4:30 PM - 4:45 PM
[AAS08-10] Global simulations with a cloud-resolving atmosphere and eddy-resolving ocean coupled model in winter and summer
It is well known that atmospheric convection plays an important role in the Earth's climate and weather system. Likewise, recent studies have shown that mesoscale ocean features such as ocean eddies can exert significant impacts on the atmospheric circulation. To resolve these fine-scale features in a numerical model, the horizontal resolution is required to be O(10km) or even finer. Thanks to the development of Supercomputer “Fugaku”, it has been made achievable to conduct global ensemble simulations over several weeks with a high-resolution coupled model. In the present study, we conducted 10 ensemble simulations with the global coupled model named NICOCO over 40 days in midwinter 2020 and midsummer 2016. NICOCO consists of a cloud-resolving (3.5 km resolution) atmospheric model NICAM and eddy-resolving (0.1 degrees resolution) ocean model COCO.
We have confirmed that the representation in the surface ocean is substantially improved in the high-resolution coupled model compared with a lower-resolution model in which the ocean resolution is 0.25 degrees. In winter, surface wind convergence and precipitation are intensified near the sea-surface temperature (SST) front along the Kuroshio and ocean eddies. In summer, rapid cooling of SST is clearly identified after the passage of typhoons. The signature of the typhoons lasts 10 days and more. The Kuroshio is also cooled due to the typhoons, but it recovers rapidly to the original high SST. This is an unprecedented opportunity to investigate the role of mesoscale air-sea interaction on the global climate system.
Acknowledgements: This work was supported by MEXT as “Program for Promoting Researches on the Supercomputer Fugaku” (JPMXP1020200305) (Project ID: hp200128/hp210166/hp220167), and by JSPS KAKENHI Grant Number JP19H05703.
We have confirmed that the representation in the surface ocean is substantially improved in the high-resolution coupled model compared with a lower-resolution model in which the ocean resolution is 0.25 degrees. In winter, surface wind convergence and precipitation are intensified near the sea-surface temperature (SST) front along the Kuroshio and ocean eddies. In summer, rapid cooling of SST is clearly identified after the passage of typhoons. The signature of the typhoons lasts 10 days and more. The Kuroshio is also cooled due to the typhoons, but it recovers rapidly to the original high SST. This is an unprecedented opportunity to investigate the role of mesoscale air-sea interaction on the global climate system.
Acknowledgements: This work was supported by MEXT as “Program for Promoting Researches on the Supercomputer Fugaku” (JPMXP1020200305) (Project ID: hp200128/hp210166/hp220167), and by JSPS KAKENHI Grant Number JP19H05703.