Wave coupling processes between the lower and upper atmospheres simulated by a whole atmosphere model (GAIA)
Abstract
Wave coupling processes between the lower and upper atmospheres are examined using a whole atmosphere model. We have developed a whole atmosphere model (GAIA), which includes the region from the ground surface to the upper thermosphere/ ionosphere. Furthermore, GAIA includes interaction processes between the ionosphere and neutral atmosphere. In this study, we focus on behaviors of gravity waves (GWs) in a whole atmosphere. We study excitation of GWs in the lower atmosphere, their upward propagation to the mesosphere and thermosphere, and their impacts on the thermosphere/ionosphere system. Our results indicate that the GW activity in the thermosphere is affected by temporal variations of the eastward jet in the troposphere and stratosphere. For example, the GW activity in the thermosphere is attenuated during a stratospheric sudden warming event. This attenuation of the GW activity is explained by the fact that reversal or weakening of strato-mesospheric jet affects vertical propagation condition of GWs from the lower atmosphere to upper atmosphere. Furthermore, we investigate impacts of thermospheric GWs on the ionospheric variability.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMSA42A..01M
- Keywords:
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- 3334 Middle atmosphere dynamics;
- ATMOSPHERIC PROCESSESDE: 3369 Thermospheric dynamics;
- ATMOSPHERIC PROCESSESDE: 3384 Acoustic-gravity waves;
- ATMOSPHERIC PROCESSESDE: 3389 Tides and planetary waves;
- ATMOSPHERIC PROCESSES