Optical Properties and Spatial Variation of Tropical Cyclone Cloud Systems From TRMM and MODIS in the East Asia Region: 2010–2014

Abstract

AbstractThe tropical cyclone (TC) in East Asia varies strongly each year, indicating the different spectral characteristics of the TC cloud systems (TCCSs) with the distance from the center of TC. We report a new perspective of optical properties of TCCS by using the Moderate Resolution Imaging Spectroradiometer and Tropical Rainfall Measuring Mission data over the years from 2010 to 2014 for the 35 TCs in East Asia. We investigate the spatial distribution of the cloud‐top height, radar reflectivity, polarization corrected temperature in 85.5 GHz (PCT85.5), hydrometeor vertical profile, cloud water path, cloud optical thickness, and cloud particle effective radius of TCCS in the development, maturity, and decay stages of TC. The results indicate the significant differences of cloud characteristics in the maturity stage in comparison to other two stages, showing the higher radar reflectivity up to 30 dBZ and the PCT85.5 as low as 232.98 K in the TC eye wall. Meanwhile, the mean hydrometeor profile indicates more ice particles accumulating above the height of 10 km but less liquid droplets near 3 km. The peak of cloud water path and cloud optical thickness in the maturity stage can reach to 1,300 g/m2 and 75, respectively. The mean cloud particle effective radius and precipitation in the three stages could be influenced by aerosols. Based on these quantified results, several ideal fitting equations and the models are constructed to denote the properties of TCCS. Two cases are analyzed to examine the accuracy of the quantified mean state for different stages of TCCS and the relationship between aerosols and clouds.