An eddy-resolving hindcast simulation of the quasiglobal ocean from 1950 to 2003 on the Earth simulator

An eddy-resolving hindcast experiment forced by daily mean atmospheric reanalysis data covering the second half of the twentieth century was completed successfully on the Earth Simulator. The domain covers quasiglobal from 75 degrees S to 75 degrees N excluding arctic regions, with horizontal resolution of 0.1 degrees and 54 degrees vertical levels. Encouraged by high performance of the preceding spin-up integration in capturing the time-mean and transient eddy fields of the world oceans, the hindcast run is executed to see how well the observed variations in the low- and midlatitude regions spanning from intraseasonal to decadal timescales are reproduced in the simulation. Our report presented here covers, among others, the El Nino and the Indian Ocean Dipole events, the Pacific and the Pan-Atlantic decadal oscillations, and the intraseasonal variations in the equatorial Pacific and Indian Oceans, which are represented well in the hindcast simulation, comparing with the observations. The simulated variations in not only the surface but also subsurface layers are compared with observations, for example, the decadal subsurface temperature change with narrow structures in the Kuroshio Extension region. Furthermore, we focus on the improved aspects of the hindcast simulation over the spin-up run, possibly brought about by realistic high-frequency daily mean forcing.