in the Asian sector during the 2009 stratospheric sudden warming Reviewed

    Huixin Liu, Mamoru Yamamoto, S. Tulasi Ram, Takuya Tsugawa, Yuichi Otsuka, Claudia Stolle, Eelco Doornbos, Kiyohumi Yumoto, Tsutomu Nagatsuma

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   116   2011.8

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    Using ground observations of total electron content (TEC) and equatorial electrojet (EEJ) in the Asian sector, along with plasma and neutral densities obtained from the CHAMP satellite, we investigate the ionospheric electrodynamics and neutral background in this longitude sector during the major stratospheric sudden warming (SSW) in January 2009. Our analysis reveals the following prominent features. First, the TEC response in tropical regions is strongly latitude dependent, with monotonic depletion at the dip equator but a semidiurnal perturbation at low latitudes. Second, the TEC semidiurnal perturbation possesses a significant hemispheric asymmetry in terms of onset date and magnitude. It starts on the same day as the SSW peak in the Northern Hemisphere but 2 days later in the Southern Hemisphere. Its magnitude is twice as strong in the north than in the south. Third, strong counter electrojet occurs in the afternoon, following the strengthening of the eastward EEJ in the morning. Fourth, semidiurnal perturbation in both TEC and EEJ possesses a phase shift, at a rate of about 0.7 h/day. Comparisons with results reported in the Peruvian sector reveal clear longitude dependence in the amplitude and hemispheric asymmetry of the semidiurnal perturbation. Finally, thermospheric density undergoes similar to 25% decrease at low latitudes in the afternoon local time sector during the SSW, indicating significant cooling effects in the tropical upper thermosphere.

    DOI： 10.1029/2011JA016607

  • Comment on "Westward electric field penetration to the dayside equatorial ionosphere during the main phase of the geomagnetic storm on 22 July 2009" by V. Sreeja et al Reviewed

    S. Tulasi Ram, M. Yamamoto, H. Liu, B. Veenadhari, S. Alex

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   116   2011.6

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    Sreeja et al. [2011] have claimed that the "geomagnetic storm that occurred during the period from 21 to 25 July 2009 is anomalous because the storm main phase developed during northward interplanetary magnetic field (IMF)" and "westward electric field penetration to the day-side equatorial ionosphere during the main phase of the storm." However, as discussed subsequently, the so-called "anomalous" feature of geomagnetic storm is ill-fully claimed due to their incorrect IMF B(z) data. Since Sreeja et al. [2011] have made serious claims such as the geomagnetic storm of 21-25 July 2009 is anomalous which would have adverse impact on the future scientific investigations, it is highly necessary to clarify.

    DOI： 10.1029/2011JA016634

  • On the formation of a fast thermospheric zonal wind at the magnetic dip equator

    Kondo T., Richmond A. D., Liu H., Lei J., Watanabe S.

    Geophysical Research Letters   38   L10101   2011.5

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    On the formation of a fast thermospheric zonal wind at the magnetic dip equator

    DOI： 10.1029/2011GL047255

  • Midnight latitude-altitude distribution of 630 nm airglow in the Asian sector measured with FORMOSAT-2/ISUAL Reviewed

    Toru Adachi, Masashi Yamaoka, Mamoru Yamamoto, Yuichi Otsuka, Huixin Liu, Chun-Chieh Hsiao, Alfred B. Chen, Rue-Ron Hsu

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   115   2010.9

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    The Imager for Sprites and Upper Atmospheric Lightning (ISUAL) payload on board the FORMOSAT-2 satellite carried out the first limb imaging observation of 630 nm airglow for the purpose of studying physical processes in the F region ionosphere. For a total of 14 nights in 2006-2008, ISUAL scanned the midnight latitude-altitude distribution of 630 nm airglow in the Asian sector. On two nights of relatively active conditions (Sigma Kp = 26, 30+) we found several bright airglow regions, which were highly variable each night in terms of luminosity and location. In relatively quiet conditions (Sigma Kp = 4-20) near May/June we found two bright regions which were stably located in the midlatitude region of 40 degrees S-10 degrees S (50 degrees S-20 degrees S magnetic latitude (MLAT)) and in the equatorial region of 0 degrees-10 degrees N (10 degrees S-0 degrees MLAT). On one of the quiet nights, FORMOSAT-3/COSMIC and CHAMP simultaneously measured the plasma density in the same region where ISUAL observed airglow. The plasma density data generally show good agreement, suggesting that plasma enhancements were the primary source of these two bright airglow regions. From detailed comparison with past studies we explain that the airglow in the equatorial region was due to the midnight brightness wave produced in association with the midnight temperature maximum, while that in the midlatitude region was due to the typical plasma distribution usually formed in the midnight sector. The fact that the equatorial airglow was much brighter than the midlatitude airglow and was observed on most nights during the campaign period strongly suggests the importance of further studies on the MTM/MBW phenomenology, which is not well reproduced in the current general circulation model.

    DOI： 10.1029/2009JA015147

  • Nighttime-like quasi periodic echoes induced by a partial solar eclipse Reviewed

    Smitha V. Thampi, Mamoru Yamamoto, Huixin Liu, Susumu Saito, Yuichi Otsuka, Amit Kumar Patra

    GEOPHYSICAL RESEARCH LETTERS   37   2010.5

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    The first observations of solar eclipse induced mid-latitude plasma irregularities using the middle and upper atmosphere radar (MU radar) at Shigaraki (34.85 degrees N, 136.1 degrees E, 25.0 degrees N geomagnetic) are presented. The observations were done during the partial solar eclipse on 22 July, 2009. The observations show that the sudden withdrawal of solar radiation could deplete the background E-region densities, thereby unmasking the long-lived metallic ions within the strong and patchy Sporadic E-layers. As a result of this, Quasi-Periodic (QP) echoes were generated, which were detected by the MU radar. These echoes resemble the normal post-sunset QP echoes observed over mid-latitudes as revealed by the multi-channel interfereometry imaging. This example shows that over mid-latitudes E-region plasma irregularities can be generated during a partial solar eclipse, revealing a hitherto unobserved aspect of mid-latitude ionospheric responses to eclipses. Citation: Thampi, S. V., M. Yamamoto, H. Liu, S. Saito, Y. Otsuka, and A. K. Patra (2010), Nighttime-like quasi periodic echoes induced by a partial solar eclipse, Geophys. Res. Lett., 37, L09107, doi: 10.1029/2010GL042855.

    DOI： 10.1029/2010GL042855

  • Phase reversal of the diurnal cycle in the midlatitude ionosphere Reviewed

    Huixin Liu, Smitha V. Thampi, Mamoru Yamamoto

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   115   2010.1

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    The typical diurnal cycle of the midlatitude F region electron density consists of a midday maximum and a midnight minimum. However, a phase reversal of this diurnal cycle has been found to occur in three distinct regions on the globe. They are the East Asian (EA) region centered around (53 degrees N, 150 degrees E), the Northern Atlantic (NA) region centered around (45 degrees N, 50 degrees W) and the South Pacific (SP) region centered around (60 S, 110 degrees W). The intensively reported Weddell Sea Anomaly falls inside the SP region. The phase reversal occurs during March-August in EA and NA regions, and between August and March in SP region, being most prominent in local summer. Furthermore, this diurnal anomaly is more pronounced at solar minimum than at solar maximum, and more pronounced in SP region than in NA and EA regions, in terms of larger diurnal magnitude and more months it lasts in a year. It is emphasized that the diurnal anomaly consists of not only a nighttime enhancement, but also a concurrent noontime depletion. Hence, midlatitude summer nighttime enhancements reported in previous studies are just part of this reversed diurnal cycle. The cause for the phase reversal involves several interplaying physical processes. Among these, the neutral wind combined with the geomagnetic field configuration plays a pivotal role. It generates a one-wave longitudinal pattern at southern middle latitudes and a two-wave pattern at northern middle latitudes, whose wave peaks correspond to the center of the SP, EA, and NA regions, respectively. The seasonal variation of neutral winds and downward motion of the ionization induced by thermal contraction of the ionosphere at sunset may largely control the occurring local time of the nighttime density enhancement and how long it persists in different months. The phase reversal occurs as a result of close ion-neutral coupling. It is further noted that winter anomaly in the EA, NA, and SP regions is very weak or missing.

    DOI： 10.1029/2009JA014689

  • First tomographic observations of the Midlatitude Summer Nighttime Anomaly over Japan Reviewed

    Smitha V. Thampi, Charles Lin, Huixin Liu, Mamoru Yamamoto

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   114   2009.10

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    Recently, a chain of digital beacon receivers has been established over Japan, mainly for the tomographic imaging of the ionosphere. These receivers are installed at Shionomisaki (33.45 degrees N, 135.8 degrees E), Shigaraki (34.85 degrees N, 136.1 degrees E), and Fukui (36.06 degrees N, 136 degrees E), which continuously track the Low Earth Orbiting Satellites (LEOS), and the simultaneous line-of-sight Total Electron Content (TEC) data are used for tomographic reconstruction. In the images obtained during July 2008, it is seen that the nighttime electron densities exceed the daytime values on almost all days over latitudes > 33-34 degrees N. On several days, these northern latitudes show enhanced electron densities compared to the low-latitude region during nighttime. These are the prominent features of the "Midlatitude Summer Nighttime Anomaly (MSNA)'' that is recently observed in the northern hemisphere and is considered similar to the nighttime Weddell Sea Anomaly (WSA). This is the first study of the MSNA using tomographic technique and found its significant day-to-day variability. The ionosonde data from Wakkanai (45.4 degrees N, 141.7 degrees E), ground-based GPS TEC observations using the GEONET, CHAMP in situ electron density measurements, and Formosat3/COSMIC (F3/C) occultation measurements are also used to confirm the presence of MSNA over this region and to examine its variability. It is seen that, in general, during the local summer period, electron density over the northern latitudes is highest at similar to 2000-2100 LT and the latitudinal enhancement in electron density also begins to appear around the same time, which continues to exist even at later hours.

    DOI： 10.1029/2009JA014439

  • Seasonal variation of the longitudinal structure of the equatorial ionosphere: Does it reflect tidal influences from below? Reviewed

    Huixin Liu, Shigeto Watanabe

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   113 ( A8 )   2008.8

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    We have examined the longitudinal structure of the equatorial ionosphere at 400-km altitude in the noon and postsunset local time sectors in different seasons using 6 years of F-region plasma density observations from the CHAMP satellite. A four-peak wave structure is observed in both local time sectors. In the noon sector at a fixed solar flux level, this structure is observed to be most prominent around September equinox and weakest around December solstice. This seasonal dependence agrees well with that of the nonmigrating diurnal tides DE3, hence supporting a close coupling between the ionosphere and the mesosphere-lower thermosphere possibly via the DE3 tidal modulation of the E-layer dynamo. In the postsunset sector, however, such agreement cannot be claimed. In this sector, although the four-peak structure can be observed in all seasons at moderate and high solar flux levels, its seasonal dependence does not follow that of the DE3 tides. This structure becomes indiscernible near solstices at low solar flux levels. Furthermore, the postsunset four-peak wave structure exhibits larger amplitude than that during daytime, hence indicating that it is more likely an amplified feature rather than a remnant of the daytime structure. The prereversal enhancement is speculated to be a possible candidate to cause this amplification.

    DOI： 10.1029/2008JA013027

  • Solar activity dependence of the electron density in the equatorial anomaly regions observed by CHAMP Reviewed

    Huixin Liu, Claudia Stolle, Matthias Foerster, Shigeto Watanabe

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   112 ( A11 )   2007.11

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    We have investigated the solar activity dependence of the electron density at equatorial and low latitudes using 6 years ( a) of measurements between 1 August 2000 and 1 August 2006 from CHAMP and compared it with the international reference ionosphere ( IRI) model. The solar activity dependence observed by CHAMP at 400 km altitude exhibits significant variation with latitude, season, and local time. First, the electron density in the crest regions of the equatorial ionization anomaly ( EIA) grows roughly linearly from solar minimum to solar maximum, with a higher growth rate than that in the EIA trough region. Second, the solar activity dependence in the EIA crest regions varies strongly with season. The growth rate of the electron density with increasing solar activity around equinoxes is about 1.5 to 2 times greater than that near solstices. Third, the solar activity dependence of the EIA structure varies significantly with local time. In the noon sector the crest-to-trough ratio ( CTR) obtained at 400 km altitude varies within only a small range between 1.14 and 1.43 from solar minimum to solar maximum. In the postsunset local time sector, however, the CTR grows remarkably with solar activity level, reaching values of above 3.9 at solar maximum. These differences are attributed to the different solar activity dependence of the vertical plasma drift in corresponding local time sectors. The IRI model was found to reproduce the equatorial electron density well near 400 km in the noon sector at all solar activity levels. However, it significantly overestimates it in the postsunset to premidnight sector at high solar activity levels. The major cause for this overestimation has been found to be the IRI's inadequate representation of the F-2 layer maximum height ( h(m)F(2)) in this sector, while the IRI's lack of equatorial spread F seems to play only a minor role.

    DOI： 10.1029/2007JA012616

  • Contrasting behavior of the thermosphere and ionosphere in response to the 28 October 2003 solar flare Reviewed

    Huixin Liu, Hermann Luehr, Shigeto Watanabe, Wolfgang Koehler, C. Manoj

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   112 ( A7 )   2007.7

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    [1] We examined the thermospheric and ionospheric responses to the solar flare on 28 October 2003, utilizing simultaneous observations of the electron and neutral density from the CHAMP satellite. Rapid thermospheric response within a few minutes was observed. In addition, the neutral and plasma perturbations contrasted each other remarkably. First, their temporal development differed. Though started nearly simultaneously, the plasma perturbation developed much faster and to a larger amplitude than its neutral counterpart. Second, their latitudinal distributions differed. At the initial stage of the response, the neutral density was enhanced by 20% almost homogeneously at all latitudes below 50 degrees N/S. In comparison, the plasma disturbance exhibited a distinctive latitudinal structure, with largest density enhancements of 68% at the dip equator, moderate increase of similar to 20% at midlatitudes, and depression up to 35% around 15 degrees N/S. This suggests a decoupling between the neutral and plasma disturbances during this stage. The plasma-neutral coupling via ion drag was found to become important about 2 - 3 hours after the flare bursts. Another interesting feature is that the equatorial ionization anomaly was significantly weakened during the flare. The observations demonstrated that electrodynamics related to the equatorial fountain dominated the photochemistry in controlling the flare-induced plasma density disturbances on 28 October 2003. This differs considerably from the nearly linear cos(SZA) dependence of flare-induced total electron content enhancements.

    DOI： 10.1029/2007JA012313

  • Climatology of the equatorial thermospheric mass density anomaly Reviewed

    Huixin Liu, Hermann Luehr, Shigeto Watanabe

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   112 ( A5 )   2007.5

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    The equatorial anomaly is an interesting and important feature of the Earth's thermosphere-ionosphere coupling in tropical regions. It is an anomalous latitudinal distribution found in both the ionized and unionized part of the atmosphere. Its equinox configuration consists of a minimum near the dip equator flanked by two maxima on both sides. The ionospheric side of this anomaly, often referred to as the equatorial ionization anomaly ( EIA), has long been recognized since the 1930s. However, its thermospheric counterpart was only to be glimpsed by the Dynamic Explorer 2 satellite in the 1970s. A global picture of it has been rather recently revealed by the CHAMP satellite in 2005. In this paper we complement previous studies by investigating the climatology of the equatorial mass anomaly ( EMA) in the thermosphere using 4 years of CHAMP measurements. Our analysis has revealed strong variation of the EMA with season and solar flux level. The EMA structure is most prominent around equinox, with a crest-to-trough ratio about 1.05 for F10.7 = 150. Near solstices, it is asymmetric about the dip equator. The density crest attains maximum 1-2 hours earlier and reaches higher values in the summer hemisphere than in the winter hemisphere. The density in EMA regions varies semiannually, with maxima near equinoxes. The latitudinal locations of the EMA crests undergo a seasonal variation, obviously following the movement of the subsolar point. The EMA structure has also been found to become more pronounced at higher solar flux levels. Both the location and magnitude of the EMA crests closely follow those of the EIA in corresponding seasons and solar flux levels, hence demonstrating strong plasma-neutral interaction. Furthermore, two seasonal asymmetries clearly present in the globally averaged density, with the density in March/December being similar to 15-20% higher than that in September/June.

    DOI： 10.1029/2006JA012199

  • 極域電離圏上部におけるイオン上昇流の観測

    佐藤 創我, Liu Huixin, 渡部 重十

    北海道大学地球物理学研究報告   ( 70 )   13 - 25   2007.3

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    Ion upflow observed in the polar ionospbere

    DOI： 10.14943/gbhu.70.13

  • Zonal winds in the equatorial upper thermosphere: Decomposing the solar flux, geomagnetic activity, and seasonal dependencies Reviewed

    Huixin Liu, Hermann Luehr, Shigeto Watanabe, Wolfgang Koehler, Vance Henize, Pieter Visser

    JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   111 ( A7 )   2006.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    [ 1] Using 3 years ( 2002 - 2004), over 16,400 orbits of measurements from the accelerometer on board the CHAMP satellite, we have studied the climatology of the equatorial zonal wind in the upper thermosphere. Several main features are noticed. The most prominent one is that the solar flux significantly influences both the daytime and nighttime winds. It overrides the geomagnetic activity effect, which is found to be rather limited to the nightside. An elevation of the solar flux level from F10.7 approximate to 100 x 10(-22) W m(-2) Hz(-1) to F10.7 approximate to 190 x 10(-22) Wm(-2) Hz(-1) produces an eastward disturbance wind up to similar to 110 m s(-1). This consequently enhances the nighttime eastward wind but suppresses the daytime westward wind. A seasonal variation with weaker wind ( by over 50 m s(-1) at night) around June solstice than in other seasons has been observed regardless of solar flux and geomagnetic activity levels. The zonal wind is eastward throughout the night except around June solstice, where it ebbs to almost zero or turns even westward in the postmidnight sector at low solar flux level. The daytime wind is found to be generally more stable than the nighttime wind, particularly unresponsive to geomagnetic activities. Predictions from the Horizontal Wind Model find good agreement with the CHAMP-observed wind at high solar flux levels during nighttime. At low solar flux levels, however, the model strongly underestimates the westward wind during morning hours by 50 - 120 m s(-1) depending on season. The major difference between the HWM-predicted and the CHAMP-observed wind is seen in the phase of its diurnal variation. The CHAMP-observed wind turns eastward around 1200 - 1300 MLT instead of 1600 - 1700 MLT predicted by the model. Comparisons with ground FPI observations and the NCAR Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIEGCM) predictions show that the solar flux effect obtained from CHAMP is consistent with that modeled by TIEGCM. The solar flux dependence of zonal wind found here together with that of the zonal ion drift found in previous studies reflect the relative importance of the E- and F-region wind dynamo in the thermosphere-ionosphere coupling process. Furthermore, these wind measurements indicate that the Earth's atmosphere superrotates. The average superrotation speed amounts to about 22 m s(-1) for a solar flux level of F10.7 approximate to 100 x 10(-22) W m(-2) Hz(-1) but increases to 63 m s(-1) for F10.7 approximate to 190 x 10(-22) W m(-2) Hz(-1). Finally, the wind behavior presented in this study is longitudinally averaged and may differ from wind measurements at a certain longitude.

    DOI： 10.1029/2005JA011415

  • A comparative study of magnetic storm effects on the ionosphere in the polar cap and auroal oval - F-region negative storm Reviewed

    SY Ma, HX Liu, K Schlegel

    CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION   45 ( 2 )   160 - 169   2002.3

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    Language：Others   Publishing type：Research paper (scientific journal)  

    With coordinated EISCAT and ESR radar data, ionospheric storm in both the dayside polar cap and the auroral oval during the major magnetic storm of May 15, 1997 is studied, focusing on the F-region negative storm. It is found that in both the polar cap and the auroral zone a F1-like peak of ionization appeared at 190km height during the main and recovery phases of the storm; while the normal F2 peak disappeared and great depletions of electron density occurred. In contrast, variations of ion temperature are very different in the two regions, with little change in polar cap while strong enhancement in auroral oval, implying a difference in key mechanisms for the negative storms in the two regions. The increase of O+ ion loss rate through chemical reaction due to Joule heating and enhancement of ion temperature resulted from strong electric field played a crucial role in the auroral zone. The plasma transport process, however, especially the long-lasting large ion upflow, is of great importance-in the polar cap. In addition, large F-region electron density depletion associated with null Joule heating and ion temperature enhancement is observed by EISCAT radar in the transient region of the two cells of plasma convection, which is caused by strong field-aligned O+ ion outflow when the radar passing through probably under the polar cleft ion fountain region.

  • A reversed plasma convection flow in the polar ionosphere observed with EISCAT radar Reviewed

    SY Ma, P Liu, HX Liu, K Schlegel, JS Xu

    CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION   44 ( 4 )   446 - 453   2001.7

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    Language：Others   Publishing type：Research paper (scientific journal)  

    An abnormal anti-sunward intense flow of plasma convection is observed by EISCAT radar in the high-latitude ionosphere near the polar cap boundary. It occurred at morning sector of MLT under conditions of southward IMF B-z during the recovery phase of a moderate magnetic storm. A synthetic analysis of radar data and in-situ satellite observations is made in combination with a tracing of magnetic field lines by means of magnetospheric field model on this event. It is evidently indicated that the abnormal reversed westward flow of plasma convection and the features of the plasma structure and property are probably the ionospheric signatures of magnetic reconnection taking place at the dayside magnetopause.

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Books

  • Cross-scale coupling and energy transfer in the magnetosphere-ionosphere-thermosphere system, Chapter 7, Thermosphere-Ionosphere Interaction,

    @Huixin Liu, S. England（Role：Joint author）

    Elsevier  2022.5 

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    Responsible for pages：ISBN: 978-0-12-821366-7   Language：English   Book type：Scholarly book

    DOI： ISBN:978-0-12-821366-7

  • Space Physics and Aeronomy Collection Volume 3: Ionosphere dynamics and application, Chapter 16: Sudden stratospheric warming impacts on the ionosphere-thermosphere system – A review of recent progress

    Goncharenko, L., V. L. Harvey, @Huixin Liu, N. Pedatella（Role：Joint author）

    Americal Geophysical Union  2021.5 

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    Responsible for pages：ISBN: 13978-1-119-50755-0   Language：English   Book type：Scholarly book

    DOI： ISBN:13978-1-119-50755-0

  • Space Physics and Aeronomy Collection Volume 4, Upper Atmosphere Dynamics and Energetics, Chapter 15:Day-to-day variability of the thermosphere and ionosphere

    @Huixin Liu, Y. Yamazaki, J. Lei（Role：Joint author）

    Americal Geophysical Union  2021.5 

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    Responsible for pages：ISBN: 978-1-11950-756-7   Language：English   Book type：Scholarly book

    DOI： ISBN:978-1-11950-756-7

  • Modeling the Ionosphere-Thermosphere System: Chapter 21:Low-latitude ionosphere and thermosphere: decadal observations from the CHAMP mission

    Claudia Stolle, Huixin Liu（Role：Joint author）

    Americal Geophysical Union  2014.8 

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    Language：English   Book type：Scholarly book

    DOI： doi:10.1002/9781118704417.ch21

  • Aeronomy of the Earth's Atmosphere and Ionosphere: New aspects of the coupling between thermosphere and ionosphere, with special regards to CHAMP mission results

    Hermann Lühr, Huixin Liu, Jeahueng Park, and Sevim Müller（Role：Joint author）

    Springer  2011.8 

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    Responsible for pages：303-316   Language：English   Book type：Scholarly book

  • Earth Observation with CHAMP

    Huixin Liu, Hermann Lühr, W. Koehler（Role：Joint author）

    Springer, Berlin  2004.12 

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    Language：English   Book type：Scholarly book

  • Cross-scale coupling and energy transfer in the magnetosphere-ionosphere-thermosphere system

    Huixin Liu, Scott England（Role：ContributorLarge-scale structures and ion-neutral coupling）

    Elsevier  2022    （ ISBN:9780128213667 ）

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    Total pages：xiv, 549 p.   Language：English  

    CiNii Books

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Presentations

  • Impact of ENSO on MLT tides Invited International conference

    Huixin Liu

    CEDAR  2023.6 

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    Event date： 2023.6

    Language：Others   Presentation type：Oral presentation (general)  

    Country：Other  

    DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation

  • DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation International conference

    Huixin Liu

    JpGU  2023.5 

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    Event date： 2023.5

    Language：Others  

    Country：Other  

    DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation

  • Impact of El Nino-induced O3 variability on MLT tides International conference

    Huixin Liu

    JpGU  2023.5 

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    Event date： 2023.5

    Language：Others  

    Country：Other  

    DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation

  • Atmosphere-Ionosphere Coupling and Its role in Space Weather Invited International conference

    Huixin Liu

    8th IAGA/ICMA/SCOSTEP workshop on vertical coupling in the atmosphere-ionosphere system  2022.7 

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    Event date： 2022.7

    Language：English  

    Country：Other  

    Atmosphere-Ionosphere Coupling and Its role in Space Weather

  • DW1 enhancement in MLT during 2015 El Niño Invited International conference

    Huixin Liu

    15TH QUADRENNIAL SOLAR-TERRESTRIAL PHYSICS SYMPOSIUM (STP-15)  2022.2 

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    Event date： 2022.2

    Language：English  

    Country：Other  

    DW1 enhancement in MLT during 2015 El Niño

  • How does geomagnetic activity affect the CO2-driven trend in the thermosphere and ionosphere Invited International conference

    @Huixin Liu

    IAGA-IAMAS joint meeting  2021.8 

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    Event date： 2021.8

    Language：English   Presentation type：Oral presentation (general)  

    Country：Other  

    How does geomagnetic activity affect the CO2-driven trend in the thermosphere and ionosphere

  • How does geomagnetic activity affect the CO2-driven trend in the thermosphere and ionosphere Invited International conference

    Huixin Liu

    国際地磁気学・国際地震学連合学会(IAGA-IASPEI)  2021.8 

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    Event date： 2021.8

    Language：English  

    Country：Other  

    How does geomagnetic activity affect the CO2-driven trend in the thermosphere and ionosphere

  • The atmosphere-ionosphere coupling and space weather Invited International conference

    @Huixin　Liu

    ドイツDFG基金会特別推進プログラムSPPシンポジウム  2021.6 

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    Event date： 2021.5 - 2021.6

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Online   Country：Germany  

  • Gravity wave weakening during the 2019 Antarctic stratospheric sudden warming Invited International conference

    @M. Kogure @Huixin　Liu

    JpGU 2021  2021.5 

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    Event date： 2021.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Austria  

  • Geomagnetic activity effects on CO2-driven trend in the ionosphere: GAIA experiments Invited International conference

    @Huixin　Liu

    European Geophysical Union 2021  2021.4 

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    Event date： 2021.4

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Austria  

  • Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2 doubling Invited International conference

    @Liu Huixin, @C. Tao, @H. Jin

    COSPAR  2021.1 

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    Event date： 2021.1 - 2021.2

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Australia  

  • 空に見えない「電離圏」と言うものがある Invited

    @Liu Huixin

    SGEPSS2020　（日本電磁気・惑星学会）  2020.11 

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    Event date： 2020.11

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Venue：Online   Country：Japan  

  • AGU FAIR data policy and author guideline Invited

    @Liu Huixin

    SGEPSS2020　（日本電磁気・惑星学会）  2020.11 

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    Event date： 2020.11

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Japan  

  • Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2 doubling International conference

    @Liu Huixin, @C. Tao, @H. Jin

    中間圏・熱圏・電離圏研究集会２０20  2020.9 

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    Event date： 2020.9

    Language：Japanese   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Japan  

  • Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2 doubling International conference

    @Liu Huixin, @C. Tao, @H. Jin

    JpGU２０20  2020.7 

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    Event date： 2020.7

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Japan  

    Thermosphere cooling is a known effect of increasing CO2 in the atmosphere. In this study, we explore the changes of thermosphere circulation and tides in the cooled thermosphere via a doubled CO2 numerical experiment using the Ground-to-topside Atmosphere Ionosphere model for Aeronomy (GAIA). The results reveal three major features. (1) The thermosphere cools about 10 K more around solstices than equinoxes, more at the summer pole than the winter pole. (2) The meridional circulation shifts downward and strongly accelerates by 5–15 m s−1. (3) The tidal activity experiences dramatic changes, with a 40–60% reduction in the semidiurnal tides (SW2) throughout the thermosphere but an 30–50% enhancement in diurnal tides (DW1) below 200 km altitude. The nonmigrating tide DE3 has only minor changes. These changes in temperature, meridional circulation, and tides are persistent features in all seasons and can profoundly affect the spatial distribution and diurnal cycles of the ionospheric responses to CO2 doubling via atmosphere composition and electrodynamics

  • The Earth's upper atmosphere and space weather Invited International conference

    @Huixin　Liu

    JpGU２０20  2020.7 

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    Event date： 2020.7

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Online   Country：Japan  

    地球の電離圏と宇宙天気の最先端の研究結果を多分野の研究者をわかりやすく解説する。

  • Dynamical response of the upper atmosphere to CO2 doubling: GAIA simulation International conference

    @Huixin Liu, C. Tao., H. Jin, #T. Abe

    AGU2019  2019.12 

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    Event date： 2019.12

    Language：English   Presentation type：Oral presentation (general)  

    Venue：San Francisco   Country：United States  

  • Vertical structure of terdiurnal tides in the Antarctic MLT region: 15-year observation over Syowa (69S, 39E) International conference

    @Huixin Liu, M. Tsutsumi, H. Liu

    SGEPSS2019  2019.10 

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    Event date： 2019.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Kumamoto   Country：Japan  

  • Vertical structure of terdiurnal tides in the Antarctic MLT region: 15-year observation over Syowa (69S, 39E) Invited International conference

    @Huixin Liu, M. Tsutsumi, H. Liu

    IUGG2019  2019.7 

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    Event date： 2019.7

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Montreal   Country：Canada  

  • ENSO effects on MLT diurnal tides: a 21-year reanalysis-drive GAIA model simulation International conference

    @Liu Huixin, @Y. Sun, @Y. Miyoshi, @H. Jin

    JpGU２０１９  2019.5 

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    Event date： 2019.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Chiba   Country：Japan  

  • ENSO effects on MLT diurnal tides: a 21-year reanalysis-drive GAIA model simulation International conference

    @Liu Huixin, @Y. Sun, @Y. Miyoshi, @H. Jin

    AOGS2018  2018.6 

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    Event date： 2018.6

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Honolulu   Country：United States  

  • Medium-scale GW activity in bottomside F region (GPS 通信障害の原因となるプラズマバブルの発生源に迫る) International conference

    @Liu Huixin

    JpGU meeting 2018, international session  2018.5 

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    Event date： 2018.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

    Thermospheric gravity waves (GWs) in the bottomside F region have been proposed to play
    a key role in the generation of equatorial plasma bubbles (EPBs). However, direct observations of such waves are scarce. This study provides a systematic survey of medium-scale (<620 km) neutral atmosphere perturbations at this critical altitude in the tropics, using 4 years of in situ Gravity Field and Steady-State Ocean Circulation Explorer satellite measurements of thermospheric density and zonal wind. The analysis reveals pronounced features on their global distribution and seasonal variability: (1) A prominent three-peak longitudinal structure exists in all seasons, with stronger perturbations over continents than over oceans. (2) Their seasonal variation consists of a primary semiannual oscillations (SAO) and a secondary annual oscillation (AO). The SAO component maximizes around solstices and minimizes around equinoxes,
    while the AO component maximizes around June solstice. These GW features resemble those of EPBs
    in spatial distribution but show opposite trend in climatological variations. This may imply that stronger medium-scale GW activity does not always lead to more EPBs. Possible origins of the bottomside GWs are discussed, among which tropical deep convection appears to be most plausible.

  • Thermosphere response to CO2 doubling: GAIA simulation results International conference

    Liu Huixin, Y. Nakamoto, Y. Miyoshi

    10th international workshop on Long-term trends  2018.5 

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    Event date： 2018.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Hefei   Country：China  

  • Role of Medium-scale GW in seeding plasma bubbles

    @Liu Huixin

    NIPR symposium 2017  2017.12 

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    Event date： 2017.12

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Tokyo   Country：Japan  

  • Medium-scale GW activity in bottomside F region

    @Liu Huixin

    SGEPSS 2017  2017.10 

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    Event date： 2017.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Kyoto   Country：Japan  

  • Thermosphere response to CO2 doubling: GAIA simulation results Invited International conference

    Liu Huixin, Y. Nakamoto, Y. Miyoshi

    AOGS2017  2017.8 

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    Event date： 2017.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • ENSO effects on MLT diurnal tides: a 21-year reanalysis-drive GAIA model simulation International conference

    @Liu Huixin, @Y. Sun, @Y. Miyoshi, @H. Jin

    AGU-JpGU joint meeting 2017  2017.5 

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    Event date： 2017.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Thermosphere interannual variability: potential fingerprints of QBO and ENSO Invited

    Liu Huixin

    JAXA symposium  2016.12 

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    Event date： 2016.12 - 2015.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：JAXA   Country：Japan  

    Interannual variation of the upper atmosphere

  • Thermosphere interannual variability: implications for ENSO and QBO Invited

    Liu Huixin

    The International Whole Atmospherear Symposium  2016.9 

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    Event date： 2016.9

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Tokyo   Country：Japan  

  • Thermosphere interannual variability: ENSO effects Invited

    Liu Huixin

    Mesosphere-Thermosphere-ionosphere workshop  2016.8 

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    Event date： 2016.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Tokyo   Country：Japan  

  • Thermosphere and Ionosphere response to solar flares Invited International conference

    Liu Huixin

    VarSITI/ SCOSTEP symposium  2016.6 

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    Event date： 2016.6

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Varna   Country：Bulgaria  

    This invited talk summarize the thermosphere and ionosphere response to solar flares, and emphasize recent progresses made by satellite observations.

  • Thermosphere response to stratosphere sudden warming simulated by GAIA Invited International conference

    Liu Huixin

    ISEA2015  2015.10 

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    Event date： 2015.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Bahir Dar   Country：Ethiopia  

  • Earthquake Ionosphere Precursor Study Group and Its Role - Toward Strengthening Earthquake Study International conference

    K. Oyama, K. Ryu, Liu Huixin

    AOGS2015  2015.8 

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    Event date： 2015.8 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Structure and Origins of the Weddell Sea Anomaly From Tidal and Planetary Wave Signatures in FORMOSAT-3/COSMIC Observations and GAIA GCM Simulations International conference

    L. Chang, Liu Huixin, Yasunobu Miyoshi

    AOGS2015  2015.8 

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    Event date： 2015.8 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Contribution of the Mid-Latitude Seismic Activity to the EIA Intensity Variation Suggested by Satellite Electron Density Measurements International conference

    K. Ryu, K. Oyama, Liu Huixin

    AOGS2015  2015.8 

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    Event date： 2015.8 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Diversity of Ionosphere Modification Possibly Caused by Large Earthquakes International conference

    K. Oyama, K. Ryu, Liu Huixin

    AOGS2015  2015.8 

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    Event date： 2015.8 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • EEJ Empirical Model Based on Ground-Based Magnetometer Data International conference

    N. S. A. Hamid, Liu Huixin

    AOGS2015  2015.8 

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    Event date： 2015.8 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Periodic Variations in the Thermospheric Density International conference

    Liu Huixin

    AOGS2015  2015.8 

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    Event date： 2015.8 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Thermosphere responses to SSWs simulated by GAIA model Invited International conference

    Liu Huixin

    CEDAR 2015  2015.6 

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    Event date： 2015.6 - 2014.6

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Seattle   Country：United States  

  • Variability of the Equatorial Ionization Anomaly on seasonal and day to day time scales International conference

    CHIEN, Shin han, CHANG, Loren, Liu Huixin

    JpGU meeting 2015, international session  2015.5 

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    Event date： 2015.5 - 2014.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Periodic variations in the thermospheric density International conference

    Liu Huixin

    JpGU meeting 2015, international session  2015.5 

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    Event date： 2015.5 - 2014.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Upper atmosphere response to stratosphere sudden warming events Invited International conference

    Liu Huixin

    SCOSTEP  2014.10 

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    Event date： 2014.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Xi'an   Country：China  

  • Thermal and dynamical response of the thermosphere to stratosphere sudden warming Invited International conference

    Liu Huixin

    SCOSTEP 2014  2014.10 

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    Event date： 2014.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Xian   Country：China  

  • Current Status of the MAGDAS Project - The Largest Magnetometer Array in the World International conference

    G. Maeda, Kiyohumi Yumoto, Liu Huixin

    AOGS2014  2014.8 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • The Ionospheric Sq Current Systems Influenced by Semidiurnal Tide During Sudden Stratospheric Warming Events Simulated by the Kyushu-GCM International conference

    Rinako TAKAZAKI, Liu Huixin, Saburo Miyahara

    AOGS2014  2014.7 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • Thermosphere Cooling at Low and Middle Latitudes During Stratosphere Warming Events: GAIA Model Simulations International conference

    Liu Huixin

    AOGS2014  2014.7 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • Ionospheric Response to 2009 Sudden Stratosphere Warming in the Northern and Southern Hemisphere International conference

    J. Jhou, Y. Oyama, C. Lin, Liu Huixin

    AOGS2014  2014.7 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Local Time and Longitudinal Dependence of Equatorial Electrojet Calculated from Ground-based Magnetometer International conference

    N. S. A. Hamid, Liu Huixin

    AOGS2014  2014.7 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Coordinated Measurements of Medium-scale Traveling Ionospheric Disturbances with Ground-based Airglow Imagers and CHAMP Satellite International conference

    Shin Suzuki, J. Park, Y. Otsuka, Liu Huixin, H. Luehr

    AOGS2014  2014.7 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • Solar Activity and Seasonal Effects of the Upper Atmosphere at High Latitudes According to Observations and Modelling International conference

    M. Förster, Liu Huixin, C. Stolle

    AOGS2014  2014.7 

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    Event date： 2014.7 - 2014.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

  • MLT and seasonal dependence of auroral electrojets: IMAGE magnetometer network observations International conference

    Guo Jianpeng, Liu Huixin

    JpGU meeting 2014, international session  2014.5 

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    Event date： 2014.4 - 2014.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Yokohama   Country：Japan  

  • Enhancing our understanding of the atmosphere-ionosphere coupling with Low Earth Orbiting satellite missions International conference

    Liu Huixin, Hermann Luehr

    JpGU meeting 2014, international session  2014.4 

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    Event date： 2014.4 - 2014.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Yokohama   Country：Japan  

  • CAHMP 衛星の磁場データを用 いた中低緯度電離層電流の再構築

    Liu Huixin, Deguchi Ryo

    地球電磁気・地球惑星圏学会(SGEPSS)  2013.11 

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    Event date： 2013.11

    Language：Japanese   Presentation type：Oral presentation (general)  

    Venue：高知   Country：Japan  

  • 熱圏の密度の季節変化

    Liu Huixin, Tsubosaki Hiroyuki

    地球電磁気・地球惑星圏学会(SGEPSS)  2013.11 

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    Event date： 2013.11

    Language：Japanese   Presentation type：Oral presentation (general)  

    Venue：高知   Country：Japan  

  • vertical coupling processes in the Earth's system Invited International conference

    Liu Huixin

    NASA review panel  2013.8 

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    Event date： 2013.8

    Language：English   Presentation type：Symposium, workshop panel (public)  

    Venue：NASA 本部   Country：United States  

  • Global mean cooling of the thermosphere during the 2009 major SSW International conference

    Liu Huixin

    Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium  2013.11 

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    Event date： 2013.7 - 2013.11

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Nagoya, Japan   Country：Japan  

  • The equatorial electrojet and global Sq current components at dip equator International conference

    Liu Huixin, Nurul Shazana Abdul Hamid

    Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium  2013.11 

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    Event date： 2013.7 - 2013.11

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Nagoya, Japan   Country：Japan  

  • Ionospheric current system derived from CHAMP using DECS method at low and middle latitudes International conference

    Liu Huixin, Deguchi Ryo

    Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium  2013.11 

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    Event date： 2013.7 - 2013.11

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Nagoya, Japan   Country：Japan  

  • Thermosphere response to lower atmosphere forcing: decadal observations from the CHAMP mission Invited International conference

    Liu Huixin

    Workshop  on  Whole  Atmosphere   Coupling  During  Solar  Cycle  24  2013.7 

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    Event date： 2013.7

    Language：English   Presentation type：Oral presentation (general)  

    Venue：National Central University, Taiwan   Country：Taiwan, Province of China  

  • Brief Study of Equatorial Electrojet and Global Sq Currents At Southeast Asia Region International conference

    Nurul  Shazana  Abdul  Hamid, Liu Huixin

    IEEE International Conference on Space Science and Communication (IconSpace)  2013.7 

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    Event date： 2013.7

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Melaka   Country：Malaysia  

  • Relation Between the Local Equatorial Electrojet and Global Sq Current Calculated from Different Longitude Sectors International conference

    N. A. A. Hamid, Liu Huixin, Kiyohumi Yumoto

    AOGS2013  2013.6 

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    Event date： 2013.6

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Brisbane   Country：Australia  

  • Relation Between the Local Equatorial Electrojet and Global Sq Current Calculated from Different Longitude Sectors International conference

    Nurul  Shazana  Abdul  Hamid, Liu Huixin

    Asia Oceania Geosciences Society  2013.6 

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    Event date： 2013.6

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Brisbane   Country：Australia  

  • Investigation on the Possible Relationship between Magnetic Pulsations and Earthquakes International conference

    Jusoh Mohamad Huzaimy, Liu Huixin, Yumoto Kiyohumi

    AGU fall meeting 2012  2012.12 

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    Event date： 2012.12

    Language：English   Presentation type：Oral presentation (general)  

    Venue：San Francisco   Country：United States  

  • Upper thermosphere coupling with the lower atmosphere: the known and unknown

    Liu Huixin

    地球電磁気・地球惑星圏学会  2012.11 

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    Event date： 2012.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • 1D simulation of Electron acceleration by Inertial Alfven wave pulse

    Shi Run, Liu Huixin, Yoshikawa Akimasa

    地球電磁気・地球惑星圏学会  2012.11 

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    Event date： 2012.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • Exploration of the Possible Relationship between Magnetic Pulsations and Earthquakes

    Jusoh Mohamad Huzaimy, Liu Huixin, Yumoto Kiyohumi

    地球電磁気・地球惑星圏学会  2012.11 

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    Event date： 2012.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • GAIA model simulation of the thermosphere response to SSW

    Liu Huixin, Jin, H, Miyoshi Yasunobu, Fujiwara Hitoshi, Shinagawa, H.

    地球電磁気・地球惑星圏学会  2012.11 

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    Event date： 2012.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • Relation between the local equatorial electrojet and global Sq current system

    ABDUL HAMID NURUL SHAZANA, Liu Huixin

    地球電磁気・地球惑星圏学会  2012.11 

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    Event date： 2012.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • Variation of the equatorial electrojet and the global Sq driven by solar radiation

    Z. Shazana, Huixin Liu

    MTI workshop  2012.8 

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    Event date： 2012.8

    Presentation type：Oral presentation (general)  

    Venue：Tokyo   Country：Japan  

  • Upper atmosphere response to stratosphere sudden warming: local time and height dependence simulated by GAIA model International conference

    Liu Huixin

    JpGU meeting 2013, international session  2013.5 

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    Event date： 2012.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Modification of one-dimensional spherical elementary current systems for applying at low/mid latitude International conference

    Deguchi Ryo, Liu Huixin

    JpGU meeting 2013, international session  2013.5 

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    Event date： 2012.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Relation between the local equatorial electrojet and global Sq current calculated from different longitude sectors International conference

    Nurul Shazana Abdul Hamid, Liu Huixin

    JpGU meeting 2013, international session  2013.5 

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    Event date： 2012.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Possible relationship between Solar Wind Input Energy and Seismicity International conference

    Liu Huixin, Mohamad Huzaimy Bin Jusoh

    JpGU meeting 2013, international session  2013.5 

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    Event date： 2012.5

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Upper atmosphere response to major and minor stratosphere sudden warming Invited International conference

    Liu Huixin

    ISEA13  2012.3 

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    Event date： 2012.3

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Paracas   Country：Peru  

  • Upper atmosphere response to stratosphere sudden warming International conference

    Huixin Liu

    SSW workshop 2012  2012.2 

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    Event date： 2012.2

    Presentation type：Oral presentation (general)  

    Venue：Kyoto   Country：Japan  

  • Solar activity dependence of the thermosphere and ionosphere: contribution from 10 years of CHAMP observations Invited International conference

    Huixin Liu

    AGU  2011.12 

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    Event date： 2011.12

    Presentation type：Oral presentation (general)  

    Venue：San Francisco   Country：United States  

  • Ionosphere and thermosphere response to stratosphere sudden warming

    Huixin Liu

    SGEPSS fall meeting  2011.11 

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    Event date： 2011.11

    Presentation type：Oral presentation (general)  

    Venue：Kobe   Country：Japan  

  • Equatorial electrodynamics and neutral background in the Asian sector during the 2009 Stratosphere sudden warming Invited International conference

    Liu Huixin

    AOGS  2011.8 

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    Event date： 2011.8

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Taipei   Country：Taiwan, Province of China  

  • Upper-lower atmosphere coupling: known and unknowns Invited International conference

    Liu Huixin

    IUGG 2011 General Assembly  2011.7 

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    Event date： 2011.6 - 2011.7

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Melbourne   Country：Australia  

  • Faster circulation in a cooler upper atmosphere: GAIA simulation with doubled CO2 Invited

    Huixin Liu

    COSPAR  2021.1 

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    Language：English  

    Country：Other  

    Faster circulation in a cooler upper atmosphere: GAIA simulation with doubled CO2

  • DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation Invited International conference

    @Huixin Liu

    STP-15  2022.2 

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    Language：English   Presentation type：Oral presentation (general)  

    Venue：Online   Country：Other  

    DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation

  • Response of thermosphere and ionosphere to increasing CO2 International conference

    Huixin Liu

    International symposium for Equatorial Aeronomy  2022.9 

    　More details

    Language：Others  

    Country：Other  

    Response of thermosphere and ionosphere to increasing CO2

  • Response of thermosphere and ionosphere to increasing CO2 Invited International conference

    Huixin LIU

    NASA Goddard Special Seminar  2023.3 

    　More details

    Language：Others  

    Country：United States  

    Response of thermosphere and ionosphere to increasing CO2

  • Atmosphere-Ionosphere Coupling & its Role in Space Weather Invited International conference

    Huixin LIU

    SCOSTEP PRESTO symposium  2023.6 

    　More details

    Language：English  

    Country：Italy  

    Atmosphere-Ionosphere Coupling & its Role in Space Weather

  • Dynamical impacts of 2xCO2 on thermosphere: How do the circulation and tides change? International conference

    Huixin LIU

    IUGG  2023.7 

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    Language：Others   Presentation type：Oral presentation (general)  

    Country：United States  

    Response of thermosphere and ionosphere to increasing CO2

  • Long-term trends in foF2 and foEs over Japan and Antarctic Invited International conference

    Huixin LIU

    URSI  2023.8 

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    Language：English   Presentation type：Oral presentation (general)  

    Country：United States  

    Long-term trends in foF2 and foEs over Japan and Antarctic

  • Long-term trends in foF2 and foEs over Japan and Antarctic Invited International conference

    Huixin LIU

    CGS  2023.11 

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    Language：Others   Presentation type：Oral presentation (general)  

    Country：United States  

    Long-term trends in foF2 and foEs over Japan and Antarctic

  • Response of thermosphere and ionosphere to increasing CO2 International conference

    Huixin LIU

    AGU2023  2023.12 

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    Language：Others   Presentation type：Oral presentation (general)  

    Country：United States  

    Response of thermosphere and ionosphere to increasing CO2

  • DW1 tidal enhancements in the equatorial MLT during 2015 El Nino: the relative role of tidal heating and propagation Invited

    Huixin Liu

    SCOSTEP Presto workshop  2023.5 

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    Event date： 2023.5

    Presentation type：Oral presentation (keynote)  

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  • Atmosphere-Ionosphere Coupling and Its role in Space Weather Invited

    Huixin Liu

    8th IAGA/ICMA/SCOSTEP workshop on vertical coupling in the atmosphere-ionosphere system  2022.7 

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    Event date： 2022.7

    Language：English   Presentation type：Oral presentation (keynote)  

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  • DW1 enhancement in MLT during 2015 El Niño Invited

    Huixin Liu

    15TH QUADRENNIAL SOLAR-TERRESTRIAL PHYSICS SYMPOSIUM (STP-15)  2022.2 

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    Event date： 2022.2

    Language：English   Presentation type：Oral presentation (invited, special)  

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  • Seismo-electromagnetic anomalies in ELF range observed by an induction magnetometer in Kuju

    田中 大次郎, Liu Huixin, Yumoto Kiyohumi

    地球電磁気・地球惑星圏学会  2012.11 

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    Event date： 2012.10

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sapporo   Country：Japan  

  • Response of the global ionospheric current system to stratosphere sudden warming International conference

    Y. Yamazaki, K. Yumoto, Huixin Liu, D. Mcnamara, K. Kitamura

    JPGU  2012.5 

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    Event date： 2012.5

    Presentation type：Oral presentation (general)  

    Venue：Makuhari   Country：Japan  

  • Response of thermosphere and ionosphere to increasing CO2 Invited

    Huixin Liu

    International symposium for Equatorial Aeronomy  2022.9 

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    Presentation type：Oral presentation (invited, special)  

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  • Response of thermosphere and ionosphere to increasing CO2 Invited

    Huixin LIU

    NASA Goddard Special Seminar  2023.3 

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    Presentation type：Oral presentation (invited, special)  

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MISC

  • Large-scale structures and ion-neutral coupling in Cross-scale coupling and energy transfer in the magnetosphere-ionosphere-thermosphere system Reviewed

    Huixin Liu, Scott England

    https://doi.org/10.1016/B978-0-12-821366-7.00003-2   2022.10

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： https://doi.org/10.1016/B978-0-12-821366-7.00003-2

  • SpaceX-Sailing close to the space weather? Reviewed

    Hapgood, M., Huixin Liu, N. Lugaz

    Space Weather   2022.3

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： https://doi.org/10.1029/2022SW003074

  • Machine-learning research in the Space Weather journal: prospects, scope, and limitations Reviewed

    Lugaz, N., Huixin Liu, M. Hapgood, S. Morley

    Space Weather   2021.12

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： https://doi.org/10.1029/2021SW003000

  • Day-to-day variability of the thermosphere and ionosphere Reviewed

    Huixin Liu, Y. Yamazaki, J. Lei

    アメリカ地球物理連合   2021.5

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： DOI: 10.1002/9781119815631.ch15

  • Sudden Stratospheric Warming Impacts on the Ionosphere– Thermosphere System: A Review of Recent Progress Reviewed

    Larisa P. Goncharenko, V. Lynn Harvey, Huixin Liu, and Nicholas M. Pedatella

    アメリカ地球物理連合   2021.5

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： DOI: 10.1002/9781119815631.ch15

  • Space Weather as the nexus of applied and fundamental space science: the need for separate funding mechanisms and definition Reviewed

    Lugaz, N., J. Gannon, M. Hapgood, Huixin Liu, T. Paul O’Brien

    Space Weather   2020.12

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： https://doi.org/10.1029/2020SW002695

  • The non-storm time corrugated upper thermosphere: What's beyond MSIS?

    Huixin Liu, J. Thayer, Y. Zhang, W. Lee

    Space Weather   2017.6

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    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： 10.1002/2017SW001618

  • CHAMP observations of the low latitude ionosphere and thermosphere and comparisons to physical models

    Claudia Stolle, Huixin Liu

    2014.2

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  • Thank You to Our 2022 Peer Reviewers

    Lugaz N., Carter B.A., Gannon J.L., Hapgood M., Liu H., Morley S., Zou S.

    Space Weather   21 ( 5 )   2023.5

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    Publisher：Space Weather  

    DOI： 10.1029/2023SW003534

    Scopus

  • Credit where credit is due: Data and software in the space weather community

    Steven Morley, Huixin Liu, Brett Carter, Jennifer Gannon, Noé Lugaz

    2022.12

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    Language：Others  

    DOI： 10.1002/essoar.10512999.1

  • Thank You to Our 2021 Peer Reviewers

    Lugaz N., Carter B.A., Gannon J.L., Hapgood M., Liu H., O’Brien T.P., Morley S.K., Zou S.

    Space Weather   20 ( 4 )   2022.4

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    Publisher：Space Weather  

    DOI： 10.1029/2022SW003116

    Scopus

  • 昼間スポラディックE層形成過程の中性大気とプラズマ大気の同時観測による解明—Elucidation of the generation process of daytime sporadic E Layers by simultaneous observation of the neutral and ionized atmospheres

    齊藤, 昭則, 阿部, 琢美, 松岡, 彩子, 石坂, 圭吾, 齋藤, 義文, 田川, 雅人, 熊本, 篤志, 斎藤, 享, 西岡, 未知, 細川, 敬祐, 横山, 竜宏, HUIXIN, Liu, SAITO, Akinori, ABE, Takumi, MATSUOKA, Ayako, ISHISAKA, Keigo, SAITO, Yoshifumi, TAGAWA, Masato, KUMAMOTO, Atsushi, SAITO, Susumu, NISHIOKA, Michi, HOSOKAWA, Keisuke, YOKOKAWA, Tatsuhiro

    観測ロケットシンポジウム2021 講演集 = Proceedings of Sounding Rocket Symposium 2021   2022.3

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    Language：Japanese   Publisher：宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)  

    第4回観測ロケットシンポジウム（2022年3月14-15日. ハイブリッド開催（JAXA相模原キャンパス& オンライン）)
    4th Sounding Rocket Symposium(March 14-15, 2022. Hybrid(in-person & online) Conference (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan
    著者人数: 12名
    資料番号: SA6000175010
    レポート番号: Ⅱ-5

    CiNii Research

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  • Thank You to Our 2019 Reviewers

    Noé Lugaz, Delores J. Knipp, Jennifer L. Gannon, Michael Hapgood, Huixin Liu, T. Paul O'Brien, Daniel T. Welling

    Space Weather   2020.3

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    Language：Others  

    DOI： 10.1029/2020SW002481

  • Role of the pre-reversal enhancement and medium-scale gravity waves on multiple plasma bubbles occurrence

    Prayitno Abadi, Yuichi Otsuka, Kazuo Shiokawa, Mamoru Yamamoto, Huixin Liu, Tatsuhiro Yokoyama

    日本地球惑星科学連合2018年大会   2018.5

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    Language：Others  

    Role of the pre-reversal enhancement and medium-scale gravity waves on multiple plasma bubbles occurrence

  • 新・衛星＝地上ビーコン観測と赤道大気レーダーによる低緯度電離圏の時空間変動の解明 －新しい研究プロジェクト紹介 －

    山本衛, 橋口浩之, 斎藤昭則, 松永真由美, 斎藤亨, Huixin Liu, 横山竜宏, 陣英克・Rola, Tsunoda・Tung-Yuan Hsiao

    第9回MUレーダー・赤道大気レーダーシンポジウム報告書   2015.9

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    Language：Others  

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Professional Memberships

  • Society of Geomagnetism and Earth, Planetary and Space Science

  • American Geophysical Union

  • European Geophysical Union

  • Asia Oceania Geophysical Society

  • Japan Geophysical Union

  • Japan Meteorogical Society

  • AOGS

  • European Geophysical Union

  • American Geophysical Union

  • JAPAN GEOSCIENCE UNION

  • SGEPSS

  • Asia Oceania Geophysical Society

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  • European Geophysical Union

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  • Japan Meteorogical Society

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  • JAPAN GEOSCIENCE UNION

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  • Society of Geomagnetism and Earth, Planetary and Space Science

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  • American Geophysical Union

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Committee Memberships

  • CEDAR, NSF, USA   Steering committee member  

    2020.6 - 2023.6   

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    Committee type：Academic society

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  • 国際地球電磁気学・超高層物理学協会(IAGA/IUGG)   IAGA/IUGG executive committee member  

    2019.7 - 2023.7   

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    Committee type：Academic society

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  • アメリカ地球物理連合   AGU executive committee  

    2018 - 2023.12   

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    Committee type：Academic society

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  • JpGU science Program  

    2017.5   

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    Committee type：Academic society

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  • アメリカ地球物理連合(AGU)　Honors＆Awards 委員会   Councilor   Foreign country

    2024.1 - 2025.12   

  • アメリカ地球物理連合   表彰委員会委員  

    2024.1 - 2025.12   

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  • International Associate for Geomagnetism and Aeronomy（IAGA）   Executive   Foreign country

    2023.8 - 2027.7   

  • International Associate for Geomagnetism and Aeronomy（IAGA）   Financial committee Chair   Foreign country

    2023.8 - 2027.7   

  • IAGA   Financial Committee Chair  

    2023.7 - 2027.7   

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    Committee type：Academic society

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  • アメリカ NSF CEDAR   Steering committee member   Foreign country

    2020.6 - 2023.5   

  • 日本地球惑星科学連合   国際戦略委員会委員   Foreign country

    2020.6 - 2023.5   

  • アメリカ NSF CEDAR   Steering committee member   Foreign country

    2020.6 - 2023.5   

  • アメリカ NSF CEDAR   運営委員  

    2020.6 - 2023.5   

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  • JpGU   Global Strategy Committee  

    2020.5 - 2023.4   

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    Committee type：Academic society

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  • 日本学術会議・地球惑星科学委員会・IUGG分科会　IAGA小委員会   Steering committee member   Domestic

    2020.2 - 2024.9   

  • 日本学術会議・地球惑星科学委員会・IUGG分科会 IAGA小委員会   運営委員  

    2020.2 - 2024.9   

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  • IUGG 地磁気と地球物理学国際連合   Steering committee member   Foreign country

    2019.9 - 2023.8   

  • IUGG 地磁気と地球物理学国際連合   Executive committee   Foreign country

    2019.9 - 2023.8   

  • アメリカ地球物理学会   Steering committee member   Foreign country

    2018.6 - 2021.5   

  • アメリカ地球物理学会   Committee for International Participants   Foreign country

    2018.6 - 2021.5   

  • 日本学術会議　電気電子工学委員会　URSI 分科会   委員   Foreign country

    2018.4 - 2020.9   

  • 日本学術会議　電気電子工学委員会　URSI 分科会   委員   Foreign country

    2016.10 - 2018.3   

  • 日本地球惑星科学連合   Steering committee member   Foreign country

    2016.6 - 2018.5   

  • 日本地球惑星科学連合   宇宙科学ボードメンバー   Foreign country

    2016.6 - 2018.5   

  • 日本地球惑星科学連合   サイエンスプログラム委員長   Foreign country

    2016.6 - 2017.5   

  • SCOSTEP   日本代表  

    2014.1 - 2022.12   

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    Committee type：Academic society

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  • 日本学術会議　電気電子工学委員会　URSI 分科会   委員   Foreign country

    2012.3 - 2016.9   

  • 地球電磁気・地球惑星圏学会 MTI 分科会   世話人   Domestic

    2010.5 - 2015.4   

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Academic Activities

  • Editor for "Space Weather"

    Role(s)： Review, evaluation,　Peer review

    American Geophysical Union  2018.1 - Present

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    Type：Academic society, research group, etc. 

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  • NASA科研費審査委員

    Role(s)： Review, evaluation

    米国NASA  2017.10

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    Type：Scientific advice/Review 

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  • Editor for Ann. Geophysics

    Role(s)： Review, evaluation,　Peer review

    European Geophysical Union  2017.6 - Present

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    Type：Academic society, research group, etc. 

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  • Science Program Chair for JpGU-AGU joint meeting

    Role(s)： Planning, management, etc.

    JpGU -AGU  2017.5

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    Type：Competition, symposium, etc. 

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  • Session Convener/Chair for Atmosphere-ionosphere coupling session

    Role(s)： Panel moderator, session chair, etc.

    2011.5 - Present

    　More details

    Type：Competition, symposium, etc. 

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  • コンビーナ（convener ） + Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2024.5 - 2022.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：10,000

  • 全国共同利用施設評価員

    Role(s)： Review, evaluation

    2024.4 - 2024.6

    　More details

    Type：Scientific advice/Review 

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  • 全学共同利用・共同研究審査員

    Role(s)： Review, evaluation

    日本学術振興会  2024.4

    　More details

    Type：Scientific advice/Review 

  • Editor for "Progress in Earth and Planetary Science"

    Role(s)： Peer review

    2024.1 - 2026.12

    　More details

  • Progress in Earth and Planetary Science International contribution

    2024.1 - 2027.12

    　More details

    Type：Academic society, research group, etc. 

  • コンビーナ（convener ） + Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2023.5 - 2022.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：10,000

  • コンビーナ（convener ） + Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2022.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：8,000

  • Earth Planet Space International contribution

    2022.1 - 2022.12

    　More details

    Type：Academic society, research group, etc. 

  • Screening of academic papers

    Role(s)： Peer review

    2022

    　More details

    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：150

  • コンビーナ（convener ） + Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2021.5 - 2021.6

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：8,000

  • Screening of academic papers

    Role(s)： Peer review

    2021

    　More details

    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：100

  • コンビーナ（convener ） + Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2020.7

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：8,000

  • Screening of academic papers

    Role(s)： Peer review

    2020

    　More details

    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：70

  • Co-Convenor+座長（Chairmanship） International contribution

    American Geophysical Union  （ Washington D. C. UnitedStatesofAmerica ） 2019.12 - 2018.12

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：30,000

  • コンビーナ（convener ） + Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2019.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：8,000

  • 審査員

    Role(s)： Review, evaluation

    日本学術振興会  2019.4 - 2020.3

    　More details

    Type：Scientific advice/Review 

  • Convener, Chair International contribution

    American Geophysical Union Chapman Conference  （ Pasadena UnitedStatesofAmerica ） 2019.2

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：100

  • Screening of academic papers

    Role(s)： Peer review

    2019

    　More details

    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：60

  • Co-Convenor+座長（Chairmanship） International contribution

    American Geophysical Union  （ Washington D. C. UnitedStatesofAmerica ） 2018.12

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：30,000

  • 座長（Chairmanship） International contribution

    AOGS  （ Honolulu UnitedStatesofAmerica ） 2018.6

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    Type：Competition, symposium, etc. 

    Number of participants：3,000

  • Convener International contribution

    AOGS  （ Honolulu UnitedStatesofAmerica ） 2018.6

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：3,000

  • コンビーナ（convener ） International contribution

    日本地球惑星連合JpGU  （ Japan ） 2018.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：7,000

  • サイエンスプログラム副委員長 International contribution

    日本地球惑星連合JpGU  （ Japan ） 2018.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：7,000

  • 座長Chair International contribution

    日本地球惑星連合JpGU  （ Japan ） 2018.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：7,000

  • 審査員

    Role(s)： Review, evaluation

    日本学術振興会  2018.4 - 2020.3

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    Type：Scientific advice/Review 

  • Space Weather International contribution

    2018.1 - 2023.12

    　More details

    Type：Academic society, research group, etc. 

  • Screening of academic papers

    Role(s)： Peer review

    2018

    　More details

    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：56

  • 審査・評価

    NASA科研費審査委員  （ Japan ） 2017.10 - Present

    　More details

    Type：Competition, symposium, etc. 

  • Program Chair, Main Convenor, Chairperson

    日本地球惑星科学連合（JPGU）  （ Makuhari Japan ） 2017.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 座長（Chairmanship） International contribution

    日本地球惑星連合JpGUーアメリカ地球物理連合AGU合同大会  （ Japan ） 2017.5 - 2016.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：8,700

  • サイエンスプログラム委員長 International contribution

    日本地球惑星連合JpGUーアメリカ地球物理連合AGU合同大会  （ Japan ） 2017.5 - 2016.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：8,700

  • コンビーナ（convener ） International contribution

    日本地球惑星連合JpGUーアメリカ地球物理連合AGU合同大会  （ Japan ） 2017.5 - 2016.5

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    Type：Competition, symposium, etc. 

    Number of participants：8,700

  • 企画立案・運営等

    日本地球惑星科学連合・アメリカ地球物理連合合同大会サイエンスプログラム委員長  （ Japan ） 2017.5 - Present

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    Type：Competition, symposium, etc. 

  • Ann. Geophysics International contribution

    2017.5 - 2022.12

    　More details

    Type：Academic society, research group, etc. 

  • Screening of academic papers

    Role(s)： Peer review

    2017

    　More details

    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：15

  • 座長（Chairmanship） International contribution

    The International Whole Atmospherear Symposium  （ Tokyo Japan ） 2016.9

    　More details

    Type：Competition, symposium, etc. 

  • 座長（Chairmanship）

    Mesosphere-Thermosphere-ionosphere workshop  （ Tokyo Japan ） 2016.9

    　More details

    Type：Competition, symposium, etc. 

  • Earth Planet Space International contribution

    2016.9 - 2021.12

    　More details

    Type：Academic society, research group, etc. 

  • 座長（Chairmanship） International contribution

    AOGS  （ Beijing China ） 2016.8

    　More details

    Type：Competition, symposium, etc. 

  • 座長（Chairmanship） International contribution

    VarSITI/ SCOSTEP symposium  （ Varna Bulgaria ） 2016.6

    　More details

    Type：Competition, symposium, etc. 

  • 座長（Chairmanship） International contribution

    日本地球惑星連合JpGU  （ Japan ） 2016.5

    　More details

    Type：Competition, symposium, etc. 

  • こんびーナ（convener ） International contribution

    日本地球惑星連合JpGU  （ Japan ） 2016.5

    　More details

    Type：Competition, symposium, etc. 

  • サイエンスプログラム副委員長 International contribution

    日本地球惑星連合JpGU  （ Japan ） 2016.5

    　More details

    Type：Competition, symposium, etc. 

  • Vice Science Program Chair, Main Convenor, Chairperson

    日本地球惑星科学連合（JPGU）  （ Makuhari Japan ） 2016.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 審査員

    Role(s)： Review, evaluation

    日本学術振興会  2016.4 - 2018.3

    　More details

    Type：Scientific advice/Review 

  • Screening of academic papers

    Role(s)： Peer review

    2016

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    Type：Peer review 

    Number of peer-reviewed articles in foreign language journals：10

  • 座長（Chairmanship） International contribution

    AOGS  （ Singapore Singapore ） 2015.8 - 2014.8

    　More details

    Type：Competition, symposium, etc. 

  • 座長（Chairmanship） International contribution

    日本地球惑星連合JpGU  （ Japan ） 2015.5

    　More details

    Type：Competition, symposium, etc. 

  • Chairperson International contribution

    日本地球惑星連合JpGU  （ Japan ） 2015.5

    　More details

    Type：Competition, symposium, etc. 

  • convener International contribution

    日本地球惑星連合JpGU  （ Japan ） 2015.5

    　More details

    Type：Competition, symposium, etc. 

  • Main Convenor, Chairperson

    日本地球惑星科学連合（JPGU）  （ Makuhari Japan ） 2015.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 世話人、プログラM委員長

    地球電磁気・地球惑星圏学会, 中間圏・熱圏・電離圏(MTI)分科会研究会  （ Japan ） 2014.9

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    Type：Competition, symposium, etc. 

    Number of participants：60

  • 座長（Chairmanship）

    H26年度 MTI研究集会  （ NICT, Tokyo Japan ） 2014.9

    　More details

    Type：Competition, symposium, etc. 

  • Main Convenor, Chairperson International contribution

    アジア太平洋地球物理学会AOGS  （ Sapporo Japan ） 2014.7 - 2014.8

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：3,000

  • 座長（Chairmanship） International contribution

    AOGS  （ Sapporo Japan ） 2014.7 - 2014.8

    　More details

    Type：Competition, symposium, etc. 

  • Main Convenor, Chairperson

    日本地球惑星科学連合（JPGU）  （ Makuhari Japan ） 2014.5 - 2015.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 座長（Chairmanship） International contribution

    日本地球惑星連合  （ Yokohama Japan ） 2014.4 - 2014.5

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    Type：Competition, symposium, etc. 

  • 座長 International contribution

    Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium  （ Nagoya Japan ） 2013.11

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    Type：Competition, symposium, etc. 

    Number of participants：300

  • 座長（Chairmanship） International contribution

    Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium  （ Nagoya Japan ） 2013.11

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    Type：Competition, symposium, etc. 

  • 世話人、プログラM委員長

    地球電磁気・地球惑星圏学会, 中間圏・熱圏・電離圏(MTI)分科会研究会  （ Japan ） 2013.9

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    Type：Competition, symposium, etc. 

    Number of participants：60

  • 座長（Chairmanship）

    H25年度 MTI研究集会  （ NICT, Tokyo Japan ） 2013.9

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    Type：Competition, symposium, etc. 

  • 座長 International contribution

    Workshop on Whole Atmosphere Coupling During Solar Cycle 24  （ National Central University, Taiwan Taiwan ） 2013.7

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：100

  • 座長（Chairmanship） International contribution

    Workshop on Whole Atmosphere Coupling During Solar Cycle 24  （ Chunli Taiwan ） 2013.7

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    Type：Competition, symposium, etc. 

  • Main Convenor, Chairperson

    日本地球惑星科学連合（JPGU）  （ Makuhari Japan ） 2013.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 座長（Chairmanship） International contribution

    日本地球惑星連合  （ Japan ） 2013.5 - 2012.5

    　More details

    Type：Competition, symposium, etc. 

  • 座長（Chairmanship）

    地球電磁気・地球惑星圏学会　２０１２秋学会  （ Japan ） 2012.10

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    Type：Competition, symposium, etc. 

  • Convenor, Chairperson

    地球電磁気・地球惑星圏学会（SGEPSS）  （ Sapporo Japan ） 2012.10

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    Type：Competition, symposium, etc. 

    Number of participants：500

  • 世話人、プログラM委員長

    地球電磁気・地球惑星圏学会, 中間圏・熱圏・電離圏(MTI)分科会研究会  （ Japan ） 2012.8

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    Type：Competition, symposium, etc. 

    Number of participants：60

  • Main Convenor, Chairperson

    日本地球惑星科学連合（JPGU）  （ Makuhari Japan ） 2012.5

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 座長（Chairmanship） International contribution

    日本地球惑星連合  （ Japan ） 2012.5

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    Type：Competition, symposium, etc. 

  • 世話人、及び LOC委員長

    地球電磁気・地球惑星圏学会, 中間圏・熱圏・電離圏(MTI)分科会研究会  （ Japan ） 2011.8

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    Type：Competition, symposium, etc. 

    Number of participants：60

  • 世話人、LOC委員長

    地球電磁気・地球惑星圏学会, MTI分科会　研究会  （ Japan ） 2011.8

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    Type：Competition, symposium, etc. 

  • 座長 International contribution

    IUGG  （ Melbourne Australia ） 2011.6 - 2011.7

    　More details

    Type：Competition, symposium, etc. 

    Number of participants：6,000

  • 座長（Chairmanship） International contribution

    IUGG 2011 学会  （ Melbourne Australia ） 2011.6 - 2011.7

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    Type：Competition, symposium, etc. 

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Other

  • JpGU 学会 highlight: GPS 通信障害の原因となるプラズマバブルの発生源に迫る

    2018.5

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    GPS システムは高度約 100km 以上の電離圏で発生するプラズマバブル(EPB)と呼ばれる現象に 大きく影響される。EPB の発生源が電離圏 F 下部の大気重力波であるかどうかは長年議論された が、この領域の中性大気観測が難しいため不明であった。本研究は世界初の電離圏 F 層下部その 場観測を利用し、中規模重力波の全球分布と季節変動を明らかにしたことで、GPS に障害を与え る EPB を予測するのに重要な意味がある。

  • JpGU 学会 highlight: GPS 通信障害の原因となるプラズマバブルの発生源に迫る

    2018.5

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    GPS システムは高度約 100km 以上の電離圏で発生するプラズマバブル(EPB)と呼ばれる現象に 大きく影響される。EPB の発生源が電離圏 F 下部の大気重力波であるかどうかは長年議論された が、この領域の中性大気観測が難しいため不明であった。本研究は世界初の電離圏 F 層下部その 場観測を利用し、中規模重力波の全球分布と季節変動を明らかにしたことで、GPS に障害を与え る EPB を予測するのに重要な意味がある。

    researchmap

  • Ms. Hisako Koyama: From Amateur Astronomer to Long-Term Solar Observer

    2017.10

  • AGU Press Release: ４０年間黒点記録をした小山ひさ子氏の太陽観測へ貢献を評価した論文

    2017.10

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  • Medium-scale gravity wave activity in the bottomside F region in tropical regions

    2017.7

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    欧州 ESA の「GOCE」衛星観測を用い、電離圏下部における中規模重力波の全球分布を初めて示し た。特に赤道域では海の上空より陸の上空で活発になっていることがわかった。また、重力波が 活発な地域ではプラズマバブルも多く、バブルの発生源が重力波である可能性を裏付けた。重力 波は熱帯対流活動で励起され、砕波と 2 次波の再生により電離圏まで伝搬することで天気と宇宙 現象のつながりを示唆している。

  • Response of diurnal tides to ENSO in the MLT region: a 21-year　reanalysis GAIA model simulation result

    2017.5

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    エルニーニョ南方振動(ENSO)とは、赤道太平洋の海面 水温が数か月- 数十か月にわたって上昇または下降する地 球規模での自然現象であ る。ENSO は顕著な気候変動をもたらすだけではなく、400km 以上 の超高層大気へも影響を及ぼしていることを本研究で46年の衛星 観測の分析からわかった。さらに、数値シミュレーションによって、 そのテレコネクションを果たすのは気候に左右される下層大気潮汐 であることを明らかにした。

  • JpGU research highlight: 海面から超高層大気まで:エルニーニョが上層大気にもたらす影響を迫る

    2017.5

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    エルニーニョ南方振動(ENSO)とは、赤道太平洋の海面 水温が数か月- 数十か月にわたって上昇または下降する地 球規模での自然現象であ る。ENSO は顕著な気候変動をもたらすだけではなく、400km 以上 の超高層大気へも影響を及ぼしていることを本研究で46年の衛星 観測の分析からわかった。さらに、数値シミュレーションによって、 そのテレコネクションを果たすのは気候に左右される下層大気潮汐 であることを明らかにした。

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▼display all

Research Projects

  • レーダー観測網・複数衛星・モデル計算を総合した太陽地球系宇宙天気の国際共同研究

    Grant number：22K21345  2024 - 2026

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  International Leading Research

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    Authorship：Coinvestigator(s)  Grant type：Scientific research funding

  • 電離圏突発E層の研究について International coauthorship

    2023.4 - 2026.3

    日本 

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    Authorship：Principal investigator 

  • 火星の大気圏・電離圏結合過程について International coauthorship

    2023.4 - 2026.3

    日本 

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    Authorship：Principal investigator 

  • International study of equatorial ionosphere based on observations and models

    Grant number：20H00197  2020 - 2024

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    山本 衛, 横山 竜宏, 橋口 浩之, 齊藤 昭則, 大塚 雄一, Liu Huixin, 三好 勉信, 齋藤 享, HOZUMI KORNYANAT

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    Authorship：Coinvestigator(s)  Grant type：Scientific research funding

    強い不安定現象である赤道プラズマバブル(Equatorial PlasmaBubble; EPB)の国際共同研究を実施する。EPB活動度が日々変動する原因として有力なLarge-Scale Wave Structure (LSWS)仮説がある。その検証を目指して、赤道大気レーダーと観測網SEALIONによる連続観測を継続、GNSS (衛星測位)受信機を増強する。地表から電離圏までの全大気計算モデルGAIA、EPBの生成・成長を正確に模擬する非線形計算モデルを活用した研究を推進する。地上観測、衛星観測、シミュレーションを駆使した総合研究に取り組むもので、世界をリードする成果が期待される。

    CiNii Research

  • 年々変動と長期トレンドにおける中層大気と超高層大気結合：大気波動の役割を探る (ドイツとの国際共同研究プログラム) International coauthorship

    2019.3 - 2023.3

    日本 

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    Authorship：Principal investigator 

  • 年々変動と長期トレンドにおける中層大気と超高層大気結合：大気波動の役割を探る(Wave coupling processes of the middle and upper atmosphere: Interannual and long- term variability)

    2019 - 2023

    Japan Society for the Promotion of Science  国際共同研究事業DFG-JSPS lead with DFG : ドイツとの国際共同研究プログラム

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    Authorship：Principal investigator  Grant type：Joint research

  • 年々変動と長期トレンドにおける中層大気と超高層大気結合:大気波動の役割を探る

    2019 - 2022

    Fund for Promoting Science and Technology (major five fields) (Ministry of Education, Culture, Sports, Science and Technology)

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    Authorship：Principal investigator  Grant type：Contract research

  • 熱圏直接観測による中規模大気重力波と電離圏プラズマバブルの発生関係の検証

    2018.4 - 2024.3

    日本 

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    Authorship：Principal investigator 

  • エルニーニョ気候変動に対する超高層大気の応答とそのメカニズムの解明　ー　国際共同研究加速

    2018.4 - 2023.3

    日本 

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    Authorship：Principal investigator 

  • ENSO気候変動は超高層大気をどう揺らすのか:成層圏オゾンが果たす役割の解明

    2018.4 - 2023.3

    日本 

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    Authorship：Principal investigator 

  • 熱圏重力波と電離圏プラズマバブルの発生関係の検証

    2018.4 - 2019.3

    Joint research

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    Authorship：Principal investigator  Grant type：Other funds from industry-academia collaboration

  • ENSO気候変動は超高層大気をどう揺らすのか:成層圏オゾンが果たす役割の解明

    Grant number：18H01270  2018 - 2023

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    Liu Huixin, 山本 衛, 江口 菜穂, 陣 英克, 廣岡 俊彦

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    Authorship：Principal investigator  Grant type：Scientific research funding

    対流圏と海洋間の相互作用現象であるエルニーニョ・南方振動(ENSO)が、数百km上空の超高層大気領域（熱圏・電離圏）にまで影響を及ぼすことが長期間観測から見出されている。本研究では、この数百km間の上下結合において、成層圏オゾンが駆動する放射・力学過程を、観測データの総合解析と高精度数値モデルを駆使して解明する。今年度はオゾン変動が中間圏・下部熱圏に及ぼす力学的影響を解明した。具体的に、全大気モデルを用いて、2012年のエルニーニョを再現して、対流圏オゾンの空間分布を変化させるシミュレーションを行った。その結果、対流圏オゾン変調は、高度約20kmから約100kmまでのDW2潮汐を約5％強めることがわかった。これは水蒸気変調による大気潮汐変化（約８０％）に比べて小さいことがわかった。また、GAIAモデルによるシミュレーションを行い、熱圏の帯状 平均運動量バランスを調べることで、CO2濃度2倍に対する熱圏帯状平均風の応答メカニズムを探った。解析の結果、イオン抵抗、分子粘性、子午線圧力勾配力 は、CO2濃度の2倍化によって他の力も変化することがわかった。この3つの力は互いに強く減衰し、その結果、帯状平均帯状イオン抗力の増加が 支配的に強化される。このイオン抵抗の強化は、北半球/南半球でイオン密度/イオンと中性粒子間の相対速度が増加することに起因する。一方、帯状風は、CO2 濃度増加に対する熱圏密度の緯度非対称な応答による子午線圧力勾配力の増加によって主に変化することがわかった。この結果は、北半球のイオン密度の増加 が、CO2濃度増加に対する風の応答の根本的なトリガーであることを示唆している。

    CiNii Research

  • エルニーニョ気候変動がもたらす大気潮汐波動変化の解明

    Grant number：17KK0095  2018 - 2023

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Fostering Joint International Research (A)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • 年々変動と長期トレンドにおける中層大気と超高層大気結合：大気波動の役割を探る(Wave coupling processes of the middle and upper atmosphere: Interannual and long- term variability)

    Grant number：JPJSJRP20181602  2018 - 2023

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Fostering Joint International Research

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • エルニーニョ気候変動に対する超高層大気の応答とそのメカニズムの解明

    Grant number：17KK0095  2018 - 2023

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Fostering Joint International Research (A)

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

  • 熱圏直接観測による中規模大気重力波と電離圏プラズマバブルの発生関係の検証

    Grant number：18H04446  2018 - 2019

    Japan Society for the Promotion of Science・Ministry of Education, Culture, Sports, Science and Technology  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • 熱圏直接観測による中規模大気重力波と電離圏プラズマバブルの 発生関係の検証

    2018 - 2019

    Japan Society for the Promotion of Science・Ministry of Education, Culture, Sports, Science and Technology  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • 南極中間圏潮汐の気候変動:観測とモデルの比較

    2017.4 - 2018.3

    Joint research

    　 More details

    Authorship：Principal investigator  Grant type：Other funds from industry-academia collaboration

  • Impact of El Nino Southern Oscillation on the Middle and Upper Atmosphere

    2017 - 2019

    ICSWSE国際宇宙天気科学教育センター共同研究

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    Authorship：Principal investigator  Grant type：On-campus funds, funds, etc.

  • 成層圏突然昇温による中緯度での電離圏熱圏変動の研究

    2016

    独立行政法人情報通信研究機構　国際交流プログラム

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    Authorship：Principal investigator  Grant type：Contract research

  • 新・衛星=地上ビーコン観測と赤道大気レーダーによる低緯度電離圏の時空間変動の 解明

    2015.4 - 2025.3

    日本 

    　 More details

    Authorship：Coinvestigator(s) 

  • エルニーニョ気候変動に対する超高層大気の応答とそのメカニズムの解明

    2015.4 - 2024.3

    　 More details

    Authorship：Principal investigator 

  • 高分解能版大気圏・電離圏モデルによる熱圏重力波の研究

    2015.4 - 2019.3

    日本 

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    Authorship：Coinvestigator(s) 

  • 新•衛星＝地上ビーコン観測と赤道大気レーダーによる低緯度電離圏の時空間変動の解明

    Grant number：15H02135  2015 - 2018

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

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    Authorship：Coinvestigator(s)  Grant type：Scientific research funding

  • 高分解能版大気圏・電離圏モデルによる熱圏重力波の研究

    Grant number：15H03733  2015 - 2018

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant type：Scientific research funding

  • 新・衛星＝地上ビーコン観測と赤道大気レーダーによる低緯度電離圏の時空間変動の解明

    Grant number：15H02135  2015 - 2018

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant type：Scientific research funding

  • 高分解能版大気圏・電離圏モデルによる熱圏重力波の研究

    Grant number：15H03733  2015 - 2018

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Authorship：Coinvestigator(s)  Grant type：Scientific research funding

  • エルニーニョ気候変動に対する超高層大気の応答とそのメカニズムの解明

    Grant number：15K05301  2015 - 2017

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • エルニーニョ気候変動に対する超高層大気の応答とそのメカニズムの解明

    2015 - 2017

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • Interannual variation of the thermosphere/ionosphere

    2015 - 2016

    ICSWSE国際宇宙天気科学研究教育センター共同研究

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    Authorship：Principal investigator  Grant type：On-campus funds, funds, etc.

  • 成層圏突然昇温による南極での中間圏・熱圏・電離圏変動

    2014.4 - 2017.3

    Joint research

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    Authorship：Principal investigator  Grant type：Other funds from industry-academia collaboration

  • 大地震の電離層擾乱前駆現象の研究

    2014 - 2015

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant type：Scientific research funding

  • 大地震の電離層擾乱前駆現象の研究

    2014 - 2015

    三菱財団自然科学研究助成金

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    Authorship：Coinvestigator(s)  Grant type：Contract research

  • 成層圏準2年振動が熱圏・電離圏に及ぼす影響について Possible effects of the Quasi-Biennial Oscillation on the Thermosphere / Ionosphere

    2014

    独立行政法人情報通信研究機構　国際交流プログラム

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    Authorship：Principal investigator  Grant type：Contract research

  • 三菱財団自然科学研究助成 (分担) / 大地震の電離層擾乱前駆現象の研究

    2014

    　 More details

    Grant type：Donation

  • 成層圏から超高層まで：成層圏突然昇温に対する熱圏降温現象の生成機構の解明

    2013.4 - 2015.3

    　 More details

    Authorship：Principal investigator 

  • 成層圏から超高層まで：成層圏突然昇温に対する熱圏降温現象の生成機構の解明

    Grant number：25800274  2013 - 2014

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Young Scientists (B)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • 成層圏から超高層まで：成層圏突然昇温に対する熱圏降温現象の生成機構の解明

    2013 - 2014

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • 成層圏から超高層まで：成層圏突然昇温に対する熱圏降温現象の解明

    2013 - 2014

    資生堂サイエスグランド

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    Authorship：Principal investigator  Grant type：Contract research

  • 太陽風—熱圏結合：熱圏大気密度の太陽風依存性の研究

    2013

    独立行政法人情報通信研究機構　国際交流プログラム

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    Authorship：Principal investigator  Grant type：Contract research

  • 資生堂女性研究者サイエンスグランド

    2013

    　 More details

    Grant type：Donation

  • 国際宇宙天気キャパシテイ•ビルデイング拠点の形成

    2012 - 2014

    Grants-in-Aid for Scientific Research  Grant-in-Aid for International Scientific Research

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    Grant type：Scientific research funding

  • True Global Sq Current System From Satellite Observations

    2012 - 2014

    国際宇宙科学研究教育センター

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    Authorship：Principal investigator  Grant type：On-campus funds, funds, etc.

  • Alfven waves によるオーロラ粒子の加速

    2012 - 2013

    独立行政法人情報通信研究機構　国際交流プログラム

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    Authorship：Principal investigator  Grant type：Contract research

  • 岩石圏ー大気圏ー電離圏結合

    2012

    独立行政法人情報通信研究機構　国際交流プログラム

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    Authorship：Principal investigator  Grant type：Contract research

  • 大気大循環モデルと超多点磁場観測データによる大気圏電離圏き協調現象の解明

    2011.4 - 2014.3

    　 More details

    Authorship：Coinvestigator(s) 

  • Thermosphere-Ionosphere coupling to lower atmosphere

    2011 - 2014

    女性研究者補助金

    　 More details

    Authorship：Principal investigator  Grant type：On-campus funds, funds, etc.

  • 大気大循環モデルと超多点磁場観測データによる大気圏電離圏協調現象の解明

    Grant number：23540513  2011 - 2013

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant type：Scientific research funding

  • 中間圏・熱圏・電離圏における大気・プラズマ結合過程の解明

    2009.4 - 2012.3

    　 More details

    Authorship：Principal investigator 

  • 中間圏・熱圏・電離圏における大気・プラズマ結合過程の解明

    Grant number：21•40008  2009 - 2012

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for JSPS Fellows

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • 中間圏•熱圏 • 電離圏における大気 • プラズマ結合過程の解明

    2009 - 2012

    Japan Society for the Promotion of Science  Research Fellowships for Young Scientists

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    Authorship：Principal investigator  Grant type：Joint research

  • 中間圏•熱圏•電離圏における大気•プラズマ結合過程の解明

    2009 - 2011

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship：Principal investigator  Grant type：Scientific research funding

  • The Thermosphere-Ionosphere Coupling at Low Latitudes

    2007 - 2008

    Japan Society for the Promotion of Science  Postdoctoral Fellowships for Research Abroad

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    Authorship：Principal investigator  Grant type：Joint research

  • 熱圏•電離圏における大気•プラズマ結合過程の解明

    2005 - 2007

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

▼display all

Educational Activities

  • 1. Earth and Planetary Science: an introduction
    2. Cosmic science
    3. Geospace physics
    4. Space electrodynamcs
    5. Helio-Geospace electromagnetism
    6. Kikan seminar
    7. Introduction to Physics: B

Award for Educational Activities

  • 文部科学大臣表彰若手科学者賞（2012年）

       

Class subject

  • 電磁圏・超高層大気物理学

    2024.10 - 2025.3   Second semester

  • 電磁気学

    2024.10 - 2025.3   Second semester

  • 解析演習

    2024.6 - 2024.8   Summer quarter

  • 宇宙科学概論

    2024.4 - 2024.9   First semester

  • 国際科学特論Ⅵ

    2024.4 - 2024.6   Spring quarter

  • 科学論文読解学入門

    2024.4 - 2024.6   Spring quarter

  • 電磁圏・超高層大気物理学

    2023.10 - 2024.3   Second semester

  • 解析演習

    2023.6 - 2023.8   Summer quarter

  • 基幹教育セミナー

    2023.6 - 2023.8   Summer quarter

  • 宇宙科学概論

    2023.4 - 2023.9   First semester

  • 科学論文読解学入門

    2023.4 - 2023.6   Spring quarter

  • 国際科学特論Ⅵ

    2023.4 - 2023.6   Spring quarter

  • 電磁圏・超高層大気物理学

    2022.10 - 2023.3   Second semester

  • 解析演習

    2022.6 - 2022.8   Summer quarter

  • 基幹教育セミナー

    2022.6 - 2022.8   Summer quarter

  • 宇宙科学概論

    2022.4 - 2022.9   First semester

  • 科学論文読解学入門

    2022.4 - 2022.6   Spring quarter

  • 国際科学特論Ⅵ

    2022.4 - 2022.6   Spring quarter

  • 電磁圏・超高層大気物理学

    2021.10 - 2022.3   Second semester

  • 電磁圏・超高層大気物理学

    2021.10 - 2022.3   Second semester

  • 電磁気学

    2021.10 - 2022.3   Second semester

  • 電磁気学概論

    2021.10 - 2021.12   Fall quarter

  • 解析演習

    2021.6 - 2021.8   Summer quarter

  • 解析演習

    2021.6 - 2021.8   Summer quarter

  • 科学論文読解学

    2021.4 - 2021.9   First semester

  • 科学論文読解学

    2021.4 - 2021.9   First semester

  • 宇宙科学概論

    2021.4 - 2021.9   First semester

  • 電磁圏・超高層大気物理学

    2020.10 - 2021.3   Second semester

  • 物理学概論Ｂ

    2020.10 - 2021.3   Second semester

  • 解析演習

    2020.6 - 2020.8   Summer quarter

  • 科学論文読解学

    2020.4 - 2020.9   First semester

  • 宇宙科学概論

    2020.4 - 2020.9   First semester

  • 電磁圏・超高層大気物理学

    2019.10 - 2020.3   Second semester

  • 基幹教育セミナー

    2019.6 - 2019.8   Summer quarter

  • 解析演習

    2019.6 - 2019.8   Summer quarter

  • 基幹教育セミナー

    2019.6 - 2019.8   Summer quarter

  • 科学論文読解学

    2019.4 - 2019.9   First semester

  • 宇宙科学概論

    2019.4 - 2019.9   First semester

  • 基幹教育セミナー

    2018.6 - 2018.8   Summer quarter

  • 基幹教育セミナー

    2018.6 - 2018.8   Summer quarter

  • 科学論文読解学

    2018.4 - 2018.9   First semester

  • 科学論文読解学

    2018.4 - 2018.9   First semester

  • 数理解析演習

    2018.4 - 2018.9   First semester

  • 宇宙科学概論

    2018.4 - 2018.9   First semester

  • 超高層大気電磁気物理

    2017.10 - 2018.3   Second semester

  • 電磁圏・超高層大気物理学

    2017.10 - 2018.3   Second semester

  • 電磁圏・超高層大気物理学

    2017.10 - 2018.3   Second semester

  • 地球惑星科学II

    2017.10 - 2018.3   Second semester

  • 基幹教育セミナー

    2017.6 - 2017.8   Summer quarter

  • 基幹教育セミナー

    2017.6 - 2017.8   Summer quarter

  • 宇宙科学概論

    2017.4 - 2017.9   First semester

  • 科学論文読解学

    2017.4 - 2017.9   First semester

  • 宇宙科学概論

    2017.4 - 2017.9   First semester

  • 科学論文読解学

    2017.4 - 2017.9   First semester

  • 宇宙科学概論

    2017.4 - 2017.9   First semester

  • 基幹教育セミナー

    2017.4 - 2017.9   First semester

  • 地球惑星解析演習

    2017.4 - 2017.9   First semester

  • 地球惑星科学英語

    2017.4 - 2017.9   First semester

  • 超高層大気電磁気物理

    2016.10 - 2017.3   Second semester

  • 物理概論B

    2016.10 - 2017.3   Second semester

  • 地球惑星解析演習

    2016.4 - 2016.9   First semester

  • 宇宙科学概論

    2016.4 - 2016.9   First semester

  • 地球惑星科学英語

    2016.4 - 2016.9   First semester

  • 地球惑星科学II

    2015.10 - 2016.3   Second semester

  • 超高層大気電磁気物理

    2015.10 - 2016.3   Second semester

  • 物理概論B

    2015.10 - 2016.3   Second semester

  • 宇宙科学概論

    2015.4 - 2015.9   First semester

  • 地球惑星解析演習

    2015.4 - 2015.9   First semester

  • 地球惑星科学英語

    2015.4 - 2015.9   First semester

  • 超高層大気電磁気物理

    2014.10 - 2015.3   Second semester

  • 地球惑星科学II

    2014.10 - 2015.3   Second semester

  • 物理概論B

    2014.10 - 2015.3   Second semester

  • 地球惑星科学英語

    2014.4 - 2014.9   First semester

  • 地球惑星解析演習

    2014.4 - 2014.9   First semester

  • 超高層大気電磁気物理

    2013.10 - 2014.3   Second semester

  • 地球惑星科学英語

    2013.4 - 2013.9   First semester

  • 地球惑星解析演習

    2013.4 - 2013.9   First semester

  • 宇宙科学概論

    2013.4 - 2013.9   First semester

  • Helio-Geospace electromagnetism

    2012.10 - 2013.3   Second semester

  • Earth and Planetary Science: an introduction

    2012.4 - 2012.9   First semester

  • コアセミナー

    2012.4 - 2012.9   First semester

  • Space electrodynamcs

    2012.4 - 2012.9   First semester

  • Geospace Physics

    2012.4 - 2012.9   First semester

  • Cosmic Science

    2012.4 - 2012.9   First semester

  • Helio-Geospace electromagnetism

    2011.10 - 2012.3   Second semester

▼display all

FD Participation

  • 2022.3   Role：Participation   Title：FD：野外活動について

    Organizer：Undergraduate school department

  • 2021.5   Role：Participation   Title：英語FD：オンライン講義のコツ

    Organizer：University-wide

  • 2013.10   Role：Planning   Title：教育の質向上支援プログラム(EEP)講演会

    Organizer：[Undergraduate school/graduate school/graduate faculty]

  • 2012.1   Role：Planning   Title：教育の質向上支援プログラム(EEP)講演会

    Organizer：[Undergraduate school/graduate school/graduate faculty]

Visiting, concurrent, or part-time lecturers at other universities, institutions, etc.

  • 2024  Leibniz Institute of Atmospheric Physics, University of Rostock, Germany  Classification:Intensive course  Domestic/International Classification:Overseas 

    Semester, Day Time or Duration：September

  • 2022  University of Oslo, Department of Geosciences  Classification:Part-time lecturer  Domestic/International Classification:Overseas 

    Semester, Day Time or Duration：Fall semester, August-November

  • 2022  Leibniz Institute of Atmospheric Physics, University of Rostock, Germany  Classification:Part-time lecturer  Domestic/International Classification:Overseas 

    Semester, Day Time or Duration：October-December

Participation in international educational events, etc.

  • 2023.5

    SCOSTEP (the Scientific Committee on Solar-Terrestrial Physics) and ISWI (International Space Weather Initiative, UN)

    SCOSTEP/ISWI School

    　 More details

    Venue：Italy, Trieste , ICTP(international center for theoretical physics)

    Number of participants：100

  • 2013.9

    九州大学国際宇宙天気研究教育センター（ICSWSE）

    MAGDAS/ISWI School

    　 More details

    Venue：コートジボアール, アビジャン (Cote d’Ivoire, Abidjan)

    Number of participants：80

  • 2012.9

    九州大学国際宇宙天気研究教育センター（ICSWSE）, NASA, SCOSSTEP

    ISWI and MAGDAS School

    　 More details

    Venue：Jakarta, Indonesia

    Number of participants：80

Other educational activity and Special note

  • 2023  Class Teacher  学部

  • 2022  Class Teacher  学部

  • 2020  Special Affairs  高校への出前講義

    　詳細を見る

    高校への出前講義

  • 2012  Class Teacher  学部

Outline of Social Contribution and International Cooperation activities

  • ３つの国際学会の執行部委員：　IAGA /IUGG執行部委員、経理委員長、アメリカ地球物理連合AGU・国際部アジア代表、表彰委員会　アメリカNational Science Foundation・CEDAR執行部委員

    国内学会　日本地球惑星科学連合・国際戦略部委員

Social Activities

  • 一般向け特別講演「空に見えない電離圏というものがある」

    Role(s)：Lecturer

    地球電磁気・惑星圏学会 

    　More details

    Type：Lecture

    researchmap

  • 電離圏と宇宙天気

    Role(s)：Lecturer

    福岡舞鶴高校 

    　More details

    Type：Visiting lecture

    researchmap

  • 外国人研究者としてみた日本の大学のダイバーシティ

    Role(s)：Interviewer

    日本地球惑星科学連合 

    　More details

    Type：Lecture

    researchmap

  • 電離圏と宇宙天気

    九州大学  西新プラザ  2023.7

    　More details

    Audience：General,　Scientific,　Company,　Civic organization,　Governmental agency

    Type：Lecture

    西新プラザで一般市民、小中高生を対象とした「電離圏と宇宙天気」に関するアウトリーチ活動を行い、社会貢献してきた。

  • 外国人研究者としてみた日本の大学のダイバーシティ

    日本地球惑星科学連合  2021.5

    　More details

    Audience：General,　Scientific,　Company,　Civic organization,　Governmental agency

  • 電離圏と宇宙天気

    福岡舞鶴高校  2020.11

    　More details

    Audience：General,　Scientific,　Company,　Civic organization,　Governmental agency

  • 第１４８回日本地球電磁気・地球惑星圏学会、一般向け特別講演会 https://www.sgepss.org/sgepss/fallmeeting/FM2020/LOC2020/lecture.html#special

    日本地球電磁気・地球惑星圏学会SGEPSS  https://www.sgepss.org/sgepss/fallmeeting/FM2020/LOC2020/lecture.html#special  2020.11

    　More details

    Audience：General,　Scientific,　Company,　Civic organization,　Governmental agency

    Type：Lecture

    電離圏研究と宇宙天気分野の最新研究結果を一般市民向けにわかりやすく解説する講演である。

  • 出前講義として、福岡舞鶴高校で「宇宙天気」について講義をしました。

    福岡舞鶴高校  2020.11

    　More details

    Audience：Infants,　Schoolchildren,　Junior students,　High school students

    Type：Other

  • 出前講義として、福岡舞鶴高校で「宇宙天気」について講義をしました。

    福岡舞鶴高校  2020.11

    　More details

    Type：Other

    researchmap

  • 第１４８回日本地球電磁気・地球惑星圏学会、一般向け特別講演会 https://www.sgepss.org/sgepss/fallmeeting/FM2020/LOC2020/lecture.html#special

    日本地球電磁気・地球惑星圏学会SGEPSS  https://www.sgepss.org/sgepss/fallmeeting/FM2020/LOC2020/lecture.html#special  2020.11

    　More details

    Type：Visiting lecture

    電離圏研究と宇宙天気分野の最新研究結果を一般市民向けにわかりやすく解説する講演である。

    researchmap

  • 一般向け特別講演「空に見えない電離圏というものがある」

    地球電磁気・惑星圏学会  2020.10

    　More details

    Audience：General,　Scientific,　Company,　Civic organization,　Governmental agency

▼display all

Media Coverage

  • Earth and space share the same turbulence Internet

    Eurekalert  press release  https://www.eurekalert.org/news-releases/1047473  2024.6

    　More details

    Author：Other 

    researchmap

  • Discovery of the energy cascading law in the thermosphere Promotional material

    Kyushu University, Press Release  九州大学プレスリリース  https://www.kyushu-u.ac.jp/ja/researches/view/1088  2024.6

    　More details

    Author：Other 

    researchmap

  • Earth and space share the same turbulence Promotional material

    Kyushu University Press  Kyushu University Press  https://www.kyushu-u.ac.jp/en/researches/view/289  2024.6

    　More details

    Author：Other 

    researchmap

  • 「Cultivating Tomorrow's Leaders」コラムで、「SENTAN-Q：paves the way for a diverse global future」と題して、九州大学SENTAN Qプログラムの経験とコメントを取り上げられた Newspaper, magazine

    Connect  2024.2

    　More details

    「Cultivating Tomorrow's Leaders」コラムで、「SENTAN-Q：paves the way for a diverse global future」と題して、九州大学SENTAN Qプログラムの経験とコメントを取り上げられた

  • 「国際色豊かな仲間と宇宙天気の謎に挑む」と題して、研究内容と研究室紹介を取り上げられた Newspaper, magazine

    九大広報　https://www.kyushu-u.ac.jp/f/55335/kyudaikoho128_web_2.pdf  2023.12

    　More details

    「国際色豊かな仲間と宇宙天気の謎に挑む」と題して、研究内容と研究室紹介を取り上げられた

  • 2015年エルニーニョの発生による大気潮汐の増加の定量的解明

    EoS ニューズレター  2021.8

    　More details

    2015年エルニーニョの発生による大気潮汐の増加の定量的解明

  • 外国人研究者と教員としてインタビューされました TV or radio program

    日本地球惑星科学連合大会、インタビュー企画プログラムに登場  2021.6

    　More details

    外国人研究者と教員としてインタビューされました

  • Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"How an amateur astronomer became one of history's greatest solar observers" Newspaper, magazine

    Atlas Obscura web news, https://www.atlasobscura.com/  2017.11

    　More details

    Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"How an amateur astronomer became one of history's greatest solar observers"

  • NEW STUDY HIGHLIGHTS ‘HIDDEN FIGURE’ OF SUN-WATCHERS

    プレスリリース  2017.10

    　More details

    NEW STUDY HIGHLIGHTS ‘HIDDEN FIGURE’ OF SUN-WATCHERS

  • Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である 「黒点を４０年間記録した故　小山ひさ子さん　太陽観測史上の貴重な貢献」 Newspaper, magazine

    AstroArts web news, http://www.astroarts.co.jp  2017.10

    　More details

    Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である 「黒点を４０年間記録した故　小山ひさ子さん　太陽観測史上の貴重な貢献」

  • Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"Meet Hisako Koyama, Japan's queen of Sunspots" Newspaper, magazine

    Star Stuff web news, https://www.syfy.com  2017.10

    　More details

    Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"Meet Hisako Koyama, Japan's queen of Sunspots"

  • Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"Hisako Koyama was the amateur female astronomer who's earned Galileo Status" Newspaper, magazine

    Curiosity web news, https://curiosity.com  2017.10

    　More details

    Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"Hisako Koyama was the amateur female astronomer who's earned Galileo Status"

  • Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"This Japanese hidden figure enlightened the world with her sunspot sketches" TV or radio program

    アメリカPBS放送局　https://www.pbs.org/news  2017.8

    　More details

    Knipp, Liu, Hayakawa, 2017 Space Weather で発表された小山ひさこに関するのfeature articleをとりあげた新聞記事である。"This Japanese hidden figure enlightened the world with her sunspot sketches"

  • GPS障害の一因解明「大気重力波」

    日刊工業新聞  2017.7

    　More details

    GPS障害の一因解明「大気重力波」

  • Liu et al, 2017 Geophysics. Research Letterで発表された大気重力波の研究をとりあげた新聞記事である：「GPS障害の一因解明」　大気重力波　プラズマバブル発生源の可能性 Newspaper, magazine

    日刊工業新聞  2017.7

    　More details

    Liu et al, 2017 Geophysics. Research Letterで発表された大気重力波の研究をとりあげた新聞記事である：「GPS障害の一因解明」　大気重力波　プラズマバブル発生源の可能性

▼display all

Activities contributing to policy formation, academic promotion, etc.

  • 2023.4 - 2027.3   アメリカ地球物理連合　AGU　 国際測地学・地球物理学連合 (IUGG/IAGA) 日本地球惑星科学連合（JpGU）国際戦略部

    アメリカ地球物理連合（AGU）表彰委員会，国際測地学・地球物理学連合 (IUGG/IAGA)経理委員長，日本地球惑星科学連合（JpGU）国際戦略部委員

  • 2022.4 - 2023.3   アメリカ地球物理連合　AGU　 アメリカ大気圏・電離圏学会（CEDAR） 国際測地学・地球物理学連合 (IUGG/IAGA) 日本地球惑星科学連合（JpGU）国際戦略部

    アメリカ地球物理連合（AGU）国際部アジア代表，アメリカNational Science Foundation傘下の大気圏・電離圏学会（CEDAR）執行部委員，国際測地学・地球物理学連合 (IUGG/IAGA)執行部委員，日本地球惑星科学連合（JpGU）国際戦略部委員

  • 2020.6 - 2023.6   アメリカ　National Science Foundation

    アメリカNational Science Foundation 傘下の大気圏・電離圏学会　CEDAR　の　執行部委員

  • 2019.8 - 2023.8   国際測地学・地球物理学連合IAGA／IUGG

    国際測地学・地球物理学連合　IAGA／IUGG　執行部委員

  • 2018.6 - 2024.6   日本地球惑星科学連合

    日本地球惑星科学連合（JpGU）国際戦略部委員を務めてきた。

  • 2018.1 - 2024.12   アメリカ地球物理連合　AGU

    アメリカ地球物理連合（AGU）国際部アジア代表　（Global Engagement Committee）

▼display all

Acceptance of Foreign Researchers, etc.

  • National Center for Atmospheric Research (NCAR), USA

    Acceptance period： 2024.10 - 2024.11   （Period）：1 month or more

    Nationality：United States

    Business entity：Government agency

  • University of California Berkerley, USA

    Acceptance period： 2024.6   （Period）：1 month or more

    Nationality：United States

    Business entity：Japan Society for the Promotion of Science

  • National Center for Atmospheric Research (NCAR), USA

    Acceptance period： 2024.6   （Period）：1 month or more

    Nationality：United States

    Business entity：Japan Society for the Promotion of Science

  • Chinese academy of Science

    Acceptance period： 2024.2 - 2025.2   （Period）：1 month or more

    Nationality：China

    Business entity：Foreign governments, foreign research institutes, international organizations

  • Chinese academy of Science

    Acceptance period： 2024.2 - 2025.2   （Period）：1 month or more

    Nationality：China

    Business entity：Foreign governments, foreign research institutes, international organizations

  • National Central University, Taiwan

    Acceptance period： 2023.12   （Period）：Less than 2 weeks

    Nationality：United States

    Business entity：Foreign governments, foreign research institutes, international organizations

  • Chinese University of Geology

    Acceptance period： 2023.9 - 2026.10   （Period）：1 month or more

    Nationality：China

    Business entity：Japan Society for the Promotion of Science

  • Institute for Solar-Terrestical Physics, German Aerospace Center (DLR)

    Acceptance period： 2023.9 - 2023.11   （Period）：1 month or more

    Nationality：Germany

    Business entity：Japan Society for the Promotion of Science

  • Institute for Atmosphere Physics (IAP), Rostock University, Germany

    Acceptance period： 2023.9 - 2023.11   （Period）：1 month or more

    Nationality：Germany

    Business entity：Japan Society for the Promotion of Science

  • NASA Goddard Flight Center

    Acceptance period： 2023.1 - 2023.2   （Period）：1 month or more

    Nationality：United States

    Business entity：Japan Society for the Promotion of Science

  • Department of Earth Science, National Cheng-Kung University, Taiwan

    Acceptance period： 2022.11   （Period）：Less than 2 weeks

    Nationality：Taiwan, Province of China

    Business entity：Foreign governments, foreign research institutes, international organizations

  • University of New Brunswick, Canada

    Acceptance period： 2022.10   （Period）：Less than 2 weeks

    Nationality：Canada

    Business entity：Ministry of education

  • National Center for Atmospheric Research (NCAR), USA

    Acceptance period： 2022.9   （Period）：Less than 2 weeks

    Nationality：United States

    Business entity：Japan Society for the Promotion of Science

  • Institute for Atmosphere Physics

    Acceptance period： 2022.9   （Period）：2weeks to less than 1 month

    Nationality：Germany

    Business entity：Government agency

  • Institute for Atmosphere Physics

    Acceptance period： 2022.8 - 2022.10   （Period）：1 month or more

    Nationality：Germany

    Business entity：Government agency

  • IGG, India

    Acceptance period： 2019.5   （Period）：1 month or more

    Nationality：India

    Business entity：Japan Society for the Promotion of Science

  • Chinese Acadamy of Science, China

    Acceptance period： 2019.3 - 2019.8   （Period）：1 month or more

    Nationality：China

    Business entity：Government agency

  • Embry-Riddle Aeronautical University, US

    Acceptance period： 2018.7   （Period）：Less than 2 weeks

    Nationality：United States

    Business entity：On-campus funds

  • University of California, Los Angeles, US

    Acceptance period： 2018.5 - 2018.7   （Period）：1 month or more

    Nationality：United States

    Business entity：Foreign governments, foreign research institutes, international organizations

  • University of Clemson, US

    Acceptance period： 2017.11   （Period）：Less than 2 weeks

    Nationality：Germany

    Business entity：On-campus funds

  • Chinese Acadamy of Science, China

    Acceptance period： 2017.10 - 2019.10   （Period）：1 month or more

    Nationality：China

    Business entity：Foreign governments, foreign research institutes, international organizations

  • MIT, US

    Acceptance period： 2017.5 - 2017.8   （Period）：1 month or more

    Nationality：United States

    Business entity：On-campus funds

  • Canada

    Acceptance period： 2017.3   （Period）：Less than 2 weeks

    Nationality：Canada

    Business entity：Japan Society for the Promotion of Science

  • University of Lancaster, U.K.

    Acceptance period： 2016.10   （Period）：Less than 2 weeks

    Nationality：Japan

    Business entity：Japan Society for the Promotion of Science

  • Institute of Geology and Geophysics, China

    Acceptance period： 2016.8 - 2016.12   （Period）：1 month or more

    Nationality：China

    Business entity：Government agency

  • National Center University, Taiwan

    Acceptance period： 2016.7 - 2017.6   （Period）：1 month or more

    Nationality：Taiwan, Province of China

    Business entity：Government agency

  • Colorado State University, U.S.

    Acceptance period： 2016.4   （Period）：Less than 2 weeks

    Nationality：United States

    Business entity：Government agency

  • Norwegian University of Science and Technology

    Acceptance period： 2016.3   （Period）：Less than 2 weeks

    Nationality：United Kingdom

    Business entity：On-campus funds

  • JAXA

    Acceptance period： 2015.11   （Period）：Less than 2 weeks

    Nationality：Korea, Republic of

    Business entity：On-campus funds

  • National Central University, Taiwan

    Acceptance period： 2015.3   （Period）：Less than 2 weeks

    Nationality：Taiwan, Province of China

    Business entity：Japan Society for the Promotion of Science

  • George Mason University, USA

    Acceptance period： 2015.3   （Period）：Less than 2 weeks

    Nationality：Germany

    Business entity：Japan Society for the Promotion of Science

  • National Central University, Taiwan

    Acceptance period： 2015.2   （Period）：Less than 2 weeks

    Nationality：Taiwan, Province of China

    Business entity：Ministry of education

  • Institute of Geology and Geophysics, Chinese Academy of Science, China

    Acceptance period： 2014.11   （Period）：Less than 2 weeks

    Nationality：China

    Business entity：Japan Society for the Promotion of Science

  • University of New Brunswick, Canada

    Acceptance period： 2014.11   （Period）：Less than 2 weeks

    Nationality：Canada

    Business entity：Ministry of education

  • National Central University, Taiwan

    Acceptance period： 2014.7 - 2014.8   （Period）：1 month or more

    Nationality：Taiwan, Province of China

    Business entity：Government agency

  • National Center for Atmospheric Research (NCAR), USA

    Acceptance period： 2014.7   （Period）：Less than 2 weeks

    Nationality：United States

    Business entity：Japan Society for the Promotion of Science

  • インド地磁気研究所　(Indian Institute of Geomagnetism)

    Acceptance period： 2014.3 - 2013.3   （Period）：Less than 2 weeks

    Nationality：India

    Business entity：On-campus funds

  • 中国科学技術大学

    Acceptance period： 2014.3 - 2013.3   （Period）：Less than 2 weeks

    Nationality：China

    Business entity：On-campus funds

  • University of Oulu, Finland

    Acceptance period： 2014.1   （Period）：Less than 2 weeks

    Nationality：Finland

    Business entity：On-campus funds

  • Faculty of Aerospace Engineering, Delft University of Technology, The Netherlands

    Acceptance period： 2013.10   （Period）：Less than 2 weeks

    Nationality：Netherlands

    Business entity：On-campus funds

  • National Key lab on Space weather, Chinese Academy of Science, China

    Acceptance period： 2013.7 - 2014.7   （Period）：1 month or more

    Nationality：China

    Business entity：Government agency

  • Department of Earth Science, National Cheng-Kung University, Taiwan

    Acceptance period： 2012.10 - 2012.12   （Period）：1 month or more

    Nationality：Taiwan, Province of China

    Business entity：Government agency

  • RISH, Kyoto University

    Acceptance period： 2012.9   （Period）：Less than 2 weeks

    Nationality：India

    Business entity：Japan Society for the Promotion of Science

  • Department of Aerospace Engenering Science, University of Colorado,

    Acceptance period： 2012.7   （Period）：Less than 2 weeks

    Nationality：China

    Business entity：Government agency

  • National Polar Research Institute, China

    Acceptance period： 2012.5 - 2013.4   （Period）：1 month or more

    Nationality：China

    Business entity：Government agency

  • National Center for Atmospheric Research (NCAR)

    Acceptance period： 2012.1   （Period）：Less than 2 weeks

    Nationality：United States

    Business entity：Ministry of education

▼display all

Travel Abroad

  • 2024.9

    Staying countory name 1：Germany   Staying institution name 1：Rostock

  • 2024.7

    Staying countory name 1：United States   Staying institution name 1：Busan

  • 2024.3

    Staying countory name 1：United States   Staying institution name 1：Applied Physics Lab, John Hopkins University

  • 2024.3

    Staying countory name 1：United States   Staying institution name 1：National Science Foundation

  • 2024.3

    Staying countory name 1：United States   Staying institution name 1：NASA Goddard

  • 2023.12

    Staying countory name 1：United States   Staying institution name 1：San Francisco

  • 2023.11

    Staying countory name 1：United States   Staying institution name 1：National Center for Atmosphere Research (NCAR)

  • 2023.7

    Staying countory name 1：Germany   Staying institution name 1：Berlin

  • 2023.6

    Staying countory name 1：United States   Staying institution name 1：San Diego

  • 2023.5 - 2023.6

    Staying countory name 1：Italy   Staying institution name 1：Institute for theoretical physics

  • 2023.3

    Staying countory name 1：United States   Staying institution name 1：NASA Goddard

  • 2022.12

    Staying countory name 1：Germany   Staying institution name 1：Leibniz Institute for Atmosphere Physics

  • 2022.5

    Staying countory name 1：Germany   Staying institution name 1：Leibniz Institute for Atmosphere Physics

  • 2019.12

    Staying countory name 1：China   Staying institution name 1：Tongji University

  • 2019.12

    Staying countory name 1：United States   Staying institution name 1：San Franciso

  • 2019.11

    Staying countory name 1：United States   Staying institution name 1：National Center for Atmosphere Research

  • 2019.8

    Staying countory name 1：China   Staying institution name 1：Tongji University

  • 2019.7

    Staying countory name 1：Canada   Staying institution name 1：Montreal

  • 2019.6

    Staying countory name 1：United States   Staying institution name 1：Washington D.C.

  • 2019.5

    Staying countory name 1：Germany   Staying institution name 1：Institute of Atmosphere Physics

  • 2019.3

    Staying countory name 1：Switzerland   Staying institution name 1：International Space Science Institute

  • 2019.2

    Staying countory name 1：United States   Staying institution name 1：Pasadena/California

  • 2019.1

    Staying countory name 1：China   Staying institution name 1：Institute of Geology and Geophysics, Chinese Academy of Science

  • 2018.12

    Staying countory name 1：United States   Staying institution name 1：Washington D.C.

  • 2018.8 - 2019.3

    Staying countory name 1：United States   Staying institution name 1：National Center for Atmospheric Research

  • 2018.6

    Staying countory name 1：United States   Staying institution name 1：Honolulu

  • 2018.5

    Staying countory name 1：China   Staying institution name 1：University of Science and Technology of China

  • 2018.3

    Staying countory name 1：China   Staying institution name 1：Institute of Geology and Geophysics, Chinese Academy of Science

  • 2017.11

    Staying countory name 1：United States   Staying institution name 1：NASA

  • 2017.8

    Staying countory name 1：Singapore   Staying institution name 1：AOGS2017

  • 2017.5

    Staying countory name 1：Switzerland   Staying institution name 1：International Space Science Institute

  • 2017.3

    Staying countory name 1：Taiwan, Province of China   Staying institution name 1：台湾国立中央大学

  • 2016.12

    Staying countory name 1：United States   Staying institution name 1：AGU2016

  • 2016.10

    Staying countory name 1：United States   Staying institution name 1：NASA living with a star workshop

  • 2016.10

    Staying countory name 1：United States   Staying institution name 1：Colorado

  • 2016.8

    Staying countory name 1：China   Staying institution name 1：Institute of Geology and Geophysics, Chinese Academy of Science

  • 2016.6

    Staying countory name 1：Bulgaria   Staying institution name 1：VarSITI/ SCOSTEP symposium

  • 2016.2

    Staying countory name 1：United States   Staying institution name 1：University of Michigan

  • 2016.1

    Staying countory name 1：Korea, Republic of   Staying institution name 1：KASI

  • 2016.1

    Staying countory name 1：Korea, Republic of   Staying institution name 1：KAIST

  • 2015.12

    Staying countory name 1：United States   Staying institution name 1：AGU2015

  • 2015.12

    Staying countory name 1：Taiwan, Province of China   Staying institution name 1：台湾国立中央大学

  • 2015.8

    Staying countory name 1：Singapore   Staying institution name 1：AOGS2015

  • 2015.8

    Staying countory name 1：China   Staying institution name 1：Institute of Geology and Geophysics, Chinese Academy of Science

  • 2015.6

    Staying countory name 1：United States   Staying institution name 1：University of Washington

  • 2014.12

    Staying countory name 1：Taiwan, Province of China   Staying institution name 1：台湾国立中央大学

  • 2014.11

    Staying countory name 1：Germany   Staying institution name 1：ドイツ地球物理学研究センター(GFZ)

  • 2014.10

    Staying countory name 1：China   Staying institution name 1：Xian University

  • 2014.3 - 2014.4

    Staying countory name 1：Germany   Staying institution name 1：ドイツ地球物理学研究センター(GFZ)

  • 2013.8 - 2013.9

    Staying countory name 1：United States   Staying institution name 1：米国宇宙航空研究開発機構 NASA

  • 2013.7

    Staying countory name 1：Taiwan, Province of China   Staying institution name 1：台湾国立中央大学

  • 2012.9

    Staying countory name 1：China   Staying institution name 1：中国科学院国家空间科学中心　（中国宇宙航空研究開発機構）

  • 2011.12

    Staying countory name 1：United States   Staying institution name 1：San Francisco

  • 2011.8

    Staying countory name 1：Taiwan, Province of China   Staying institution name 1：台湾国立中央大学

  • 2011.7

    Staying countory name 1：Australia   Staying institution name 1：オストラリア　メルボナconvention center

  • 2010.10

    Staying countory name 1：United States   Staying institution name 1：米国国立大気研究センター(NCAR)

  • 2010.7

    Staying countory name 1：Germany   Staying institution name 1：ドイツBremen

  • 2010.7

    Staying countory name 1：Germany   Staying institution name 1：ドイツ地球物理学研究センター(GFZ)

  • 2002.8 - 2005.3

    Staying countory name 1：Germany   Staying institution name 1：ドイツ地球物理研究センター(GFZ)

  • 2001.7 - 2002.7

    Staying countory name 1：United States   Staying institution name 1：米国国立大気研究センター(NCAR)

  • 1998.10 - 2001.4

    Staying countory name 1：Germany   Staying institution name 1：ドイツマックスプランク大気研究所(MPAe)

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