Response of the NCAR General Circulation Model to North Pacific Sea Surface Temperature Anomalies

Abstract

Abstract The general circulation model (GCM) of the National Center for Atmospheric Research was used to investigate the effects of anomalous sea surface temperature (SST) patterns in the mid-latitudes of the North Pacific Ocean on atmospheric circulations. One of the most frequently observed SST anomaly (SSTA) patterns, a “cold pool” of water in the west and a “warm pool” in the cast (from 35 to 55°N) with magnitudes ±4°C of the temperature of the surrounding water, was superimposed on the seasonally varying oceanic temperature as the thermal boundary condition in the North Pacific of the atmospheric GCM for the anomaly experiment Three similar experiments, one the control, two the noise and three an exaggerated SSTA, were run simultaneously. Time integrations for all cases were carried out for 120 days, beginning on 15 January. Preliminary results indicate that cyclonic activities are strengthened above the warm SSTA and suppressed above the cold SSTA. A direct thermal circulation is induced in the vert...