Passive Microwave Sensor detecting tropical storms

The TRMM Microwave Imager (TMI) is employed to observe and measure tropical rainfall using information from nine passive microwave channels. These channels are sensitive not only to rainfall but also to clouds, water vapor, ice, surface moisture, and snow cover, among other variables. These other variables are a noise source in the retrieval of precipitation. Petty (2012; submitted) has devised a dimensional reduction algorithm that filters out much of the background noise while retain much of the precipitation information in the form of three so-called pseudochannels, which are constructed as linear combinations of the original nine channels. The purpose of the present work is to investigate the nature of the physical information about storm structure contained in each of the pseudochannels and to examine their combined utility in revealing subtle differences between precipitating cloud systems in different environments.