Kyushu University [Huixin Liu (Associate Professor) Faculty of Sciences, Department of Earth and Planetary Sciences]

Department of Earth and Planetary Sciences
Graduate School of Sciences

電磁学

Department of Earth and Planetary Sciences
Graduate School of Sciences

基幹教育セミナー

Department of Earth and Planetary Sciences
School of Sciences

Superheavy element research center

Office for the Promotion of Gender Equality

International Center for Space and Planetary Environmental Science

Other

092-802-4208

Doctor of Science

Yes　Doctor

Space Physics, ionosphere-thermosphere-lower atmosphere coupling, atmospheric dynamics

0000-0001-7073-4366

08years06months

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

Research Interests

Formation machoism of Sporadic E
keyword : vertical coupling, thermosphere, ionosphere,Sporadic E
2021.11～2023.03.
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
2019.03～2023.03.
Response of the upper atmosphere to El Nino Southern Oscillation (ENSO)
keyword : vertical coupling, thermosphere, ionosphere, troposphere, ENSO
2018.04～2023.03.
ENSO effect on the upper atmosphere: the role of O3
keyword : vertical coupling, thermosphere, ionosphere, troposphere, ENSO, Ozone layer
2018.04～2023.03.
Exploring the role of gravity waves in seeding equatorial plasma bubbles
keyword : thermosphere, ionosphere, atmospheric gravity waves, ionospheric irregularities, equatorial plasma bubble
2018.04～2020.03.
Response of the upper atmosphere to El Nino Southern Oscillation (ENSO)
keyword : vertical coupling, thermosphere, ionosphere, troposphere, ENSO
2015.04～2018.03.
Ionospheric Current system observed by the CHAMP satellite
keyword : thermosphere, ionosphere, ionospheric current system
2012.04～2015.03.
Response of the upper atmosphere to stratosphere sudden warming
keyword : vertical coupling, thermosphere, ionosphere, stratosphere
2012.01～2014.08.
Coupling of the Earth's atmospheric layers: interactions between the
ionosphere, thermosphere and mesosphere in the Sun-Earth system
keyword : vertical coupling, thermosphere, ionosphere,
2009.04～2012.03.

Academic Activities

Books

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1.	Goncharenko, L., V. L. Harvey, Huixin Liu, N. Pedatella, 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, Americal Geophysical Union, ISBN:13978-1-119-50755-0, ISBN: 13978-1-119-50755-0, 2021.05.
2.	Huixin Liu, Y. Yamazaki, J. Lei, Space Physics and Aeronomy Collection Volume 4, Upper Atmosphere Dynamics and Energetics, Chapter 15:Day-to-day variability of the thermosphere and ionosphere, Americal Geophysical Union, ISBN:978-1-11950-756-7, ISBN: 978-1-11950-756-7, 2021.05.
3.	Hermann Lühr, Huixin Liu, Jeahueng Park, and Sevim Müller, Aeronomy of the Earth's Atmosphere and Ionosphere: New aspects of the coupling between thermosphere and ionosphere, with special regards to CHAMP mission results, Springer, 303-316, 2011.08.
4.	Claudia Stolle, Huixin Liu, Modeling the Ionosphere-Thermosphere System: Chapter 21:Low-latitude ionosphere and thermosphere: decadal observations from the CHAMP mission, Americal Geophysical Union, doi:10.1002/9781118704417.ch21, 2014.08.
5.	Huixin Liu, Hermann Lühr, W. Koehler, Earth Observation with CHAMP, Springer, Berlin, 2004.12.

Reports

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1.	Larisa P. Goncharenko, V. Lynn Harvey, Huixin Liu, and Nicholas M. Pedatella, Sudden Stratospheric Warming Impacts on the Ionosphere– Thermosphere System: A Review of Recent Progress, アメリカ地球物理連合, DOI: 10.1002/9781119815631.ch15, 2021.05.
2.	Huixin Liu, Y. Yamazaki, J. Lei, Day-to-day variability of the thermosphere and ionosphere, アメリカ地球物理連合, DOI: 10.1002/9781119815631.ch15, 2021.05.
3.	Hapgood, M., Huixin Liu, N. Lugaz, SpaceX-Sailing close to the space weather?, Space Weather, https://doi.org/10.1029/2022SW003074, 2022.03.
4.	Lugaz, N., J. Gannon, M. Hapgood, Huixin Liu, T. Paul O’Brien, Space Weather as the nexus of applied and fundamental space science: the need for separate funding mechanisms and definition, Space Weather, https://doi.org/10.1029/2020SW002695, 2020.12.
5.	Lugaz, N., Huixin Liu, M. Hapgood, S. Morley, Machine-learning research in the Space Weather journal: prospects, scope, and limitations, Space Weather, https://doi.org/10.1029/2021SW003000, 2021.12.
6.	Huixin Liu, J. Thayer, Y. Zhang, W. Lee, The non-storm time corrugated upper thermosphere: What's beyond MSIS?, Space Weather, 10.1002/2017SW001618, 2017.06.
7.	Claudia Stolle, Huixin Liu, CHAMP observations of the low latitude ionosphere and thermosphere and comparisons to physical models, AGU monograph: Modeling the Ionosphere-Thermosphere, 2014.02, [URL].

Papers

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1.	Mike Hapgood, Huixin Liu, Noé Lugaz, SpaceX—Sailing Close to the Space Weather? , Space Weather, 10.1029/2022SW003074, 2022.03.
2.	Yihui Cai, Xinan Yue, Wenbin Wang, Shun‐Rong Zhang, Huixin Liu, Jiuhou Lei, Zhipeng Ren, Yiding Chen, Feng Ding, Dexin Ren, Ionospheric Topside Diffusive Flux and the Formation of Summer Nighttime Ionospheric Electron Density Enhancement Over Millstone Hill , Geophysical Research Letters, 10.1029/2021GL097651, 2022.02.
3.	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, Thermospheric Density Perturbations Produced by Traveling Atmospheric Disturbances During August 2005 Storm , Journal of Geophysical Research: Space Physics, 10.1029/2021JA030071, 2022.02.
4.	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, Superposed epoch analysis of coupling mechanisms captured by meteor radars during sudden stratospheric warmings , DACH, 10.5194/dach2022-84, 2021.12.
5.	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, Long-term changes in mesospheric wind and wave estimates based on radar observations in both hemispheres, DACH, 10.5194/dach2022-81, 2021.12.
6.	Noé Lugaz, Huixin Liu, Mike Hapgood, Steven Morley, Machine‐Learning Research in the Space Weather Journal: Prospects, Scope, and Limitations , Space Weather, 10.1029/2021SW003000, 2021.12.
7.	Qiong Tang, Chen Zhou, Huixin Liu, Yi Liu, Jiaqi Zhao, Zhibin Yu, Zhengyu Zhao, Xueshang Feng, The Possible Role of Turbopause on Sporadic‐E Layer Formation at Middle and Low Latitudes , Space Weather, 10.1029/2021SW002883, 2021.12.
8.	Yihui Cai, Wenbin Wang, Shun‐Rong Zhang, Xinan Yue, Zhipeng Ren, Huixin Liu, Climatology Analysis of the Daytime Topside Ionospheric Diffusive O + Flux Based on Incoherent Scatter Radar Observations at Millstone Hill, Journal of Geophysical Research: Space Physics, 10.1029/2021JA029222, 2021.10.
9.	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, Interhemispheric differences of mesosphere–lower thermosphere winds and tides investigated from three whole-atmosphere models and meteor radar observations, Atmospheric Chemistry and Physics, 10.5194/acp-21-13855-2021, 2021.09.
10.	Masaru Kogure, Huixin Liu, DW1 Tidal Enhancements in the Equatorial MLT During 2015 El Niño: The Relative Role of Tidal Heating and Propagation, Journal of Geophysical Research: Space Physics, 10.1029/2021ja029342, 126, 7, 2021.07, 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..
11.	Masaru Kogure, Jia Yue, Huixin Liu, Gravity Wave Weakening During the 2019 Antarctic Stratospheric Sudden Warming, Geophysical Research Letters, 10.1029/2021GL092537, 48, 8, 2021.04.
12.	Huixin Liu, Yosuke Yamazaki, Jiuhou Lei, Day‐to‐Day Variability of the Thermosphere and Ionosphere, Space Physics and Aeronomy Collection Volume 4: Upper Atmosphere Dynamics and Energetics, Geophysical Monograph 261, 10.1002/9781119815631.ch15, 275-300, 2021.03.
13.	Larisa P. Goncharenko, V. Lynn Harvey, Huixin Liu, Nicholas M. Pedatella, Sudden Stratospheric Warming Impacts on the Ionosphere– Thermosphere System: A Review of Recent Progress, Space Physics and Aeronomy Collection Volume 3: Ionosphere Dynamics and Applications, Geophysical Monograph 260, 10.1002/9781119815617.ch16, 369-400, 2021.03.
14.	Huixin Liu, C. Tao, H. Jin, T. Abe, Geomagnetic activity effects on CO2-driven trend in the thermosphere and ionosphere: ideal model experiments with GAIA, J. Geophys. Res. , 10.1029/2020JA028607, 126, 2021.01.
15.	L. Qiu, X. Zuo, T. Yu, Y. Sun, Huixin Liu, L. Sun, B. Zhao, The characteristics of summer descending sporadic E layer observed with the ionosondes in the China region, J. Geophys. Res. , 10.1029/2020JA028729, 48, 2021.01.
16.	Heikki Vanhamäki, Astrid Maute, Patrick Alken, Huixin Liu, Dipolar elementary current systems for ionospheric current reconstruction at low and middle latitudes, Earth, Planets and Space, 10.1186/s40623-020-01284-1, 72, 1, 2020.12, Abstract 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..
17.	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, First global-scale synoptic imaging of a solar eclipse in the thermosphere, J. Geophys. Res. , 10.1029/2020JA027789, 47, 2020.06.
18.	Yu, T. H. Ye, Huixin Liu, C. Xia, X. Zuo, X. Yan, N. Yang, Y. Sun, B. Zhao, , Ionospheric F-layer scintillation weakening as observed by COSMIC/FORMOSAT-3 during the major sudden stratospheric warming in January 2013, J. Geophys. Res., https://doi.org/10.1029/2019JA027721, 2020.06, [URL].
19.	Kogure, M., Yue J., Huixin Liu, Gravity wave weakening during the 2019 Antarctic stratospheric sudden warming, Geophys. Res. Lett., 10.1029/2021GL092537, 48, 2020.06.
20.	Vanhamaki, H., A. Maute, P. Alken, Huixin Liu, Dipolar elementary current systems for ionospheric current reconstruction at low and middle latitudes, Earth, Planets and Space, https://doi.org/10.1186/s40623-020-01284-1, 72, 2020.06.
21.	Huixin Liu, C. Tao, H. Jin, Y. Nakamoto, Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2-doubling, Geophys. Res. Lett., 10.1029/2020GL087413, 47, 2020.05.
22.	Huixin Liu, Chihiro Tao, Hidekatsu Jin, Yusuke Nakamoto, Circulation and Tides in a Cooler Upper Atmosphere: Dynamical Effects of CO 2 Doubling, Geophysical Research Letters, 10.1029/2020GL087413, 47, 10, 2020.05, 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..
23.	Zhang, R., L. Liu, Huixin Liu, Interhemispheric transport of the ionospheric F region plasma during the 2009 sudden stratosphere warming, Geophys. Res. Lett., 10.1029/2020GL087078, 47, 2020.03.
24.	Hisashi Hayakawa, Frédéric Clette, Toshihiro Horaguchi, Tomoya Iju, Delores J Knipp, Huixin Liu, Takashi Nakajima, Sunspot observations by Hisako Koyama: 1945–1996, 492, 3, 4513-4527, 2020.03.
25.	Hayakawa, H., F. Clette, T. Horaguchi, T. Iju, D. Knipp, Huixin Liu, T. Nakajima, Sunspot observations by Hisako Koyama: 1945-1996, Monthly Notice of Royal Astronomical Society, doi:10.1093/mnras/stz3345, 47, 2020.02.
26.	Yang Yi Sun, Huixin Liu, Yasunobu Miyoshi, Loren C. Chang, Libo Liu, Niño–Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007–2015 FORMOSAT-3/COSMIC observations, earth, planets and space, 10.1186/s40623-019-1009-7, 71, 1, 2019.12.
27.	Libin Weng, Jiuhou Lei, Huixin Liu, Xiankang Dou, Hanxian Fang, Thermospheric Density Cells at High Latitudes as Observed by GOCE Satellite Preliminary Results, Geophysical Research Letters, 10.1029/2019GL084951, 46, 21, 11615-11621, 2019.11.
28.	Zheng Wang, Huixin Liu, Jiankui Shi, Guojun Wang, Xiao Wang, Plasma Blobs Concurrently Observed With Bubbles in the Asian‐Oceanian Sector During Solar Maximum, Journal of Geophysical Research: Space Physics, 10.1029/2018JA026373, 124, 8, 7062-7071, 2019.08, 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..
29.	Tatsuhiro Yokoyama, Hidekatsu Jin, Hiroyuki Shinagawa, Huixin Liu, Seeding of Equatorial Plasma Bubbles by Vertical Neutral Wind, Geophysical Research Letters, 10.1029/2019GL083629, 46, 13, 7088-7095, 2019.07.
30.	Tatsuhiro Yokoyama, Hidekatsu Jin, Hiroyuki Shinagawa, Huixin Liu, Seeding of Equatorial Plasma Bubbles by Vertical Neutral Wind, Geophysical Research Letters, 10.1029/2019GL083629, 46, 13, 7088-7095, 2019.07, 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..
31.	Klemens Hocke, Huixin Liu, Nicholas Pedatella, Guanyi Ma, Global sounding of F region irregularities by COSMIC during a geomagnetic storm, Annales Geophysicae, 10.5194/angeo-37-235-2019, 37, 2, 235-242, 2019.04.
32.	El Nino-Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007-2015 FORMOSAT- 3/COSMIC observations (vol 71, 35, 2019).
33.	A. C. Moral, K. Shiokawa, S. Suzuki, Huixin Liu, Y. Otsuka, C. Y. Yatini, Observations of low-latitude travelling ionospheric disturbances by a 630.0-nm airglow imager and the CHAMP satellite over Indonesia, J. Geophys. Res., https://doi.org/10.1029/2018JA025634, 63, 8, 2623-2637, 2019.03.
34.	Huixin Liu, M. Tsutsumi, Hanli Liu, Vertical structure of terdiurnal tides in the Antarctic MLT region: 15-year observation over Syowa (69S, 39E), Geophys. Res. Lett., 10.1029/2018JA025634, 46, 2019.03.
35.	Huixin Liu, Masaki Tsutsumi, Hanli Liu, Vertical Structure of Terdiurnal Tides in the Antarctic MLT Region 15-Year Observation Over Syowa (69°S, 39°E), Geophysical Research Letters, 10.1029/2019GL082155, 46, 5, 2364-2371, 2019.03.
36.	Nino-Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007-2015 FORMOSAT-3/COSMIC observations.
37.	K. Oyama, C. H. Chen, L. Bankov, D. Minakshi, K. Ryu, J.Y. Liu, Huixin Liu, Precursor effect of March 11 2011 off the coast of Tohoku earthquake on high and low latitude ionospheres and its possible disturbing mechanism, Advances in Space Research, https://doi.org/10.1016/j.asr.2018.12.042, 63, 2019.01.
38.	Zheng Wang, Huixin Liu, Jiankui Shi, Guojun Wang, Xiao Wang, Plasma Blobs Concurrently Observed With Bubbles in the Asian-Oceanian Sector During Solar Maximum, Journal of Geophysical Research: Space Physics, 10.1029/2018JA026373, 2019.01.
39.	Yang Yi Sun, Huixin Liu, Yasunobu Miyoshi, Libo Liu, Loren C. Chang, El Niño–Southern Oscillation effect on quasi-biennial oscillations of temperature diurnal tides in the mesosphere and lower thermosphere, Earth, Planets and Space, 10.1186/s40623-018-0832-6, 70, 1, 2018.12.
40.	M. Nakamura, D. Titov, K. McGouldrick, P. Drossart, J.L. Bertaux, Huixin Liu, Akatsuki at Venus: the first year of scientific operation, Earth, Planets and Space, https://doi.org/10.1186/s40623-018-0916-3, 70, 2018.07.
41.	Run Shi, Binbin Ni, Danny Summers, Huixin Liu, Akimasa Yoshikawa, Beichen Zhang, Generation of Electron Acoustic Waves in the Topside Ionosphere From Coupling With Kinetic Alfven Waves A New Electron Energization Mechanism, Geophysical Research Letters, 10.1029/2018GL077898, 45, 11, 5299-5304, 2018.06.
42.	Y. Yamazaki, C. Stolle, J. Matzka, Huixin Liu, C. Tao, Interannual Variability of the Daytime Equatorial Ionospheric Electric Field, Journal of Geophysical Research: Space Physics, 10.1002/2017JA025165, 123, 2018.05.
43.	S. Eswaraiah, Yong Ha Kim, Huixin Liu, M. Venkat Ratnam, Jaewook Lee, 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, Earth, Planets and Space, 10.1186/s40623-017-0704-5, 69, 1, 2017.12.
44.	Delores Knipp, Huixin Liu, Hisashi Hayakawa, Ms. Hisako Koyama:From Amateur Astronomer to Long-Term Solar Observer, Space Weather, 10.1002/2017SW001704, 15, 10, 1215-1221, 2017.10.
45.	P. Abadi, Y. Otsuka, K. Shiokawa, A. Husin, Huixin Liu, S. Saito, Equinoctial asymmetry in the zonal distribution of scintillation as observed by GPS receivers in Indonesia, Journal of Geophysical Research, 10.1002/2017JA024146, 122, 8, 8947-8958, 2017.08.
46.	Huixin Liu, Nicholas Pedatella, Klemens Hocke, Medium-scale gravity wave activity in the bottomside F region in tropical regions, Geophysical Research Letters, 10.1002/2017GL073855, 44, 14, 7099-7105, 2017.07.
47.	Huixin Liu, Jeff Thayer, Yongliang Zhang, Woo Kyoung Lee, The non–storm time corrugated upper thermosphere What is beyond MSIS?, Space Weather, 10.1002/2017SW001618, 15, 6, 746-760, 2017.06.
48.	N. S.A. Hamid, Huixin Liu, T. Uozumi, Akimasa Yoshikawa, N. M.N. Annadurai, Peak time of equatorial electrojet from different longitude sectors during fall solar minimum, Journal of Physics: Conference Series, 10.1088/1742-6596/852/1/012015, 852, 1, 2017.06.
49.	Liu Huixin, Y. Sun, Yasunobu Miyoshi, H. Jin, ENSO effects on MLT diurnal tides: A 21 year reanalysis data-driven GAIA model simulation, J. Geophys. Res, 10.1002/2017JA024011, 122, 2017.05.
50.	L. Liu, Liu Huixin, H. Le, Y. Chen, Y. Sun, B. Ning, L. Hu, W. Wan, N. Li, J. Xiong, Mesospheric temperatures estimated from the meteor radar observations at Mohe, China, J. Geophys. Res, 10.1002/2016JA023776, 122, 2017.03.
51.	Y. Yamazaki, Liu Huixin, Y. Sun, Yasunobu Miyoshi, M. Kosch, M. Mlynczak, Quasi-biennial oscillation of the ionospheric wind dynamo, J. Geophys. Res, 10.1002/2016JA023684, 122, 2017.03.
52.	L. Liu, Liu Huixin, Y. Chen, H. Le, Y. Sun, B. Ning, L. Hu, W. Wan, Variations of the meteor echo heights at Beijing and Mohe, J. Geophys. Res, 10.1002/ 2016JA023448, 122, 2017.01.
53.	J. Guo, F. Wei, X. Feng, J. Forbes, Y. Wang, Liu Huixin, W. Wan, Prolonged multiple excitation of large-scale traveling atmospheric disturbances (TADs) by successive and interacting coronal mass ejections, J. Geophys. Res, 10.1002/2015JA022076, 2016.07.
54.	Liu Huixin, E. Doornbos, J. Nakashima, Thermospheric wind observed by GOCE: wind jets and seasonal variations, J. Geophys. Res, 10.1002/2016JA022938, 121, 2016.06.
55.	Jianpeng Guo, F. Wei, Xueshang Feng, Liu Huixin, Weixing Wan, et. al, Alfvén waves as a solar-interplanetary driver of the thermospheric disturbances, Scientific Reports, 10.1038/srep-18895, 2016.05.
56.	K. Ryu, K. Oyama, L. Bankov, C. Chen, M. Devi, Liu Huixin, J. Liu, Precursory enhancement of EIA in the morning sector: contribution from Mid-latitude large earthquake in the north-east Asian region, Adv. in Space. Res, http://dx.doi.org/10.1016/j.asr.2015.08.030, 2016.05.
57.	K. Oyama, M. Devi, K. Ryu, C. Chen, J. Liu, Liu Huixin, L. Bankov, Modifications of the ionosphere prior to large earthquakes: report from the ionosphere precursor study group, Geoscience Letter, doi:10.1186/s40562-016-0038-3, 2016.05.
58.	Liu Huixin, Thermospheric inter-annual variability and its potential connection to ENSO and stratospheric QBO, Earth. Planets and Space, 10.1186/s40623-016-0455-8, 2016.04.
59.	Jianpeng Guo, J. Forbes, F. Wei, Xueshang Feng, Liu Huixin, Weixing Wan, et. al, Observations of a large-scale gravity wave propagating over an extremely large horizontal distance in the thermosphere, Geophys. Res. Lett., 10.1002/2015GL065671, 42, 2015.08.
60.	Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto, Empirical model of equatorial electrojet based on ground-based magnetometer data during solar minimum in fall, Earth. Planets and Space, 10.1186/s40623-015-0373-1, 67, 2015.06.
61.	Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto, Longitudinal and Solar Activity Dependence of Equatorial Electrojet At Southeast Asian Sector, IEEE, 262-266, 2015.06.
62.	L. Chang, Liu Huixin, Yasunobu Miyoshi, C. Chen, F. Chang, C. Lin, J. Y. Liu, Y. Y. Sun, Structure and origins of the Weddell Sea Anomaly from tidal and planetary wave signatures in FORMOSAT-3/COSMIC observations and GAIA GCM simulations, J. Geophys. Res., doi:10.1002/2014JA020752, 120, 1325-1340, 2015.02.
63.	K.-I. Oyama, J. T. Jhou, J. T. Lin, C. Lin, Liu Huixin, Kiyohumi Yumoto, Ionospheric response to 2009 Sudden Stratospheric Warming in the northern hemisphere, J. Geophys. Res., 10.1002/2014JA020014, 119, 1-16, 2014.11.
64.	Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto, Relationship between equatorial electrojet and global Sq currents at dip equator region, Earth, Planets and Space, http://www.earth-planets-space.com/content/66/1/146, 66, 1-11, 2014.10.
65.	C. Lin, J. T. Lin, C.H. Chen, J. Y. Liu, Y. Y. Sun, Y. Kakinam, M. Matsumura, Liu Huixin, R. J. Rau, Ionospheric shock waves triggered by rockets, Ann. Geophys., 10.5194/angeo-32-1145-2014, 32, 1145-1152, 2014.09.
66.	Jianpeng Guo, Liu Huixin, Xueshang Feng, Weixing Wan, Yue Deng, Chaoxu Liu, Constructive interference of large-scale gravity waves excited by interplanetary shock on 29 October 2003: CHAMP observation, J. Geophys. Res., 10.1002/2014JA020255, 119, 1-6, 2014.08.
67.	Liu Huixin, Yasunobu Miyoshi, Saburo Miyahara, H. Jin, H. Fujiwara, H. Shinagawa, Thermal and dynamical changes of the zonal mean state of the thermosphere during the 2009 SSW: GAIA simulations, J. Geophys. Res., 10.1002/2014JA020222, 119, 1-7, 2014.08.
68.	M. G. 4. Cardinal, Yoshikawa Akimasa, Huixin Liu, Masakazu Watanabe, Kiyohumi Yumoto, Hideaki Kawano, Capacity building: A tool for advancing space weather science, Space Weather, 10.1002/2014SW001110, 12, 2014.08.
69.	Jianpeng Guo, Liu Huixin, Xueshang Feng, T. I. Pulkkinen, E. I. Tanskanen, Chaoxu Liu, Dingkun Zhong, Yuan Wang, MLT and seasonal dependence of auroral electrojets: IMAGE magnetometer network observations, J. Geophys. Res., 10.1002/2014JA019843, 119, ?-?, 2014.04.
70.	Jianpeng Guo, T. I. Pulkkinen, E. I. Tanskanen, Xueshang Feng, Barbara A. Emery, Liu Huixin, Chaoxu Liu, Dingkun Zhong, Annual variations in westward auroral electrojet and substorm occurrence rate during solar cycle 23, J. Geophys. Res., 10.1002/2013JA019742, 119, ?-?, 2014.03.
71.	Claudia Stolle, Huixin Liu, CHAMP observations of the low latitude ionosphere and thermosphere and comparisons to physical models, AGU monograph: Modeling the Ionosphere-Thermosphere, 201, ?-?, 2014.02.
72.	Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto, Equatorial electrojet dependence on solar activity in the Southeast Asia sector, Antarctic Record, 57, 3, 329-337, 2013.12.
73.	Hongru Chen, Liu Huixin, Toshiya Hanada, Storm-time atmospheric density modeling using neural networks and its application in orbit propagation, Adv. in Space Research, 10.1016/j.asr.2013.11.052, 53, 558-567, 2013.12.
74.	Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto, Brief Study of Equatorial Electrojet and Global Sq Currents At Southeast Asia Region, IEEE International Conference on Space Science and Communication (IconSpace), 1-3 July 2013, 194-197, 2013.07.
75.	Huixin Liu, H. Jin, Yasunobu Miyoshi, H. Fujiwara, H. Shinagawa, Upper atmosphere response to stratosphere sudden warming: Local time and height dependence simulated by GAIA model, Geophys. Res. Lett., 10.1002/grl.50146, 40, 635-640, 2013.02.
76.	Huixin Liu, T. Hirano, S. Watanabe, Empirical model of the thermospheric mass density based on CHAMP satellite observations, J. Geophys. Res., doi:10.1002/jgra.50144, 118, 843-848, 2013.02.
77.	R. Shi, Huixin Liu, Akimasa Yoshikawa, Beichen Zhang, Binbin Ni, Coupling of electrons and inertial Alfven waves in the topside ionosphere, J. Geophys. Res. , doi:10.1002/jgra.50355, 118, 843-848, 2013.02.
78.	Y. Yamazaki, A. D. Richmond, Liu Huixin, Kiyohumi Yumoto, Y. Tanaka, Sq current system during stratospheric sudden warming events in 2006 and 2009, J. Geophys. Res. , 10.1029/2012JA018116, 117, 2012.12.
79.	Jusoh M. H., Kiyohumi Yumoto, Abdul Hamid N. S., Huixin Liu, Electromagnetic Coupling on Solar-Terrestrial System: Possible effects on seismic activities, Proceedings of ISAP2012, 1160-1163, 2012.11.
80.	S. Tulasi Ram, N. Balan, B. Veenadhari, S. Gurubaran, S. Ravindran, T. Tsugawa, Liu Huixin, K. Niranjan, T. Nagatsuma, First observational evidence for opposite zonal electric fields in equatorial E and F region altitudes during a geomagnetic storm period, J. Geophys. Res. , 10.1029/2012JA018045, 118, 2012.09.
81.	Y. Miyoshi, H. Fujiwara, H. Jin, H. Shinagawa, Huixin Liu, Numerical simulation of the equatorial wind jet in the thermosphere, J. Geophys. Res. , 10.1029/2011JA017373, 117, 2012.03.
82.	Yasunobu Miyoshi, H. Jin, H. Fujiwara, H. Shinagawa, Huixin Liu, Wave-4 structure of the neutral density in the thermosphere and its relation to atmospheric tides, J. Atmos. Solar-Terres. Phys.,, 10.1016/j.jastp.2011.12.002, 90, 45-51, 2012.01.
83.	Lühr, H., Huixin Liu, J. Park, S. Muller, , New Aspects of the Coupling Between Thermosphere and Ionosphere, with Special regards to CHAMP Mission Results, IAGA Special Sopron Book Series, 10.1007/978-94-007-0326-1_22, 2011.10.
84.	Liu Huixin, M. Yamamoto, E. Doornbos, Equatorial Electrodynamics and Neutral Background in the Asian Sector During the 2009 Stratospheric Sudden Warming, J. Geophys. Res. , 10.1029/2011JA016607, 116, 2011.08.
85.	N. Balan, M. Yamamoto, J. Y. Liu, Y. Otsuka, Huixin Liu, and H. Lühr, New aspects of thermospheric and ionospheric storms revealed by CHAMP, J. Geophys. Res., 10.1029/2010JA016399, 116, 2011.07.
86.	Lühr, H. J. Park, P. Ritter, Huixin Liu, In-situ CHAMP observations of the ionosphere-thermosphere coupling, Space Sci. Rev., 10.1007/s11214-011-9798-4, 2011.07.
87.	Huixin Liu, E. Doornbos, M. Yamamoto, S. T. Ram, Strong thermosphere cooling during the 2009 major statratosphere warming, Geophys. Res. Lett, 10.1029/2011GL047898, 38, 2011.06.
88.	Huixin Liu, M. Yamamoto, Weakening of the mid-latitude summer night anomaly during geomagnetic storms, Earth. Planets and Space, 63, 371-375, 2011.06.
89.	S. Tulasi Ram, M. Yamamoto, Huixin Liu, B. Veenadhari, S. Alex, 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., J. Geophys. Res., 10.1029/2010JA016634, 116, 2011.06.
90.	S. V. Thampi, M. Yamamoto, C. Lin, Huixin Liu, Comparison of FORMOSAT‐3/COSMIC radio occultation measurements with radio tomography, Radio Science, 10.1029/2010RS004431, 46, 2011.05.
91.	Y. Miyoshi, H. Fujiwara, H. Jin, H. Shinagawa, Huixin Liu, and K. Terada, Model study on the formation of the equatorial mass density anomaly in the thermosphere, J. Geophys. Res., 10.1029/2010JA016315, 116, 2011.05.
92.	T. Kondo, A. D. Richmond, Huixin Liu, J. Lei, S. Watanabe, On the formation of a fast thermospheric zonal wind at the magnetic dip equator, Geophys. Res. Lett., 10.1029/2011GL047255, 38, 2011.05.
93.	C. Stolle, Huixin Liu, V. Truhlík, H. Lühr, P. G. Richards, Solar flux variation of the electron temperature morning overshoot in the equatorial F region, J. Geophys. Res., 10.1029/2010JA016235, 116, 2011.04.
94.	Thampi, S. V., N. Balan, C. Lin, Liu Huixin, M. Yamamoto, Mid-latitude summer nighttime anomaly (MSNA) – observations and model simulations, Ann. Geophys., , 29, 157, 165, 157-165, 2011.04.
95.	Adachi, T., M. Yamaoka, M. Yamamoto, Y. Otsuka, Liu Huixin, C. Hsiao, A. Chen, R. Hsu, Midnight latitude-altitude distribution of 630-nm airglow in the Asian sector measured with Formosat-2/ISUAL, J. Geophys. Res, 10.1029/2009JA015147, 115, A09315, 2010.07.
96.	Thampi, S. V., M. Yamamoto, Liu Huixin, S. Saito, Y. Otsuka, A. K. Patra, Nighttime-like Quasi Periodic echoes induced by a partial solar eclipse, Geophys. Res. Lett., 10.1029/2010GL042855, 37, L09107, 2010.07.
97.	Liu Huixin, Thampi, S. V., M. Yamamoto, Phase reversal of the diurnal cycle in the mid-latitude ionosphere, J. Geophys. Res, 10.1029/2009JA014689, 115, A01305, 2010.06.
98.	Thampi, S. V., C. Lin, Liu Huixin, M. Yamamoto, First Tomographic Observations of the Mid-latitude Summer Nighttime Anomaly (MSNA) over Japan, J. Geophys. Res. , 10.1029/2009JA014439, 114, A10318, 2009.07.
99.	Liu Huixin, M. Yamamoto, H. Luehr, Wave-4 pattern of the equatorial mass density anomaly- A thermospheric signature of tropical deep convection, Geophys. Res. Lett., 10.1029/2009GL039865, 36, L18104, 2009.06.
100.	Liu Huixin, H. Luehr, S. Watanabe, A solar terminator wave in thermospheric wind and density simultaneously observed by CHAMP, Geophys. Res. Lett., 10.1029/2009GL038165, 36, L10109, 2009.05.
101.	Liu Huixin, S. Watanabe, T. Kondo, Fast thermospheric wind jet at the Earth's dip equator, Geophys. Res. Lett., 10.1029/2009GL037377, 36, L08103, 2009.03.
102.	Liu Huixin, S. Watanabe, Seasonal variation in the longitudinal structure of the equatorial ionosphere: does it reflect tidal influences from below? , J. Geophys. Res. , 10.1029/2008JA013027, 113, A08315, 2008.01.
103.	Liu Huixin, H. Luehr, S. Watanabe, W. Koehler, M. Manoj, Contrasting behavior of the thermosphere and ionosphere to the Oct. 28, 2003 solar flare, J. Geophys. Res., 10.1029/2007JA012313, 112, A07305, 2007.05.
104.	Liu Huixin, H. Luehr, S. Watanabe, V. Henize, W. Koehler, P. Visser, Zonal winds in the equatorial upper thermosphere: Decomposing the solar flux, geomagnetic activity, and seasonal dependencies, J. Geophys. Res., 10.1029/2005JA011415, 111, A07307, 2007.05.
105.	Liu Huixin, C. Claudia, M. Forster, S. Watanabe, Solar activity dependence of the electron density at 400 km at equatorial and low latitudes observed by CHAMP, J. Geophys. Res., 10.1029/2007JA012616, 112, A11311, 2007.03.
106.	Liu Huixin, C. Claudia, S. Watanabe, T. Abe, D. Cooke, Evaluation of the IRI Model Using CHAMP Observations in Polar and Equatorial Regions, Adv. in Space. Res., , 39, 904-909, 2007.03.
107.	Liu Huixin, H. Luehr, S. Watanabe, Climatology of the Equatorial Thermospheric Mass Density Anomaly, J. Geophys. Res., 10.1029/2006JA012199, 112, A05305, 2007.01.
108.	Liu Huixin, H. Luehr, Strong disturbance of the upper thermospheric density due to magnetic storms: CHAMP observations, J. Geophys. Res., 10.1029/2004JA010908, 110, A09S29, 2005.10.
109.	Liu Huixin, H. Luehr, V. Henize, W. Koehler, Global distribution of the thermospheric total mass density derived from CHAMP, J. Geophys. Res., 10.1029/2004JA010741, 110, A04301, 2005.05.
110.	Liu Huixin, G. Lu, Velocity shear-related ion upflows in the low-altitude ionosphere, Ann. Geophysics., 22, 1149-1153, 2004.10.
111.	Liu Huixin, S. Y. Ma, K. Schlegel, Diurnal, seasonal, and geomagnetic variations of large field-aligned ion upflows in the high-latitude ionospheric F region, J. Geophys. Res, 106, 24,651-24,662, 2001.06.
112.	Liu Huixin, K. Schlegel, S. Y. Ma, Combined ESR and EISCAT observations of the dayside polar cap and auroral oval during the May 15, 1997 storm, Ann. Geophysics., 18, 1067-1072, 2000.10.

Presentations

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1.	Huixin　Liu, The atmosphere-ionosphere coupling and space weather, ドイツDFG基金会特別推進プログラムSPPシンポジウム, 2021.06.
2.	M. Kogure Huixin　Liu, Gravity wave weakening during the 2019 Antarctic stratospheric sudden warming, JpGU 2021, 2021.05.
3.	Huixin　Liu, Geomagnetic activity effects on CO2-driven trend in the ionosphere: GAIA experiments, European Geophysical Union 2021, 2021.04.
4.	Liu Huixin, C. Tao, H. Jin, Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2 doubling, COSPAR, 2021.01.
5.	Huixin　Liu, The Earth's upper atmosphere and space weather, JpGU２０20, 2020.07, 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。.
6.	Liu Huixin, AGU FAIR data policy and author guideline, SGEPSS2020　（日本電磁気・惑星学会）, 2020.11.
7.	Liu Huixin, C. Tao, H. Jin, Circulation and tides in a cooler upper atmosphere: dynamical effects of CO2 doubling, JpGU２０20, 2020.07, 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.
8.	Huixin Liu, C. Tao., H. Jin, T. Abe, Dynamical response of the upper atmosphere to CO2 doubling: GAIA simulation, AGU2019, 2019.12.
9.	Huixin Liu, M. Tsutsumi, H. Liu, Vertical structure of terdiurnal tides in the Antarctic MLT region: 15-year observation over Syowa (69S, 39E), SGEPSS2019, 2019.10.
10.	Huixin Liu, M. Tsutsumi, H. Liu, Vertical structure of terdiurnal tides in the Antarctic MLT region: 15-year observation over Syowa (69S, 39E), IUGG2019, 2019.07.
11.	Liu Huixin, Y. Sun, Y. Miyoshi, H. Jin, ENSO effects on MLT diurnal tides: a 21-year reanalysis-drive GAIA model simulation, JpGU２０１９, 2019.05.
12.	Liu Huixin, Y. Sun, Y. Miyoshi, H. Jin, ENSO effects on MLT diurnal tides: a 21-year reanalysis-drive GAIA model simulation, AOGS2018, 2018.06.
13.	Liu Huixin, 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), JpGU meeting 2018, international session, 2018.05, 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..
14.	Liu Huixin, Y. Nakamoto, Y. Miyoshi, Thermosphere response to CO2 doubling: GAIA simulation results, 10th international workshop on Long-term trends, 2018.05.
15.	Liu Huixin, Role of Medium-scale GW in seeding plasma bubbles, NIPR symposium 2017, 2017.12.
16.	Liu Huixin, Medium-scale GW activity in bottomside F region , SGEPSS 2017, 2017.10.
17.	Liu Huixin, Y. Nakamoto, Y. Miyoshi, Thermosphere response to CO2 doubling: GAIA simulation results, AOGS2017, 2017.08.
18.	Liu Huixin, Y. Sun, Y. Miyoshi, H. Jin, ENSO effects on MLT diurnal tides: a 21-year reanalysis-drive GAIA model simulation, AGU-JpGU joint meeting 2017, 2017.05.
19.	Liu Huixin, Thermosphere interannual variability: potential fingerprints of QBO and ENSO, JAXA symposium, 2016.12, Interannual variation of the upper atmosphere.
20.	Liu Huixin, Thermosphere interannual variability: implications for ENSO and QBO, The International Whole Atmospherear Symposium, 2016.09.
21.	Liu Huixin, Thermosphere interannual variability: ENSO effects, Mesosphere-Thermosphere-ionosphere workshop, 2016.08.
22.	Liu Huixin, Thermosphere and Ionosphere response to solar flares, VarSITI/ SCOSTEP symposium, 2016.06, This invited talk summarize the thermosphere and ionosphere response to solar flares, and emphasize recent progresses made by satellite observations..
23.	Liu Huixin, Thermosphere response to stratosphere sudden warming simulated by GAIA, ISEA2015, 2015.10.
24.	K. Oyama, K. Ryu, Liu Huixin, Earthquake Ionosphere Precursor Study Group and Its Role - Toward Strengthening Earthquake Study, AOGS2015, 2015.08.
25.	K. Oyama, K. Ryu, Liu Huixin, Diversity of Ionosphere Modification Possibly Caused by Large Earthquakes, AOGS2015, 2015.08.
26.	K. Ryu, K. Oyama, Liu Huixin, Contribution of the Mid-Latitude Seismic Activity to the EIA Intensity Variation Suggested by Satellite Electron Density Measurements, AOGS2015, 2015.08.
27.	L. Chang, Liu Huixin, Yasunobu Miyoshi, Structure and Origins of the Weddell Sea Anomaly From Tidal and Planetary Wave Signatures in FORMOSAT-3/COSMIC Observations and GAIA GCM Simulations, AOGS2015, 2015.08.
28.	N. S. A. Hamid, Liu Huixin, EEJ Empirical Model Based on Ground-Based Magnetometer Data, AOGS2015, 2015.08.
29.	Liu Huixin, Periodic Variations in the Thermospheric Density, AOGS2015, 2015.08.
30.	Liu Huixin, Thermosphere responses to SSWs simulated by GAIA model, CEDAR 2015, 2015.06.
31.	CHIEN, Shin han, CHANG, Loren, Liu Huixin, Variability of the Equatorial Ionization Anomaly on seasonal and day to day time scales, JpGU meeting 2015, international session, 2015.05.
32.	Liu Huixin, Periodic variations in the thermospheric density, JpGU meeting 2015, international session, 2015.05.
33.	Liu Huixin, Thermal and dynamical response of the thermosphere to stratosphere sudden warming, SCOSTEP 2014, 2014.10.
34.	Liu Huixin, Upper atmosphere response to stratosphere sudden warming events, SCOSTEP, 2014.10.
35.	G. Maeda, Kiyohumi Yumoto, Liu Huixin, Current Status of the MAGDAS Project - The Largest Magnetometer Array in the World, AOGS2014, 2014.08.
36.	J. Jhou, Y. Oyama, C. Lin, Liu Huixin, Ionospheric Response to 2009 Sudden Stratosphere Warming in the Northern and Southern Hemisphere, AOGS2014, 2014.07.
37.	M. Förster, Liu Huixin, C. Stolle, Solar Activity and Seasonal Effects of the Upper Atmosphere at High Latitudes According to Observations and Modelling, AOGS2014, 2014.07.
38.	Shin Suzuki, J. Park, Y. Otsuka, Liu Huixin, H. Luehr, Coordinated Measurements of Medium-scale Traveling Ionospheric Disturbances with Ground-based Airglow Imagers and CHAMP Satellite, AOGS2014, 2014.07.
39.	N. S. A. Hamid, Liu Huixin, Local Time and Longitudinal Dependence of Equatorial Electrojet Calculated from Ground-based Magnetometer, AOGS2014, 2014.07.
40.	Liu Huixin, Thermosphere Cooling at Low and Middle Latitudes During Stratosphere Warming Events: GAIA Model Simulations, AOGS2014, 2014.07.
41.	Rinako TAKAZAKI, Liu Huixin, Saburo Miyahara, The Ionospheric Sq Current Systems Influenced by Semidiurnal Tide During Sudden Stratospheric Warming Events Simulated by the Kyushu-GCM, AOGS2014, 2014.07.
42.	Guo Jianpeng, Liu Huixin, MLT and seasonal dependence of auroral electrojets: IMAGE magnetometer network observations, JpGU meeting 2014, international session, 2014.05.
43.	Liu Huixin, Hermann Luehr, Enhancing our understanding of the atmosphere-ionosphere coupling with Low Earth Orbiting satellite missions, JpGU meeting 2014, international session, 2014.04.
44.	Liu Huixin, Global mean cooling of the thermosphere during the 2009 major SSW, Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium, 2013.11.
45.	Liu Huixin, Deguchi Ryo, Ionospheric current system derived from CHAMP using DECS method at low and middle latitudes, Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium, 2013.11.
46.	Liu Huixin, Nurul Shazana Abdul Hamid, The equatorial electrojet and global Sq current components at dip equator, Scientific committee on Solar-Terrestrial Physics: Internatinoal CAWSES-II symposium, 2013.11.
47.	Liu Huixin, vertical coupling processes in the Earth's system, NASA review panel, 2013.08.
48.	Liu Huixin, Thermosphere response to lower atmosphere forcing: decadal observations from the CHAMP mission, Workshop on Whole Atmosphere Coupling During Solar Cycle 24 , 2013.07.
49.	Nurul Shazana Abdul Hamid, Liu Huixin, Brief Study of Equatorial Electrojet and Global Sq Currents At Southeast Asia Region, IEEE International Conference on Space Science and Communication (IconSpace), 2013.07.
50.	N. A. A. Hamid, Liu Huixin, Kiyohumi Yumoto, Relation Between the Local Equatorial Electrojet and Global Sq Current Calculated from Different Longitude Sectors, AOGS2013, 2013.06.
51.	Nurul Shazana Abdul Hamid, Liu Huixin, Relation Between the Local Equatorial Electrojet and Global Sq Current Calculated from Different Longitude Sectors, Asia Oceania Geosciences Society, 2013.06.
52.	Liu Huixin, Upper atmosphere response to stratosphere sudden warming: local time and height dependence simulated by GAIA model, JpGU meeting 2013, international session, 2013.05.
53.	Liu Huixin, Mohamad Huzaimy Bin Jusoh, Possible relationship between Solar Wind Input Energy and Seismicity, JpGU meeting 2013, international session, 2013.05.
54.	Nurul Shazana Abdul Hamid, Liu Huixin, Relation between the local equatorial electrojet and global Sq current calculated from different longitude sectors, JpGU meeting 2013, international session, 2013.05.
55.	Deguchi Ryo, Liu Huixin, Modification of one-dimensional spherical elementary current systems for applying at low/mid latitude, JpGU meeting 2013, international session, 2013.05.
56.	Jusoh Mohamad Huzaimy, Liu Huixin, Yumoto Kiyohumi, Investigation on the Possible Relationship between Magnetic Pulsations and Earthquakes, AGU fall meeting 2012, 2012.12.
57.	Liu Huixin, Upper thermosphere coupling with the lower atmosphere: the known and unknown, 地球電磁気・地球惑星圏学会, 2012.11.
58.	Jusoh Mohamad Huzaimy, Liu Huixin, Yumoto Kiyohumi, Exploration of the Possible Relationship between Magnetic Pulsations and Earthquakes, 地球電磁気・地球惑星圏学会, 2012.11.
59.	Shi Run, Liu Huixin, Yoshikawa Akimasa, 1D simulation of Electron acceleration by Inertial Alfven wave pulse, 地球電磁気・地球惑星圏学会, 2012.11.
60.	Liu Huixin, Jin, H, Miyoshi Yasunobu, Fujiwara Hitoshi, Shinagawa, H., GAIA model simulation of the thermosphere response to SSW, 地球電磁気・地球惑星圏学会, 2012.11.
61.	ABDUL HAMID NURUL SHAZANA, Liu Huixin, Relation between the local equatorial electrojet and global Sq current system, 地球電磁気・地球惑星圏学会, 2012.11.
62.	Liu Huixin, Upper atmosphere response to major and minor stratosphere sudden warming, ISEA13, 2012.03.
63.	Liu Huixin, Equatorial electrodynamics and neutral background in the Asian sector during the 2009 Stratosphere sudden warming , AOGS, 2011.08.
64.	Liu Huixin, Upper-lower atmosphere coupling: known and unknowns, IUGG 2011 General Assembly, 2011.07.

Membership in Academic Society

SGEPSS
JAPAN GEOSCIENCE UNION
American Geophysical Union
European Geophysical Union
AOGS
Japan Meteorogical Society
Japan Geophysical Union
Asia Oceania Geophysical Society
European Geophysical Union
American Geophysical Union
Society of Geomagnetism and Earth, Planetary and Space Science

Awards

DAAD Fellowship for academic exchange
Alexander von Humboldt Fellowship
JSPS fellow (foreign)
RPD Fellow
Obayashi Medal for distinguished young scientist
Japan MEXT distinguished young scientist award
Shiseido Science Grant
JpGU Nishida Award
Research on the vertical coupling between the atmosphere and ionosphere using high-precision satellite observations and whole atmosphere models
Research on the thermosphere-ionosphere interaction using satellite-bourne accelerometer observations
Plasma-neutral interaction in the mesosphere-thermosphere-ionosphere system
The Thermosphere-Ionosphere Coupling at Low Latitudes
Global Thermosphere-Ionosphere coupling study base on CHAMP satellite observations
Studying the polar ionosphere response to magnetic storms with the international EISCAR radar system

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

Other Educational Activities

2020.11.

Professional and Outreach Activities

Formation of Preliminary Center for Capacity Building for Space Weather Research. JSPS Core-to-Core Program, 2012 ISWI and MAGDAS School on Space Science。
Two International collaboration projects with NCAR, US (2018-2022) and Germany (Leipzip University, IAP) and Swiss (University of Bern) (2019-2023)..

https://kyushu-u.pure.elsevier.com/en/persons/huixin-liu Reseacher Profiling Tool Kyushu University Pure

https://kyushu-u.pure.elsevier.com/en/persons/huixin-liu
　Reseacher Profiling Tool　Kyushu University Pure