Comparison of vertical structures of Hurricanes Typhoons and Cyclones as observed by Spaceborne Precipitation Radar

摘要

Precipitation radar (PR) on Tropical Rainfall Measuring Mission (TRMM) satellite offers three-dimensional downward-looking observations of tropical storms. Such observations are very useful to study the structure of tropical storms. This work presents a systematic study of vertical profile of reflectivity (VPR) of hurricanes over North Atlantic, typhoons over North Western Pacific and cyclones over South Indian Ocean. Due to a large number of VPR observation, it is possible to classify them into characteristic profiles so that it can be useful in comparing different structures. In this study, Self Organizing Map (SOM) is used to classify VPR of hurricanes, typhoons and cyclones observed in the years 2000, 2002 and 2003. We have not included the 2001 data because of the orbit transition during that year. More than 100 storms are studied in this work. VPR of the storms are classified into characteristic profiles. Percentages of contribution of each characteristics profile are determined. In addition the microphysical structure including drop size and its concentration is also derived. Comparative study on yearly basis of hurricanes, typhoons and cyclones reveals similarities and systematic differences among them, and those results are presented.