Developing coupled ocean-atmosphere global climate model for the Earth simulator and its computational/physical validation

Coupled global climate model (CGCM) provides a very powerful tool to reproduce the main features of the observed climate. Although the great expense of running CGCM has been a hindrance in development by limiting the number of calculations, the resources of the Earth Simulator may be able to carry out such a huge scale simulation. Our objective here is to introduce coupled global climate models for the Earth Simulator (CFES) with ultra-high resolution to carry out a century of integration within a reasonable time. It is composed of an oceanic general circulation model for the Earth Simulator (OFES) and an atmospheric general circulation model for the Earth Simulator (AFES). We provide a new coupling structure to transfer physical data from one component model to the other component through a coupler and back again. In the structure of a parallelized coupling scheme, each component can run independently to avoid drift due to feedback timing. Due to the parallelization, CFES was also able to control concurrent performance by changing the number of nodes which employed components of atmospheric and oceanic models. In addition, we will show that the interpolation scheme introduced in this coupler conserves the physical values well.