Parametrizing Convection Using Satellite-Retrieved Precipitation Profiles

Florida State University, Tallahassee FL

Investigators

Abstract

The main focus of the research is to develop an empirical cumulus parameterization scheme that exploits high-resolution, in space and time, precipitation and hydrometeor profiles from a new era of satellites. The work involves a sequence of research steps. Microwave (three hourly) and infrared radiance (thirty minutes) data sets will be used to track convective systems. A split-step advection/convection procedure will be used to track these systems. Another aspect of the research is the construction of vertical profiles of heating and drying from the generated thirty-minute data sets. This is followed by the formulation of relationships among convective available potential energy and the vertical profiles of heating/drying, forming the basis for the new cumulus parameterization scheme. Some of the recent field experiments will be used which provide an opportunity for the model validation of heating/drying (i.e., Q1, Q2 fields) and for the optimization of the overall scheme. Intellectual Merit: The PIs will develop: (1) a high-resolution data base and construct vertical profiles of apparent heat source and moisture sink for use in cumulus parameterization schemes, and (2) an empirical cumulus convection parameterization scheme for use in general circulation models. Broader Impacts: The research results will help to minimize the systematic errors in cumulus parameterization schemes and improve medium-range and seasonal forecasts of precipitation, leading to a better understanding of dry/wet spells and floods/droughts.