comprehensive study of tropical storms as observed by TRMM

Presentation Type: 
V. chandrasekar (colorado state university)

Precipitation Radar (PR) onboard Tropical Rainfall Measurement Mission (TRMM) satellite launched in November 1997, is the first of its kind that has been globally monitoring tropical storms from space. Capability of PR in providing high vertical resolution measurement makes it possible to study vertical structure and associated microphysics of tropical storms. Total of 439 tropical storms (100 hurricanes in the North Atlantic, 213 typhoons in the North Western Pacific and 126 cyclones in the South Indian Ocean) observed over year 2000 to 2013 were comprehensively studied. Self Organizing Map (SOM) technique was used in classifying attenuation-corrected vertical profile of reflectivity (VPR) into a specified number of characteristics VPR (CVRP). SOM classification forms a basis of CVPR used for comparative study. Comparison on yearly basis reveals systematic differences and similarities of CVPR strength among storms. Intensity of rainfall rate produced by hurricanes, typhoons, cyclones were exhibited in the context associated with CVPRs. Overall variations of rainfall rate over the years produced by the tropical storms are illustrated by cumulative distribution curves. Rain drop size distribution (DSD) parameters were estimated. The estimated DSD was compared with those proposed in the literatures. It was found that intense rainfall rates were associated with large concentration of smaller drops. When calculated DSD parameters were associated with CVPRs, rain drops with relatively large diameter was found to relate to very tall CVPR. In addition the DSD parameters mapped on a snap shot of tropical storm cells shows that large drops present mostly in eye wall of storms.

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