How often does it rain over the global oceans? The perspective from CloudSat

The frequency of precipitation occurrence over the global oceans from 2006 – 2007 as calculated from CloudSat radar data is compared to ship-based (ICOADS) and islandbased (GSOD) data. It is shown that the spatial pattern of the precipitation frequency from CloudSat is consistent with previous climatological studies. The comparison to shipbased data reveal that CloudSat results are consistent with ship observations well into the high latitudes and appear to capture the seasonal cycle of precipitation well. A comparison to island data also shows good qualitative agreement, although the spatial scale mismatch complicates the efficacy of such comparisons. Nevertheless, CloudSat is shown to be a viable platform for obtaining quality satellitebased precipitation frequency measurements.