Vertical Distribution of Radar Reflectivity Factor in Intense Convective Clouds over Indonesia

Abstract

Vertical distribution of intense convective clouds over Indonesia has been studied using radar reflectivity factor (dBZ) data gathered from the latest 2A25 TRMM–Precipitation Radar (PR) product over a 10-year (1998–2007). The vertical distribution of dBZ at the PR pixel scale has been classified into two type of convective cells, i.e., cumulonimbus tower (CbT) and intense convective clouds (ICC) following the classification proposed by some previous studies. The CbT contains Z threshold 20 dBZ at 12 km altitude with at least 9 km deep and the ICC contains Z threshold 30 and 41 dBZ at 8 and 3 km, respectively. It is found that intense convective cloud is more frequently observed over land such as Sumatra, Kalimantan and Jawa than over ocean areas. Downward increasing (DI) pattern of dBZ toward the surface found in CbT over coastal area of Sumatra and Indian ocean. ICC8 and ICC3 shows downward decreasing (DD) pattern for all locations.


 


 


Keywords: radar reflectivity, intense convective clouds, Indonesia, TRMM-PR 2A25

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