MULTI-SATELLITE OBSERVATION OF MEGH CYCLONE

Abstract

Cyclone Megh, a category-3 (Saffir-Simpson scale) cyclonic storm is regarded as the worst tropical cyclone to ever strike Yemen’s island of Socotra. In this paper, we aim to investigate the wind structure of cyclone Megh using Synthetic Aperture Radar (RISAT-1 SAR) observations. An algorithm for the cyclone wind retrieval has been applied for SAR data of Nov 8, 2015 at 0238:09 UTC in the Arabian Sea. The intensity of cyclone is 30 m/s with the 16.65 km radius of maximum wind speed from the centre of the cyclone. The high resolution SAR data analysis bring to focus the possible presence of eyewall mesovortex in case of Megh. Recent work has shown that vorticity mixing in the tropical cyclone (TC) inner core can promote mesovortex (MV) formation and impact storm intensity. This has further been corroborated using INSAT-3D and MODIS optical band observations of clouds. Analysis of these satellite derived cloud microphysical properties shows the presence of larger hydrometeors surrounding the eye due to possible embedding of stratus and stratocumulus cloud decks. Thus, this kind of study helps in understanding the microphysical processes within a TC as well estimating their impacts on cyclone intensity and lifetime.