Observation of cumulonimbus cloud growing process using Himawari-8

Abstract:

Recent years, Heavy rain falls caused disasters in Japan. Most of them were caused by mesoscale cumulonimbus cloud. To adapt these disasters and manage sustainable society, real-time and wide-area cumulonimbus cloud surveillance system is nessessary. In this study we aim to apply multi-band method of Himawari-8, a Japanese meteotological satellite, on interpretation of internal physical characteristics of multiple cumulonimbus clouds and discuss its status on image classification.

Day Convective Storm RGB image (DCS) is used for cloud-type classification. In this research, DCSs were generated from Himawari-8 data, and then defined cumulonimbus cloud area via unsupervised image classification based on maximum likelihood method. Time series analysis was carried out.

Our result shows that red component indicates cloud height and green component indicates convection strength turned upper to down. It means that cumulonimbus cloud turned growing to declining.About blue component which indicates cloud particle phase, two time-series trends were identified, which suggest a collision-coalescence process and a coagulation process.

This study suggests a possibility to observe cumulonimbus cloud growing process by using Himawari-8 data.