Analysis of the Structural Characteristics and Intensity Evolution of SuperTyphoon Flo (1990) in Special Sensor Microwave/Imager (SSM/I) Data

摘要

The purpose of this research has been to observe and analyze the structuraldetails and intensity evolution of Super Typhoon Flo (1990) using SSM/I data. Flo's structural characteristics were observed with SSM/I imagery and then compared with conventional, infrared and visible satellite data to illustrate qualitative distinctions between the two types of data. High resolution 85-0hz imagery showed more convective detail than operational line scan (OLS) data while low resolution 19-0hz data afforded more realistic analysis of the active tropical cyclone region when compared with 0MS data. Center locations determined in horizontally polarized 85-0hz imagery offered improvement over the OLS fixes obtained from corresponding DMSP passes. However, the SSM/I derived 85 and 19-0hz retrieval statistics, employed as intensity indicators in previous tropical cyclone research, were poorly correlated with changes in Flo' 5 intensity. Two over ocean SSM/I rainfall rate retrieval algorithms were compared for accuracy. The more accurate algorithm employing the 85-0hz frequency was used to characterize Super Typhoon Flo's rainfall rate distribution and intensity evolution. Results are generally similar to previous studies. Maximum rainfall rates were usually confined to the eyewall and inner-core region. Furthermore, changes in Flo's average inner-core rainfall rate correlated reasonably well with intensity changes. (MM).