While clouds play in critical role in regulating the energy budget of the earth-atmosphere system, representation of cloud properties and microphysical processes in current climate models remains…

This is a research grant awarded by the National Aeronautics and Space Administration (NASA) Shared Services Center to the University of Maryland, Baltimore County (UMBC) to develop a novel algorithm for retrieving ice water path and cloud-top height from combined passive infrared and microwave satellite observations. The goal is to generate long-term, consistent, and reliable global cloud records that can improve understanding of cloud representation in climate and weather models. The grant, valued at $133,263.85, does not have a set-aside designation and was awarded on June 24, 2020, with a completion date of July 25, 2023. UMBC, a public research university and part of the University System of Maryland (USM), has a history of providing research, measurement, and analytical services to support NASA programs through prime and subcontract awards.

While clouds play in critical role in regulating the energy budget of the earth-atmosphere system, representation of cloud properties and microphysical processes in current climate models remains one of the largest sources of uncertainty. Among numerous modeled cloud properties, cloud water path (CWP), especially ICE water path (IWP), shows significant large inter-model difference. One important reason for the large IWP uncertainty is the lack of robust and consistent observational constraints. Although current satellite instruments provide an unprecedented opportunity to observe global clouds, studies have shown that IWP retrievals from different satellite-based instruments can vary by a factor of 10. Additional complication may arise from using the inconsistent IWP records to constrain models. The proposed research intends to obtain a more comprehensive information for global clouds from combined passive infrared (IR) and microwave (MW) observations. A novel and robust algorithm will be developed to retrieve IWP and cloud-top height (CTH) for various satellite instrument combinations with simultaneous IR and MW observations. Long-term, consistent, and reliable global cloud records will be generated. The long-term and consistent CWP and CTH records will directly benefit a wide variety of research communities, improve our understanding of uncertainties in current cloud records, and provide a unique and valuable observational constraint for reproducing cloud microphysical processes and improving cloud parameterizations in climate and weather models.