FORECASTING IN THE TROPICS WITH A BAROTROPIC ATMOSPHERIC MODEL

Abstract A series of barotropic forecasts has been prepared for several upper-air levels in the tropical Pacific. The governing equation is the vorticity equation for a barotropic non-divergent atmosphere. The input data are stream-function values derived from an objective tropical wind analysis. The area covered is the Pacific Ocean Tropics of both the Northern and Southern Hemispheres. Examples of tropical barotropic forecasts are shown. Verification data suggest that these barotropic forecasts have slightly less accuracy than subjective forecasts.