Keywords: middle atmosphere, stratospheric sudden warmings (SSWs), gravity waves

Performing hindcast simulations of boreal winters (December-January-February) with the gravity wave-permitting high-top (~150 km) general circulation model,the Japanese Atmospheric General circulation model for Upper Atmosphere Research (JAGUAR), I am working on research on dynamical phenomena in the whole middle atmosphere. The roles of gravity waves and their interplay with planetary waves in such dynamical phenomena are the main focuses of my research.

In my previous research, we performed an observational study about gravity waves (GWs) in the mid-latitude summer stratosphere by hodograph analysis method (Sato, 1994) using the 23 years high-resolution radiosonde observation data from nine stations in the subtropics and mid-latitudes of Japan. (Okui and Sato (2020) for more details).