Japan Geoscience Union Meeting 2021

Presentation information

[J] Oral

A (Atmospheric and Hydrospheric Sciences ) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS07] Weather, Climate, and Environmental Science Studies using High-Performance Computing

Fri. Jun 4, 2021 10:45 AM - 12:15 PM Ch.07 (Zoom Room 07)

convener:Hisashi Yashiro(National Institute for Environmental Studies), Takuya Kawabata(Meteorological Research Institute), Tomoki Miyakawa(Atmosphere and Ocean Research Institute, The University of Tokyo), Koji Terasaki(RIKEN Center for Computational Science), Chairperson:Takuya Kawabata(Meteorological Research Institute)

11:45 AM - 12:00 PM

[AAS07-11] Global large ensemble simulations with a cloud-resolving atmosphere and eddy-resolving ocean model

*Ryusuke Masunaga1, Tomoki Miyakawa1 (1.Atmosphere and Ocean Research Institute, The University of Tokyo)

Global large ensemble simulations over several months with a cloud-resolving (14 km resolution or finer) atmosphere, eddy-resolving (0.1 degrees resolution) ocean model, and their coupled system have become feasible thanks to the development of high-power supercomputer “Fugaku”. This is an unprecedented opportunity to explore the roles of the interaction between mesoscale atmospheric convections and ocean eddies on the global climate system.
Atmospheric convection over the tropical region can yield anomalous atmospheric circulations over the globe. Meanwhile, recent studies have shown that mesoscale ocean perturbations can trigger deep atmospheric convections, and thus exert remote and basin-scale impacts on the atmospheric circulation. Thus, it is of great importance to explore the role of the mesoscale air-sea interaction by using a global atmosphere-ocean coupled system.
We are assessing performance and utility of the high-resolution coupled system by comparing it with a lower-resolution (with a 0.25 degrees resolution ocean component) system. The representation of the mesoscale ocean features over the midlatitude regions are substantially improved in the high-resolution coupled system. Furthermore, the climatic drift in sea-surface temperature tends to be suppressed over the subtropical region, in particular the North Atlantic. These improvement in the surface ocean state can lead to better representation in the atmospheric state and better sub-seasonal to seasonal forecasts.