Impacts of model resolution on simulation of meso-scale eddies in the Northeast Pacific Ocean

Abstract

The model simulated meso-scale eddies in the Northeast Pacific Ocean, using two models with nominal horizontal resolutions of 1/12° and 1/36° in latitude/longitude (grid spacing of 7.5 km and 2.5 km), respectively, are presented. Compared with the 1/12° model, the 1/36° model obtains (1) similar variance and wave number spectra of the sea level anomaly and water temperature anomaly, and (2) increases in the level of the domain-averaged total kinetic energy, eddy kinetic energy (EKE), and variance of horizontal gradient of water temperature. In the interior basin of the southern region, both models show stronger eddy frontal activities, represented by EKE, temperature and its horizontal gradient, in summer and fall than in winter and spring. The challenge of evaluating the realism of highresolution ocean models with conventional satellite remote sensing observations is discussed.