[A-CG29] Extratropical oceans and atmosphere

[ACG29-P02] AGCM experiments for winters of 2017/18 and 2019/20

*Kazuaki Nishii¹, Bunmei Taguchi², Hisashi Nakamura³ (1.Graduate School of Bioresources, Mie University, 2. Faculty of Sustainable Design, University of Toyama , 3.RCAST, The University of Tokyo)

Keywords:midlatitude ocean, atmospheric general circulation model

We conducted AGCM experiments for 2017/18 winter when Japan suffered from a cold surge, as well as for 2019/20 winter when Japan experienced unusually warminess. Our AGCM cannot reproduce the 2017/18 cold winter in Japan. This may be because convective activity over the eastern Indian Ocean is suppressed too much in response to cool SST anomalies there. The extratropical SST anomalies also contributed to the warminess. While in the 2019/20 winter, our AGCM can successfully simulate the warminess around Japan. This is associated with well simulation of convective activity over the Indian Ocean, and the maritime continent. The extratropical SST anomalies also contributed to the formation of the anticyclonic anomalies and warming over Japan.