Seasonal variation of eddy kinetic energy of the North Pacific Subtropical Countercurrent simulated by an eddy‐resolving OGCM

Abstract

The seasonal variation of eddy kinetic energy (EKE) of the North Pacific Subtropical Countercurrent (STCC) was investigated by analyzing the data from an eddy‐resolving OGCM with the horizontal resolution 1/12° in comparison with satellite altimetry data. Although the annual cycle of simulated EKE of the whole STCC domain showed agreement with satellite data, with a maximum in spring and a minimum in fall, it revealed latitudinal dependence; that is, near 19°N the EKE level is higher in summer than in winter, but it is higher in winter than in summer north of 20°N. The OGCM also reproduced two branches of the STCC, which affect the EKE variation. The variation of EKE level was shown to be closely related to the growth rate of baroclinic eddies. The simulated zonal velocity is much larger than climatological value, thus allowing much faster growth of baroclinic eddies.