Tropical oceanic cloudiness and the incidence of precipitation: Early results from CloudSat

Results of analysis of CloudSat radar data collected during the first three months of operation are described. It is shown that the global tropical oceans (30N – 30S) predominantly favor clouds with tops in two layers centered at about 2 and 12 km. Precipitating clouds occur primarily in three modes, a shallow mode that is the most frequent type, as well as a middle and deep mode. Regional features are also discussed. The Indian and western Pacific Oceans exhibit more predominantly high clouds and deeper precipitation features than the eastern Pacific and Atlantic. The occurrence of a mid-level mode of cloudiness and precipitation is shown to vary regionally, being particularly significant in the western Pacific. For all regions examined, precipitating clouds are observed to be deeper than nonprecipitating clouds. Over the global tropical oceans, 18% of the clouds detected by CloudSat produce precipitation.