A series of eddy-resolving ocean simulations in the world ocean - OFES (OGCM for the Earth Simulator) project

Abstract

Ocean general circulation models (OGCMs) have long been used to investigate oceanic circulations and their variation with various spatial and temporal scales. Mesoscale eddies, which diameters are about 100 km, should be resolve in order to reproduce not only basin-scale circulation but also eddy activities and proper path of western boundary currents. They also play an important role to meridional transport of heat and momentum. Recently, an eddy-resolving OGCM simulation with 0.1/spl deg/ horizontal grid spacing in the North Atlantic basin suggests that OGCM should have the grid spacing of the order of 0.1/spl deg/ or finer. Although computational resource was not enough to execute global eddy-resolving simulation, the Earth Simulator (ES) with 40 Tflops peak performance, which currently is the fastest massive parallel computer for general purpose, changed the computational environment. The ES and OGCM highly tuned for the ES provide us the opportunities to execute several decadal integrations of the eddy-resolving OGCM simulation in the global domain. In This work, successful outcomes and advanced visualizations from a series of eddy-resolving simulations in the world ocean: a 50 year spin-up run, hindcast run from 1950 to 2003 and tracer run incorporated with chlorofluorocarbons (CFCs), are reported.