Abstract
This paper reviews the basis of passive microwave algorithms that derive rainfall rates directly from relationships between brightness temperatures and rainfall rates established by statistical relationships and empirical calibration. The performance of these algorithms and their present and future roles are assessed in comparison with the increasing number of modeling techniques used for passive microwave rainfall retrievals.
Corresponding author address: Dr. C. Kidd, Universities Space Research Association, NASA/Goddard Space Flight Center, Code 912.0, Greenbelt, MD 20771.