A Census of Precipitation Features in the Tropics Using TRMM: Radar, Ice Scattering, and Lightning Observations

作者：Stephen W. Nesbitt, Edward J. Zipser, Daniel J. Cecil · 发表于：Journal of Climate · 年份：2000 · DOI：10.1175/1520-0442(2000)013<4087:acopfi>2.0.co;2 · 被引用次数：455 · 研究领域：Precipitation Measurement and Analysis、Meteorological Phenomena and Simulations、Atmospheric aerosols and clouds

An algorithm has been developed to identify precipitation features (≥75 km2 in size) in two land and two ocean regions during August, September, and October 1998. It uses data from two instruments on the Tropical Rainfall Measuring Mission (TRMM) satellite: near-surface precipitation radar (PR) reflectivities, and TRMM Microwave Imager (TMI) 85.5-GHz polarization corrected temperatures (PCTs). These features were classified by size and intensity criteria to identify mesoscale convective systems (MCSs), precipitation with PCTs below 250 K, and other features without PCTs below 250 K. By using this technique, several hypotheses about the convective intensity and rainfall distributions of tropical precipitation systems can be evaluated. It was shown that features over land were much more intense than similar oceanic features as measured by their minimum PCTs, maximum heights of the 30-dBZ contour, and 6-km reflectivities. The diurnal cycle of precipitation features showed a strong afternoon maximum over land and a rather flat distribution over the ocean, quite similar to those found by others using infrared satellite techniques. Precipitation features with MCSs over the ocean contained significantly more rain outside the 250-K PCT isotherm than land systems, and in general, a significant portion (10%–15%) of rainfall in the Tropics falls in systems containing no PCTs less than 250 K. Volumetric rainfall and lightning characteristics (as observed by the Lightning Imaging Sensor a...