| 1. |
H.Shinagawa and Y.Miyoshi, Simulation study of atmosphere–ionosphere variations driven by the eruption of Hunga Tonga-Hunga Ha’apai on 15 January 2022, Earth, Planets and Space, https://doi.org/10.1186/s40623-024-01960-6, 76, 2024.01. |
| 2. |
Yamazaki, Y., Harding, B. J., Qiu, L., Stolle, C., Siddiqui, T. A., Miyoshi, Y., Monthly climatologies of zonal-mean and tidal winds in the thermosphere as observed by ICON/ MIGHTI during April 2020–March 2022, Earth and Space Science, https://doi. org/10.1029/2023EA002962, 10, 2023.06. |
| 3. |
Qiu, L., Yamazaki, Y., Yu, T., Becker, E., Miyoshi, Y., Qi, Y., et al. , Numerical simulations of metallic ion density perturbations in sporadic E layers caused by gravity waves, Earth and Space Science, https://doi.org/10.1029/2023EA003030, 10, 2023.08. |
| 4. |
Günzkofer, F., Stober, G., Pokhotelov, D., Miyoshi, Y., and Borries, C., Difference spectrum fitting of the ion–neutral collision frequency from dual-frequency EISCAT measurements, Atmos. Meas. Tech., https://doi.org/10.5194/amt-16-5897-2023, 16, 5897-5907, 2023.12. |
| 5. |
Y. Miyoshi and H.Shinagawa, Upward propagation of gravity waves and ionospheric perturbations triggered by the 2022 Hunga-Tonga volcanic eruption, Earth, Planets and Space, https://doi.org/10.1186/s40623-023-01827-2, 75, 2023.05. |
| 6. |
S. Sobhkhiz-Miandehi, Y. Yamazaki, C. Arras, and Y. Miyoshi and H.Shinagawa, Comparison of the tidal signatures in sporadic E and vertical ion convergence rate, using FORMOSAT-3/COSMIC radio occultation observations and GAIA model, Earth, Planets and Space, doi.org/10.1186/s40623-022-01637-y, 74, 2022.08. |
| 7. |
YR. Kataoka, D. Shiota, H. Fujiwara, H. Jin, C. Tao, H. Shinagawa and Y. Miyoshi, Unexpected space weather causing the reentry of 38 Starlink satellites in February 2022, J. Space weather Space Climate, doi.org/10.1051/swsc/2022034, 12, 2022.12. |
| 8. |
Y. Yamazaki, C. Arras1, S. Andoh, Y. Miyoshi, H. Shinagawa, B. J.Harding, C. R. Englert, T. J. Immel, S. Sobhkhiz-Miandehi, Examining the Wind Shear Theory of Sporadic E with ICON/MIGHTI Winds and COSMIC-2 Radio Occultation Data, Geophysical Research Letters, doi.org/10.1029/2021GL096202, 49, 2022.01. |
| 9. |
Y. Yasui, K. Sato, and Y. Miyoshi, Roles of Rossby Waves, Rossby-Gravity Waves, and Gravity Waves Generated in the Middle Atmosphere for Interhemispheric Coupling, Journal of the Atmospheric Sciences, doi.org/10.1175/JAS-D-21-0045.1, 78, 3867-3888, 2021.12. |
| 10. |
Y. Yamazaki, V. Matthias, and Y. Miyoshi, Quasi-4-day wave:Atmospheric manifestation of the first symmetric Rossby normal mode of zonal wavenumber 2, J. Geophys. Res. Atmospheres, doi.org/10.1029/2021JD034855, 126, 2021.06. |
| 11. |
Y. Yamazaki, Y. Miyoshi, Ionospheric signatures of secondary waves from quasi-6-day wave and tide interactions, J. Geophys. Res. Space Physics, doi.org/10.1029/2020JA028360, 125, 2021.04. |
| 12. |
Mani Sivakandan,Y. Otsuka, Priyanka Ghosh, H. Shinagawa, A. Shinbori, and Y. Miyoshi, Comparison of seasonal and longitudinal variation of daytime MSTID activity using GPS observation and GAIA simulations, Earth Planets Space, doi.org/10.1186/s40623-021-01369-5, 73, 2021.02. |
| 13. |
Mani Sivakandan,Y. Otsuka, Priyanka Ghosh, H. Shinagawa, A. Shinbori, and Y. Miyoshi, Comparison of seasonal and longitudinal variation of daytime MSTID activity using GPS observation and GAIA simulations, Earth Planets Space, doi.org/10.1186/s40623-021-01369-5, 73, 2021.02. |
| 14. |
Shinagawa, H., C. Tao, H. Jin, Y. Miyoshi and H. Fujiwara, Numerical prediction of sporadic E layer occurrence using GAIA, Earth Planets Space, doi.org/10.1186/s40623-020-01307-x, 73, 2021.01. |
| 15. |
Tao, C., H. Jin, Y. Miyoshi, H. Shinagawa, H. Fujiwara, M. Nishioka, M. Ishii, Numerical Forecast of the Upper Atmosphere and Ionosphere using GAIA, Earth Planets Space, doi.org/10.1186/s40623-020-01307-x, 72, 2020.11. |
| 16. |
Y. Miyoshi, Y. Yamazaki, Excitation mechanism of ionospheric 6-day oscillation during the 2019 September sudden stratospheric warming event, J. Geophys. Res. Space Physics, doi.org/10.1029/2020JA028283, 125, 2020.09. |
| 17. |
Yamazaki, Y., Y. Miyoshi, C. Xiong, C. Stolle, G. Soares, and A. Yoshikawa, Whole atmosphere model simulations of ultra-fast Kelvin wave effects in the ionosphere and thermosphere, J. Geophys. Res. Space Physics, doi.org/10.1029/2020JA027939, 125, 2020.06. |
| 18. |
Y.Yamazaki, V. Matthias, Y.Miyoshi, C. Stolle, T. Siddiqui, G. Kervalishvili, J. Lastovicka, M. Kozubek, W. Ward, D. R. Themens, S. Kristoffersen, P. Alken, September 2019 Antarctic sudden stratospheric warming: Quasi-6-day wave burst and ionospheric effects, Geophysical Research Letters, doi.org/10.1029/2019GL086577, 47, 2020.01. |
| 19. |
Y. Miyoshi, E. Yigit, Impact of gravity wave drag on the thermospheric circulation:implementation of a nonlinear gravity wave parameterization in a whole-atmosphere model, Ann. Geophys., doi.org/10.5194/angeo-37-955-2019, 37, 955-969, 2019.10. |
| 20. |
Yang Yi Sun, Huixin Liu, Yasunobu Miyoshi, Loren C. Chang, Libo Liu, El 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, 71:35, 71:35, 2019.03, In this study, we evaluate the El Niño–Southern Oscillation (ENSO) signals in the two dominant temperature diurnal tides, diurnal westward wavenumber 1 (DW1) and diurnal eastward wavenumber 3 (DE3) on the quasi-biennial oscillation (QBO) scale (18–34 months) from 50 to 100 km altitudes. The tides are derived from the 21-year (January 1996–February 2017) Ground-to-Topside model of Atmosphere and Ionosphere for Aeronomy (GAIA) temperature simulations and 15-year (February 2002–February 2017) Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperature observations. The results show that ENSO warm phases shorten the period (~ 2 years) of the QBO in DW1 amplitude near the equator and DE3 amplitude at low latitudes of the Northern Hemisphere. In contrast, the QBO period lengthens (~ 2.5 years) during the ENSO neutral and cold phases. Correlation analysis shows the long-lasting effect of ENSO on the tidal QBO in the mesosphere and lower thermosphere.[Figure not available: see fulltext.].. |
| 21. |
Kazuhira Hoshi Jinro Ukita Meiji Honda Tetsu Nakamura Koji Yamazaki Yasunobu Miyoshi and Ralf Jaiser, Weak stratospheric polar vortex events modulated by the Arctic sea‐ice loss, Journal of Geophysical Research: Atmospheres, 10.1029/2018JD029222, 124, 858-869, 2019.01, We characterize the differences in the upward planetary‐scale wave propagation during observed weak polar vortex (WPV) events between heavy‐ and light‐sea‐ice years in the Barents‐Kara Sea based on a composite analysis for the period of 1979–2015. Upward wave propagation during WPV events in heavy‐ice years is dominated by the wavenumber 1 component. In contrast, WPV events occurring in light‐ice years are characterized by stronger wavenumber 2 propagation, which is caused by the tropospheric wavenumber 2 response to sea‐ice reduction in the Barents‐Kara Sea. The above observed features are supported by an Atmospheric General Circulation Model experiment. Thus, under present climate conditions, Arctic sea‐ice loss is a possible factor modulating the wave propagation during the WPV events. We also find that the WPV events in light‐ice years have stronger stratosphere‐troposphere coupling, followed by colder midlatitude surface conditions particularly over Eurasia.. |
| 22. |
Hiroyuki Shinagawa, Hidekatsu Jin, Yasunobu Miyoshi, Hitoshi Fujiwara, Tatsuhiro Yokoyama, Yuichi Otsuka, Daily and seasonal variations in the linear growth rate of the Rayleigh-Taylor instability in the ionosphere obtained with GAIA, Progress in Earth and Planetary Science, 10.1186/s40645-018-0175-8, 5, 1, 2018.12, The linear growth rates of the Rayleigh-Taylor (R-T) instability in the ionosphere from 2011 to 2013 were obtained with a whole atmosphere-ionosphere coupled model GAIA (ground-to-topside model of atmosphere and ionosphere for aeronomy). The effects of thermospheric dynamics driven by atmospheric waves propagating from below on the R-T growth rate are included in the model by incorporating meteorological reanalysis data in the region below 30 km altitude. The daily maximum R-T growth rates for these periods are compared with the observed occurrence days of the equatorial plasma bubble (EPB) determined by the Equatorial Atmosphere Radar (EAR) and Global Positioning System (GPS) in West Sumatra, Indonesia. We found that a high R-T growth rate tends to correspond to the actual EPB occurrence, suggesting the possibility of predicting EPB occurrences with numerical models. [Figure not available: see fulltext.].. |
| 23. |
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, In this study, we evaluate the El Niño–Southern Oscillation (ENSO) signals in the two dominant temperature diurnal tides, diurnal westward wavenumber 1 (DW1) and diurnal eastward wavenumber 3 (DE3) on the quasi-biennial oscillation (QBO) scale (18–34 months) from 50 to 100 km altitudes. The tides are derived from the 21-year (January 1996–February 2017) Ground-to-Topside model of Atmosphere and Ionosphere for Aeronomy (GAIA) temperature simulations and 15-year (February 2002–February 2017) Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperature observations. The results show that ENSO warm phases shorten the period (~ 2 years) of the QBO in DW1 amplitude near the equator and DE3 amplitude at low latitudes of the Northern Hemisphere. In contrast, the QBO period lengthens (~ 2.5 years) during the ENSO neutral and cold phases. Correlation analysis shows the long-lasting effect of ENSO on the tidal QBO in the mesosphere and lower thermosphere.[Figure not available: see fulltext.].. |
| 24. |
Mamoru Yamamoto, Yuichi Otsuka, Hidekatsu Jin, Yasunobu Miyoshi, Relationship between day-to-day variability of equatorial plasma bubble activity from GPS scintillation and atmospheric properties from Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy (GAIA) assimilation, Progress in Earth and Planetary Science, 10.1186/s40645-018-0184-7, 5, 1, 2018.12, The relationship between day-to-day variability of equatorial plasma bubbles (EPBs) and the neutral atmosphere is studied. This study is based on the previous study in which the GPS scintillation index and the tropospheric cloud-top temperature are used as proxies for EPB activity and atmospheric perturbations, respectively, and a correlation was found between their day-to-day variations. In this paper, we maintained the same GPS scintillation data but substituted the atmospheric data via an assimilation run of the Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy (GAIA). Cross-correlation between the EPB activity and the atmospheric temperature is similar to the results in Ogawa et al. (Earth Planets Space 61:397–410, 2009). The new findings from our study include (1) an enhanced correlation between the EPB activity and the neutral atmosphere is found in horizontally and vertically large areas, (2) the longitudinal disturbance of atmospheric temperature and wind velocity during the EPB-active days is enhanced, and (3) the enhancement of atmospheric disturbance during the EPB-active days shows a similarity to the characteristics of large-scale wave structures in the ionosphere. These results more clearly support couplings between EPBs and the neutral atmosphere. [Figure not available: see fulltext.].. |
| 25. |
Tao Yu, Yasunobu Miyoshi, Chunliang Xia, Xiaomin Zuo, Xiangxiang Yan, Na Yang, Yangyi Sun, Xinan Yue, and Tian Mao, Solar dependence of equatorial F region irregularities observed by COSMIC radio occultations, Journal of Geophysical Research: Space Physics, 10.1029/2018JA025936, 123, 9775-9787, 2018.11, With an improved method for retrieving the equatorial F region irregularities (EFIs) from radio occultation measurements, a huge amount of S4 index profiles from Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites is employed to study the solar cycle variation of global EFIs during the period of 2007 to 2017. This full solar cycle data show that impacts of the solar activity on the occurrence rates and heights of EFIs are notable and complex. The occurrence rates of EFIs at higher altitude (greater than 500 km) increase with increasing the solar activity. The mean heights ( ) and heights standard deviation (σh) of EFIs at higher altitudes do not show clearly the solar activity dependence. On the other hand, the occurrence rates of EFIs at entire altitudes (from 150 to 800 km) do not have clear relation with the solar activity. The and σh of EFIs at entire altitudes increase with increasing the solar activity. Moreover, the dependence of the occurrence rates of EFIs on the solar activity are the strongest in the equinoxes, weaker in winter and weakest in summer. The electric fields and corresponding seasonal variation can account for the EFIs occurrence and height variation versus solar activities, and the EFIs at low altitudes seem to be related to the seed associated with atmospheric gravity wave.. |
| 26. |
Kaoru Sato, Ryosuke Yasui, and Yasunobu Miyosh, The Momentum Budget in the Stratosphere, Mesosphere, and Lower Thermosphere. Part I: Contributions of Different Wave Types and In Situ Generation of Rossby Waves, Journal of the Atmospheric Sciences, 10.1175/JAS-D-17-0336.1, 75, 3613-3633, 2018.10, A momentum budget is examined in the stratosphere, mesosphere, and lower thermosphere using simulation data over ~11 years from a whole-atmosphere model in terms of the respective contributions of gravity waves (GWs), Rossby waves (RWs), and tides. The GW forcing is dominant in the mesosphere and lower thermosphere (MLT), as indicated in previous studies. However, RWs also cause strong westward forcing, described by Eliassen–Palm flux divergence (EPFD), in all seasons in the MLT and in the winter stratosphere. Despite the relatively coarse model resolution, resolved GWs with large amplitudes appear in the MLT. The EPFD associated with the resolved GWs is eastward (westward) in the summer (winter) hemisphere, similar to the parameterized GW forcing. A pair of positive and negative EPFDs are associated with the RWs and GWs in the MLT. These results suggest that the RWs and resolved GWs are generated in situ in the MLT. Previous studies suggested that a possible mechanism of RW generation in the MLT is the barotropic/baroclinic instability. This study revisits this possibility and examines causes of the instability from a potential vorticity (PV) viewpoint. The instability condition is characterized as the PV maximum at middle latitudes on an isentropic surface. Positive EPFD for RWs is distributed slightly poleward of the PV maximum. Because the EPFD equals the PV flux, this feature indicates that the RW radiation acts to reduce the PV maximum. The PV maximum is climatologically maintained in both the winter and summer mesospheres, which is caused by parameterized GW forcing.. |
| 27. |
Ryosuke Yasui, Kaoru Sato and Yasunobu Miyoshi, The Momentum Budget in the Stratosphere, Mesosphere, and Lower Thermosphere. Part II: The In Situ Generation of Gravity Waves, Journal of the Atmospheric Sciences, 10.1175/JAS-D-17-0337.1, 75, 3635-3651, 2018.10, The contributions of gravity waves to the momentum budget in the mesosphere and lower thermosphere (MLT) is examined using simulation data from the Ground-to-Topside Model of Atmosphere and Ionosphere for Aeronomy (GAIA) whole-atmosphere model. Regardless of the relatively coarse model resolution, gravity waves appear in the MLT region. The resolved gravity waves largely contribute to the MLT momentum budget. A pair of positive and negative Eliassen–Palm flux divergences of the resolved gravity waves are observed in the summer MLT region, suggesting that the resolved gravity waves are likely in situ generated in the MLT region. In the summer MLT region, the mean zonal winds have a strong vertical shear that is likely formed by parameterized gravity wave forcing. The Richardson number sometimes becomes less than a quarter in the strong-shear region, suggesting that the resolved gravity waves are generated by shear instability. In addition, shear instability occurs in the low (middle) latitudes of the summer (winter) MLT region and is associated with diurnal (semidiurnal) migrating tides. Resolved gravity waves are also radiated from these regions. In Part I of this paper, it was shown that Rossby waves in the MLT region are also radiated by the barotropic and/or baroclinic instability formed by parameterized gravity wave forcing. These results strongly suggest that the forcing by gravity waves originating from the lower atmosphere causes the barotropic/baroclinic and shear instabilities in the mesosphere that, respectively, generate Rossby and gravity waves and suggest that the in situ generation and dissipation of these waves play important roles in the momentum budget of the MLT region.. |
| 28. |
Yasunobu Miyoshi, Hidekatsu Jin, Hitoshi Fujiwara, Hiroyuki Shinagawa, Numerical Study of Traveling Ionospheric Disturbances Generated by an Upward Propagating Gravity Wave, Journal of Geophysical Research, 10.1002/2017JA025110, 123, 3, 2141-2155, 2018.03, Using a global atmosphere-ionosphere coupled model, the characteristics and excitation source of traveling ionospheric disturbances (TIDs) during geomagnetically quiet periods are studied. This is the first paper concerning the simulation of TIDs generated by upward propagating gravity waves (GWs) that are spontaneously generated in the model. The dominant horizontal wavelengths of the simulated TIDs range from 700 to 1,500 km. The dominant periods and horizontal phase velocities of TIDs are 45–90 min and 250–300 m s−1, respectively. These features are the same as those of GWs in the 250–300 km height region. The phase of the electron density variations due to TIDs descends with increasing time, which is characteristic of the upward propagation of GWs. These electron density variations that are caused due to TIDs are explained by the transport processes of a neutral wind along a geomagnetic field line. These results indicate that the electron density variations respond locally to the passage of neutral wind fluctuations associated with upward propagating GWs. The GWs that excite TIDs are secondary GWs, which are generated in the mesosphere and lower thermosphere via the dissipation/breaking of tropospheric GWs. The magnitudes of TIDs at middle latitudes are larger in winter than in summer. The mechanisms of seasonal and day-to-day variations in TIDs that are caused due to GWs are discussed in this study.. |
| 29. |
Shigeru Fujita, Yuka Murata, Ikuko Fujii, Yasunobu Miyoshi, Hiroyuki Shinagawa, Hidekatsu Jin, Hitoshi Fujiwara, Evaluation of the Sq Magnetic Field Variation Calculated by GAIA, Space Weather, 10.1002/2017SW001745, 2018.01, Magnetic variations calculated by the Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy (GAIA) are compared with those observed at global magnetic observatory network in geomagnetic calm days in order to evaluate accuracy of the ionospheric current system calculated by GAIA. The calculated Y component magnetic variations can reproduce more than 50% of the observed variations at more than half observatories treated. In particular, GAIA can reproduce more than 75% of the observed Y component variations in the equinox, whereas there is tendency of low correlation of the waveform between the calculated and observed variations in the winter season. Next, GAIA reproduces so well of the X component variations at the low-latitude observatories. Low correlation between the calculated and observed X component variations at middle-latitude observatories seems to be caused by inaccurate determination of the position of the ionospheric Sq current vortex. Last, although the calculated Z component variations do not so well reproduce the observed ones compared with other component, GAIA can reproduce more than 50% of the observed Z component variation at about half observatories in general. Calculated amplitude of the horizontal magnetic variations (X and Y components) exhibit smaller than the observed one whereas that of the vertical variation (Z component) is larger than the observed one. This tendency is roughly explained by the induction effect of the Earth that is not considered in GAIA. Thus, GAIA considerably well reproduces the pure ionospheric current system that is not affected by the solid Earth.. |
| 30. |
Fabio Egito, Hisao Takahashi, Yasunobu Miyoshi, Effects of the planetary waves on the MLT airglow, Annales Geophysicae, 10.5194/angeo-35-1023-2017, 35, 5, 1023-1032, 2017.08, The planetary-wave-induced airglow variability in the mesosphere and lower thermosphere (MLT) is investigated using simulations with the general circulation model (GCM) of Kyushu University. The model capabilities enable us to simulate the MLT OI557.7ĝ€nm, O2b(0-1), and OH(6-2) emissions. The simulations were performed for the lower-boundary meteorological conditions of 2005. The spectral analysis reveals that at middle latitudes, oscillations of the emission rates with the period of 2-20 days appear throughout the year. The 2-day oscillations are prominent in the summer and the 5-, 10-, and 16-day oscillations dominate from the autumn to spring equinoxes. The maximal amplitude of the variations induced by the planetary waves was 34ĝ€% in OI557.7ĝ€nm, 17ĝ€% in O2b(0-1), and 8ĝ€% in OH(6-2). The results were compared to those observed in the middle latitudes. The GCM simulations also enabled us to investigate vertical transport processes and their effects on the emission layers. The vertical transport of atomic oxygen exhibits similar periodic variations to those observed in the emission layers induced by the planetary waves. The results also show that the vertical advection of atomic oxygen due to the wave motion is an important factor in the signatures of the planetary waves in the emission rates.. |
| 31. |
Huixin Liu, Yang Yi Sun, Yasunobu Miyoshi, Hidekatsu Jin, ENSO effects on MLT diurnal tides
A 21 year reanalysis data-driven GAIA model simulation, Journal of Geophysical Research, 10.1002/2017JA024011, 122, 5, 5539-5549, 2017.05, Tidal responses to El Niño–Southern Oscillation (ENSO) in the mesosphere and lower thermosphere (MLT) are investigated for the first time using reanalysis data-driven simulations covering 21 years. The simulation is carried out with the Ground-to-topside Atmosphere-Ionosphere model for Aeronomy (GAIA) during 1996–2016, which covers nine ENSO events. ENSO impacts on diurnal tides at 100 km altitude are analyzed and cross-compared among temperature (T), zonal wind (U), and meridional wind (V), which reveals the following salient features: (1) Tidal response can differ significantly among T, U, and V in terms of magnitude and latitudinal structure, making detection of ENSO effects sensitive to the parameter used and the location of a ground station; (2) the nonmigrating DE3 tide in T and U shows a prominent hemisphere asymmetric response to La Niña, with an increase between 0° and 30°N and a decrease between 30° and 0°S. In contrast, DE3 in V exhibits no significant response; (3) the migrating DW1 enhances during El Niño in equatorial regions for T and U but in off-equatorial regions for V. As the first ENSO study based on reanalysis-driven simulations, GAIA's full set of tidal responses in T, U, and V provides us with a necessary global context to better understand and cross-compare observations during ENSO events. Comparisons with observations during the 1997–98 El Niño and 2010–11 La Niña reveal good agreement in both magnitude and timing. Comparisons with “free-run” WACCM simulations (T) show consistent results in nonmigrating tides DE2 and DE3 but differences in the migrating DW1 tide.. |
| 32. |
Yasunobu Miyoshi, Dora Pancheva, Plamen Mukhtarov, Hidekatsu Jin, Hitoshi Fujiwara, Hiroyuki Shinagawa, Excitation mechanism of non-migrating tides, Journal of Atmospheric and Solar-Terrestrial Physics, 10.1016/j.jastp.2017.02.012, 156, 24-36, 2017.04, Using an atmosphere-ionosphere coupled model, the excitation source and temporal (seasonal and interannual) variations in non-migrating tides are investigated in this study. We first focus our attention on temporal variations in eastward moving diurnal tide with zonal wavenumber 3 (DE3), which is the largest of all the non-migrating tides in the mesosphere and lower thermosphere (MLT). Our simulation results indicate that upward propagation of the DE3 excited in the troposphere is sensitive to the zonal mean zonal wind in the stratosphere and mesosphere. The DE3 amplitude is enhanced in the region where the vertical shear of the zonal mean zonal wind is positive (westerly shear). Quasi-2-year variation in the DE3 amplitude in the MLT region is generated by quasi-2-year variation in the zonal mean zonal wind between 40 and 70 km, which is modulated by the stratospheric QBO. The excitation mechanisms of SW3 (westward moving semidiurnal tide with zonal wavenumber 3) and SW1 (westward moving semidiurnal tide with zonal wavenumber 1) are also investigated. During equinoxes, the SW3 and SW1 are excited by tropospheric heating (latent heat release and solar radiative heating) associated with cumulus convection in the tropics, and propagate upward into the MLT region. On the other hand, during solstices, SW3 and SW1 are generated in the winter stratosphere and mesosphere through the nonlinear interaction between the stationary planetary wave and migrating semidiurnal tide, and propagate upward to the lower thermosphere. The excitation sources of other non-migrating tides are also discussed.. |
| 33. |
H. Shinagawa, Yasunobu Miyoshi, H. Jin, H. Fujiwara, Global distribution of neutral wind shear associated with sporadic E layers derived from GAIA, Journal of Geophysical Research, 10.1002/2016JA023778, 122, 4, 4450-4465, 2017.04, There have been a number of papers reporting that the statistical occurrence rate of the sporadic E (Es) layer depends not only on the local time and season but also on the geographical location, implying that geographical and seasonal dependence in vertical neutral wind shear is one of the factors responsible for the geographical and seasonal dependence in Es layer occurrences rate. To study the role of neutral wind shear in the global distribution of the Es layer occurrence rate, we employ a self-consistent atmosphere-ionosphere coupled model called GAIA (Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy), which incorporates meteorological reanalysis data in the lower atmosphere. The average distribution of neutral wind shear in the lower thermosphere is derived for the June–August and December–February periods, and the global distribution of vertical ion convergence is obtained to estimate the Es layer occurrence rate. It is found that the local and seasonal dependence of neutral wind shear is an important factor in determining the dependence of the Es layer occurrence rate on geographical distribution and seasonal variation. However, there are uncertainties in the simulated vertical neutral wind shears, which have larger scales than the observed wind shear scales. Furthermore, other processes such as localization of magnetic field distribution, background metallic ion distribution, ionospheric electric fields, and chemical processes of metallic ions are also likely to make an important contribution to geographical distribution and seasonal variation of the Es occurrence rate.. |
| 34. |
Yosuke Yamazaki, Huixin Liu, Yang Yi Sun, Yasunobu Miyoshi, Michael J. Kosch, Martin G. Mlynczak, Quasi-biennial oscillation of the ionospheric wind dynamo, Journal of Geophysical Research, 10.1002/2016JA023684, 122, 3, 3553-3569, 2017.03, The interannual variation of the ionospheric solar quiet (Sq) current system is examined. A dense magnetometer network over Japan enables the accurate determination of the central position of the northern Sq current loop or the Sq current focus, during 1999–2015. It is found that the Sq focus latitude undergoes an interannual variation of ±2° with a period of approximately 28 months, similar to the quasi-biennial oscillation (QBO) in the tropical lower stratosphere. The QBO-like variation of Sq is particularly evident during 2005–2013. No corresponding interannual variability is found in solar extreme ultraviolet radiation. Comparisons with tidal winds, derived from a whole-atmosphere model, reveal that the QBO-like variation of the Sq current focus is highly correlated with the amplitude variations of migrating and nonmigrating diurnal tides in the lower thermosphere. The results suggest that the stratospheric QBO can influence the ionospheric wind dynamo through the QBO modulation of tides.. |
| 35. |
Tetsu Nakamura, Koji Yamazaki, Katsushi Iwamoto, Meiji Honda, Yasunobu Miyoshi, Yasunobu Ogawa, Yoshihiro Tomikawa, Jinro Ukita, The stratospheric pathway for Arctic impacts on midlatitude climate, Geophysical Research Letters, 10.1002/2016GL068330, 43, 7, 3494-3501, 2016.04, Recent evidence from both observations and model simulations suggests that an Arctic sea ice reduction tends to cause a negative Arctic Oscillation (AO) phase with severe winter weather in the Northern Hemisphere, which is often preceded by weakening of the stratospheric polar vortex. Although this evidence hints at a stratospheric involvement in the Arctic-midlatitude climate linkage, the exact role of the stratosphere remains elusive. Here we show that tropospheric AO response to the Arctic sea ice reduction largely disappears when suppressing the stratospheric wave mean flow interactions in numerical experiments. The results confirm a crucial role of the stratosphere in the sea ice impacts on the midlatitudes by coupling between the stratospheric polar vortex and planetary-scale waves. Those results and consistency with observation-based evidence suggest that a recent Arctic sea ice loss is linked to midlatitudes extreme weather events associated with the negative AO phase.. |
| 36. |
Yasunobu Miyoshi, Hitoshi Fujiwara, Hidekatsu Jin, Hiroyuki Shinagawa, Impacts of sudden stratospheric warming on general circulation of the thermosphere, Journal of Geophysical Research, doi:10.1002/2015JA021894, 120, 2015.12. |
| 37. |
T. Nakamura, K.Yamazaki, K. Iwamoto, M. Honda, Yasunobu Miyoshi, Y. Ogawa, J. Ukita, A negative phase shift of the winter AO/NAO due to the recent Arctic sea-ice reduction in late autumn, Journal of Geophysical Research, doi:10.1002/2014JD022848, 2015, 120, 3209-3227, 2015.04. |
| 38. |
L. C. Chang, Huixin Liu, Yasunobu Miyoshi, C.-H. Chen, F-Y. Chang, C.-H. Lin, J.-Y. Liu, Y.-Y. Sun, Structure and origins of the Weddell Sea Anomaly from tidal and Planetary wave signitures in FORMOSAT-3/COSMIC observations and GAIAGCM simulations, Journal of Geophysical Research, doi:10.1002/2014JA020752, 120, 2015.01. |
| 39. |
Huixin Liu, Yasunobu Miyoshi, Saburo Miyahara, Hidekatsu Jin, Hitoshi Fujiwara, Hiroyuki Shinagawa, Thermal and dynamical changes of the zonal mean state of the thermosphere during the 2009 SSW:GAIA simulations, Journal of Geophysical Research, doi:10.1002/2014JA020222, 119, 2014.07. |
| 40. |
H. Fujiwara, S. Nozawa, Y. Ogawa, R. Kataoka, Yasunobu Miyoshi, H. Jin, H. Shinagawa, Extreme ion heating in the dayside ionosphere in response to the arrival of a coronal mass ejection on 12 March 2012, Annales Geophysicae, doi:10.5194/angeo-32-831-2014, 32, 831-839, 2014.07. |
| 41. |
Yasunobu Miyoshi, Hitoshi Fujiwara, Hidekatsu Jin, Hiroyuki Shinagawa, A global view of gravity waves in the thermosphere simulated by a general circulation model, J. Geophys. Res., doi:10.1002/2014JA019848, 119, 2014.06. |
| 42. |
N. M. Pedatella, T. Fuller-Rowell, H. Wang, H. Jin, Yasunobu Miyoshi, H. Fujiwara, H. Shinagawa, H.-L. Liu, F. Sassi, H. Schmidt, V.Matthias, L. Goncharenko, The neutral dynamics during the 2009 sudden stratosphere warming simulated by different whole atmosphere models, Journal of Geophysical Research, doi:10.1002/2013JA019421., 2014.01. |
| 43. |
Huixin Liu, Hidekatsu Jin, Yasunobu Miyoshi, Hitoshi Fujiwara, Hiroyuki Shinagawa, Upper atmosphere response to stratosphere sudden warming: Local time height dependence simulated by GAIA model, Geophysical Research Letters, 10.1002/grl.50146, 2013, 40, 2013.02. |
| 44. |
Hidekatsu Jin, Yasunobu Miyoshi, Dora Pancheva, P. Mukhtarov, Hitoshi Fujiwara, Hiroyuki Shinagawa, Response of migrating tides to the stratospheric sudden warming in 2009 and their effects on the ionosphere studied by a whole atmosphere-ionosphere model GAIA with COSMIC and TIMED/SABER observations, J. Geophys. Res., doi:10.1029/2012JA017650, 117, A10323, 2012.10. |
| 45. |
Dora Pancheva, Yasunobu Miyoshi, P. Mukhtarov, Hidekatsu Jin, Hitoshi Fujiwara, Hiroyuki Shinagawa, Global response of the ionosphere to atmospheric tides forced from below: Comparison between COSMIC measurements and simulations by Atmosphere-Ionosphere Coupled Model GAIA, J. Geophys. Res., doi:10.1029/2011JA017452, 117, A07319, 2012.07. |
| 46. |
Dora Pancheva, Yasunobu Miyoshi, P. Mukhtarov, Hidekatsu Jin, Hitoshi Fujiwara, Hiroyuki Shinagawa, Global response of the ionosphere to atmospheric tides forced from below: Comparison between COSMIC measurements and simulations by Atmosphere-Ionosphere Coupled Model GAIA, J. Geophys. Res., doi:10.1029/2011JA017452, 117, A07319, 2012.07. |
| 47. |
Hitoshi Fujiwara, Satonori Nozawa, Sawako Maeda, Yasunobu Ogawa, Yasunobu Miyoshi, Hidekatsu Jin, Hiroyuki Shinagawa, Kaori Terada, Polar cap thermosphere and ionosphere during the solar minimum period: EISCAT Svalbard radar observations and GCM simulations, Earth, Planet and Space, 64, 6, 459-465, 2012.06. |
| 48. |
Miyoshi, Y., H. Jin, H. Fujiwara, H. Shinagawa and H. Liu, Wave-4 structure of the neutral density in the thermosphere and its relation to atmospheric tide, J. Sol.-Terr. Phys., doi:10.1016/j.jastp.2011.12.002, 2012.05. |
| 49. |
Miyoshi, Y., H. Fujiwara, H. Jin, H. Shinagawa and H. Liu, Numerical simulation of the equatorial wind jet in the thermosphere, Journal of Geophysical Research, doi:10.1029/2011JA017373, 117, A03, A03309, 2012.03. |
| 50. |
Miyoshi, Y., J. M. Forbes, and Y. Moudden, A new perspective on gravity waves in the Martian atmosphere: Sources and feature, Journal of Geophysical Research, doi:10.1029/2011JE003800, 116, E09, E9009, 2011.09. |
| 51. |
Miyoshi, Y., H. Fujiwara, H. Jin, H. Shinagawa, H. Liu, and K. Terada, Model Study on the Formation of the Equatorial Mass Density Anomaly in the Thermosphere, Journal of Geophysical Research, doi:10.1029/2010JA016315, 116, A05322, A05322, 2011.05. |
| 52. |
Venkateswara Rao, N., T. Tsuda, S. Gurubaran, Y. Miyoshi, and H. Fujiwara, On the occurrence and variability of the terdiurnal tide in the equatorial Mesosphere and Lower Thermosphere and its comparison with the Kyushu-GCM, Journal of Geophysical Research, doi:10.1029/ 2010JD014529, 116, D02, D02117, 2011.01. |
| 53. |
Jin, H., Y. Miyoshi, H. Fujiwara, H. Shinagawa, K. Terada, N. Terada, M. Ishii, Y. Otsuka, and A. Saito, Vertical connection from the tropospheric activities to the ionospheric longitudinal structure simulated by a new Earth's whole atmosphere-ionosphere coupled model, Journal of Geophysical Research, 10.1029/2010JA015925, 116, A01, A01316, 2011.01. |
| 54. |
Hitoshi Fujiwara and Yasunobu Miyoshi, Morphological features and variations of temperature in the upper thermosphere simulated by a whole atmosphere GCM, Annales Geophysicae, 25, 427-437, 2010.10. |
| 55. |
Fujiwara, H., Y. Miyoshi , H. Jin, H. Shinagawa, Y. Otsuka, A. Saito, and M. Ishii, Thermospheric temperature and density variations, Proceedings IAU Symposium No. 264, Solar and Stellar Variability Impact on Earth and Planets, International Astronomical Union 2010, doi:10.1017/S1743921309992857, 310-319, 2010.03. |
| 56. |
Y. Miyoshi, and H. Fujiwara, J. M. Forbes and S. Bruinsma, Solar terminator wave and its relation to the atmospheric tide, Journal of Geophysical Research, doi:10.1029/2009JA014110, 114, A07303, A07303, 2009.07. |
| 57. |
Hidekatsu Jin, Yasunobu Miyoshi, Hitoshi Fujiwara and Hiroyuki Shinagawa, Electrodynamics of the formation of ionospheric wave number 4 longitudinal structure, Journal of Geophysical Research, Vol. 113, A09307, doi:10.1029/2008JA013301, 2008.09. |
| 58. |
Forbes, J. M., S. Bruinsma, Y. Miyoshi, and H. Fujiwara, A solar terminator wave in thermosphere neutral densities measured by the CHAMP satellite, Geophysical Research Letters, Vol. 35, L14802, doi:10.1029/2008GL034075, 2008.07. |
| 59. |
Yasunobu Miyoshi and Hitoshi Fujiwara, Gravity waves in the thermosphere simulated by a general circulation model, Journal of Geophysical Research, Vol. 113, D01101, doi:10.1029/2007JD008874, 2008.01. |
| 60. |
Hitoshi Fujiwara and Yasunobu Miyoshi, Morphological features and variations of temperature in the upper thermosphere simulated by a whole atmosphere GCM, Annales Geophysicae, 25, 427-437, 2006.10. |
| 61. |
Hitoshi Fujiwara and Yasunobu Miyoshi, Characteristics of the large-scale traveling atmospheric disturbances during geomagnetically quite and disturbed periods simulated by a whole atmosphere general circulation mode, Geophysical Research Letters, Vol.33, L20108, doi:10.1029/2006GL027103., 2006.10. |
| 62. |
Yasunobu Miyoshi, Hitoshi Fujiwara, Excitation mechanism of intraseasonal oscillation in the mesosphere and lower thermosphere, Journal of Geopgysical Research, Vol. 111, D14108, doi:10.1029/2005JD006993, 2006.07. |
| 63. |
Yasunobu Miyoshi, Temporal variation of nonmigrating diurnal tide and its relation with the moist convective activity, Geophysical Research Letters, Vol. 33, L11815, doi:10.1029/2006GL026072, 2006.06. |
| 64. |
Yasunobu Miyoshi, Hitoshi Fujiwara, Day-to-day variations of migrating semidiurnal tide in the mesosphere and thermosphere, Memorirs of national Institute of Polar Research, Vol. 59, 199-207P., 2006.03. |
| 65. |
Yasunobu Miyoshi and Hitoshi Fujiwara, Day-to-day variations of migrating semidiurnal tide simulated by a general circulation model, Advances in Polar Upper Atmosphere Research, Vol18, Page 87-95., 2004.08. |
| 66. |
Yasunobu Miyoshi, Effects of the stratospheric sudden warmining on the temperature in the MLT region, Advances in Polar Upper Atmosphere Research, Vol. 17, Page 1-12., 2003.12. |
| 67. |
Yasunobu Miyoshi and Toshihiko Hirooka, Quasi-biennial variation of the 5-day wave in the stratosphere, Journal of Geophysical Research, 10.1029/2002JD003145, 108, D19, Vol. 108, 4620, doi:10.1029/2002JD003145., 2003.10. |
| 68. |
Yasunobu Miyoshi and Hitoshi Fujiwara, Day-to-day variations of migrating diurnal tide simulated by a GCM from the ground surface to the exobase, Geophysical Research Letters, 10.1029/2003GL017695, 30, 15, Vol. 30, 1789, doi:10.1029/2003GL017695., 2003.08. |
| 69. |
Jeffery M. Forbes, Maura E. Hagan, Saburo Miyahara, Yasunobu Miyoshi and Xiaoli Zhang, Diurnal nonmigrating tides in the tropical lower thermosphere, Earth, Planets and Space, 55, 7, 419-426, Vol. 55, Page 419-426., 2003.07. |
| 70. |
K.M. Cierpik, J.M. Forbes, S. Miyahara, Y. Miyoshi, A. Fahrutdinova, C. Jacobi, A. Manson, C. Meek, N.J. Mitchell and Y. Portnyagin, Longitude variability of the solar semidiurnal tide in the lower thermosphere through assimilation of ground- and space- based wind measurements, Journal of Geophysical Research, 10.1029/2002JA009349, 108, A5, Vol108(A5), 1202., 2003.05. |
| 71. |
Saburo Miyahara, Daisuke Yamamoto, and Yasunobu Miyoshi, On the geostrophic balance of mean zonal winds in the mesosphere and lower thermosphere, Journal of Meteorological Society of Japan, 78, 5, 683-688, Vol. 78, Page 683-688., 2000.10. |
| 72. |
Kohji Yamashita, Saburo Miyahara, Yasunobu Miyoshi, Keiko Kawano and Jyunko Ninomiya, Seasonal variation of non-migrating semidiurnal tide in the polar MLT region in a general circulation model, Journal of Atmosphere and Solar-Terrestrial Physics, 10.1016/S1364-6826(02)00059-7, 64, 8-11, 1083-1094, Vol. 64, Page 1083-1094., 2000.05. |
| 73. |
Saburo Miyahara, Yasunobu Miyoshi and Kohji Yamashita, Variations of migrating and non-migrating tides simulated by the middle atmosphere circulation model at Kyushu University, Advances in Space Research, 10.1016/S0273-1177(99)00879-0, 24, 11, 1549-1558, Vol.24, Page 1549-1558., 1999.11. |
| 74. |
Yasunobu Miyoshi, Numerical simulation of the 5-day and 16-day waves in the mesopause region, Earth, Planets and Space, 51, 7-8, 763-772, Vol. 51, Page 763-772., 1999.07. |
| 75. |
Shingo Watanabe, Saburo Miyahara and Yasunobu Miyoshi, Lagrangian transport experiments in the MLT region, Earth, Planets and Space, 51, 7-8, 745-750, Vol.51, Page 745-750., 1999.07. |
| 76. |
Yasunobu Miyoshi and Toshihiko Hirooka, A numerical experiment of excitation of the 5-day wave by a GCM, Journal of Atmospheric Sciences, 10.1175/1520-0469(1999)0562.0.CO;2, 56, 11, 1698-1707, Vol. 56, Page 1698-1707., 1999.06. |
| 77. |
Title:Lagrangian transport and chemistry in the mesopause region - the relationship between the lagrangian meridional circulation and distribution of O(1S)
Name:Shingo Watanabe, Saburo Miyahara, Yasunobu Miyoshi and Kenshi Goya
Proceedings of 8th sympojium of atmopsheric chemistry, Page 141-144, published by Solar Terrestrial Enviromental Laboratory, Nagoya University. |
