Ice-phase Precipitation Retrievals over Land Using Combined Radar / Radiometer Satellite Observations

Passive microwave (PMW) measurements of ice-phase precipitation, such as snowfall and graupel, provide a physically direct basis for inferring the integrated amount of precipitation within a given field-of-view (FOV), assuming that other sources of noise can be adequately accounted for. However, the vertical distribution of precipitation within the FOV is generally unknown. By combining passive observations with co-located satellite-based radar observations, then we can begin to estimate the vertical distribution of precipitation and simultaneously improve the retrieval uncertainty compared to passive microwave alone. The present research describes the development of a retrieval algorithm for use with the upcoming Global Precipitation Measurement (GPM) mission, which will have co-located dual wavelength radar and radiometer observations available for nearly global precipitation observations.