14:00 〜 14:15
[AAS10-02] Response of Large-Scale Gravity Waves to Stratospheric Sudden Warming in the thermosphere
using ICON/MIGHTI and SD-WACCM-X.
★Invited Papers
キーワード：Gravity Wave, Stratospheric Sudden Warming
Understanding atmospheric coupling from the troposphere/stratosphere to the upper atmosphere is important for improving climate simulations and space weather forecast. Gravity waves are one of the key elements for driving the atmospheric coupling from the troposphere/stratosphere to the mesosphere and thermosphere. This presentation will focus on the 2021 stratospheric sudden warming (SSW) event to study coupling processes. SSWs are one of the largest anomalies in the stratosphere. Although SSW events occur in the winter polar stratosphere, impacts of SSWs have been observed globally from the troposphere to the thermosphere. Atmospheric waves (planetary waves, tides, and gravity waves) are believed to be main drivers for coupling process during SSWs.
In this talk, validations of large-scale gravity waves in SD-WACCM-X simulations against MIGHTI (Michelson Interferometer for Global High-resolution Thermospheric) instruments on the Ionospheric Connection Explorer (ICON) will be presented for both seasonal variations and day-to-day variations. After validations of gravity waves in SD-WACCM-X, responses of large-scale gravity wave to the 2021 SSW will be presented using MIGHTI instrument and SD-WACCMX nudged by GEOS-5. During the 2021 SSW in January, both MIGHTI satellite observations and SD-WACCM simulation show increases of large-scale gravity wave amplitudes in the low-mid latitude thermosphere. Our analysis indicates that increase of gravity waves in the thermosphere are related to both changes in in-situ sources due to distorted polar vortex and changes in propagation due to background wind change.
In this talk, validations of large-scale gravity waves in SD-WACCM-X simulations against MIGHTI (Michelson Interferometer for Global High-resolution Thermospheric) instruments on the Ionospheric Connection Explorer (ICON) will be presented for both seasonal variations and day-to-day variations. After validations of gravity waves in SD-WACCM-X, responses of large-scale gravity wave to the 2021 SSW will be presented using MIGHTI instrument and SD-WACCMX nudged by GEOS-5. During the 2021 SSW in January, both MIGHTI satellite observations and SD-WACCM simulation show increases of large-scale gravity wave amplitudes in the low-mid latitude thermosphere. Our analysis indicates that increase of gravity waves in the thermosphere are related to both changes in in-situ sources due to distorted polar vortex and changes in propagation due to background wind change.