Global Distribution of Convection in Tropical Cyclones Based on 11 yr of TRMM Data

The Tropical Rain Measuring Mission (TRMM) satellite has observed more than 900 tropical cyclones since its launch in late 1997. The unique suite of instruments, including Precipitation Radar (PR), TRMM Microwave Imager (TMI), Lightning Imaging Sensor (LIS), and Visible/Infrared Scanner (VIRS), allows examination of convective characteristics of these storms. Over 0.1 million Tropical Cyclone related Precipitation Features (TCPFs) have been identified from the 11 year University of Utah TRMM Precipitation Feature (PF) database. In this study, we use the TCPF database to generate the global distribution of convection in tropical cyclones. The common properties of convection in tropical cyclones are examined from a global perspective. The geographical, diurnal, and seasonal variations of convective proxies are presented. These proxies include the radar reflectivity profile, maximum height of 20 dBZ echo, minimum brightness temperature in IR and passive microwave channels (37 and 85 GHz), flash rate, etc. Features over land and over ocean are compared. The composite distributions of convective properties as a function of storm intensity and intensity change are examined. Examples of extremely intense convective events are presented to compare them to the composite distributions and to explore their potential significance to the evolution of the storms in which they appear.