10-km Mesh Meso-scale Resolving Simulations of the Global Atmosphere on the Earth Simulator - Preliminary Outcomes of AFES (AGCM for the Earth Simulator) -

Abstract

In early March of 2002, a massively-parallel-vector supercomputer, the Earth Simulator, came into operation, providing a unique opportunity to perform simulations of the general circulation of the global atmosphere with horizontal resolution of about 10 km. We employ a general circulation model called that has been fully optimized to the unique architecture of the Earth Simulator, to attain extremely high com- putational efficiency. The ultra-high resolution global simulations with AFES are able to explicitly represent interaction among planetary, synoptic and meso-scale phenomena and the topographic modulation of mesoscale precipitation without the need to nest a regional mesoscale model. Examples are presented of win- tertime extratropical cyclogenesis in the North Pacific, a polar low over the Sea of Japan, pre-summer Baiu frontal zone over Japan and typhoon evolution over the western North Pacific, to show that mesoscale precip- itation systems and their interactions with synoptic and planetary scale flows and topography are indeed sim- ulated in a fairly realistic manner. Filamentary evolution of potential vorticity within an upper-level trough and its coupling with the underlying frontal evolution or polar-low development are also simulated.