Tropical precipitation rates during SOP-1, FGGE, estimated from heat and moisture budgets

Abstract This study presents global estimates of precipitation rates from 30°N to 30°S, derived from the “apparent” heat source (Q1) and “apparent” moisture sink (Q2) budgets using the NASA Goddard Laboratory for Atmospheres Level III-b analyses collected during the first special observing period (SOP-1) of the Global Weather Experiment. In each technique precipitation is solved as the residual. Because of the assumptions made, the techniques yield the most reliable results in the summer hemisphere. Therefore, area averages of precipitation rates are presented to examine the variability of rainfall among selected regions in the Southern Hemisphere tropics. These regions include Africa, the Indian Ocean, the Australian monsoon, the South Pacific convergence zone (SPCZ), and the South American/South Atlantic convergence zone (SACZ). Time averages of precipitation rates are also calculated for two periods (10–24 January and 28 January–11 February 1979) that were selected because of significant changes observ...