Passive Microwave Satellite Observations of Cloud Liquid Water Path: Uncertainty Datasets and Validation

Cloud liquid water path (CLWP) observations from passive microwave (PMW) sensors are underutilized in climate studies mainly because they have undergone very limited validation and lack information on their inherent errors. This project, supported by the NASA MEaSUREs (Making Earth System Data Records for Use in Research Environments) Program, provides the first comprehensive dataset of the inherent systematic errors in PMW CLWP observations and the most extensive validation to date of these observations. These uncertainties are strictly for warm oceanic clouds over the 9-yr record of the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and are specific to the latest (Version 7) Remote Sensing Systems CLWP products. Errors were estimated from a multi-sensor analysis using collocated MODIS, Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and CloudSat Cloud Profiling Radar (CPR) observations, which include Level 2 (swath) and Level 3 (binned, monthly mean) uncertainty datasets. High-quality validation datasets are obtained from ship-based (German RV Polarstern and NOAA RV Ronald H. Brown cruises) and Atmospheric Radiation Measurement (ARM) island-based microwave radiometer observations in the Atlantic and Pacific oceans over multiple years.