The Influence of Cumuli Distribution in Satellite Microwave Radiometer FOV on the Accuracy of Atmospheric Moisture Content Retrieval

The article explores systematic errors in atmospheric moisture content parameters microwave radiometric retrieval. The errors under consideration arise due to the nonlinearity of brightness temperature (BT) level on liquid water and effective cloud temperature dependencies, and due to neglecting the spatial distribution of cumulus clouds in the satellite microwave radiometer antenna field-of-view (FOV). It is shown that when liquid-drop moisture is assumed to be uniformly distributed over the FOV area, a systematic underestimation of FOV-averaged liquid water content (LWC) and an overestimation of total water vapor (TWV) are observed as the result of retrieval. An attempt is made to relate specific statistical parameters, which describe spatial distributions of inhomogeneous cloudiness observed in an atmospheric cell, with TWV and LWC errors arising from this assumption.