Structure of Deep Convection During TRMM TEFLUN and LBA Campaigns Observed With Airborne and Ground-Based Polarization Radar

The Tropical Rain Measuring Mission (TRMM) conducted several field campaigns for validation of the satellite-derived rain measurements and for improved understanding of precipitation processes. Two of these campaigns, TEFLUN-B in Florida and TRMM-LBA in Brazil Amazonia, are the subject of this paper. The ER-2 Doppler Radar (EDOP) mounted on the high-altitude ER-2 aircraft collected data from deep convection cases that were also sampled by the ground-based NCAR S-Band Polarization Radar (S-POL). EDOP's dual-fixed-beam Doppler measurements provide vertical and along-track hydrometeor motions and derived vertical velocities. The purpose of this paper is present and discuss two deep convective cases, one in Florida on 18 August 1998, and the other in Brazil on 10 February 1999. Earlier work by one of the co-authors (Tian) examined the attenuation and polarization structure for these cases, from which it was concluded that drop sizes were generally smaller in Brazil than in Florida. This paper focuses on comparing the wind fields derived from EDOP with the previously derived S-POL-derived microphysical structure. The two cases have markedly different wind shear profiles resulting in structural differences of the storms. The Brazil storm has a strongly sloped updraft, peak vertical velocities approximately 10 m/s, and an absence of large ice hydrometeors. The Florida storm has stronger updrafts, weaker tilt, and the presence of larger ice hydrometeors. Implications of the measurements on the kinematics and microphysics of the storms will be presented as well as the relevance of the work to spaceborne precipitation measurements from TRMM and future spaceborne radars.