Determination of Ice Water Path in Ice-Over-Water Cloud Systems Using Combined MODIS and AMSR-E Measurements

Most satellite cloud retrievals are based on the assumption that all clouds occur in a single layer. But multi-layered clouds are common, often yielding retrieved values between those for the two separate layers. In this study, the multilayered cloud retrieval system (MCRS) is used to retrieve ice water path in ice-over-water cloud system over global ocean. Liquid water path (LWP) of lower layer water clouds are estimated from Aqua Advanced Microwave Scanning Radiometer for EOS (AMSR-E) measurements. When the lower-level LWP is constrained, the properties of upper level ice clouds are then derived from a comparison of satellite visible measurements with simulated radiances of the two layer clouds model. The results suggest that the MCRS can significantly improve the accuracy and reduce over-estimation of optical depth and ice water path (IWP) retrievals for ice-over-water cloud systems.