Deep Convective Cloud Identifications from both Broadband and Hyperspectral Infrared Measurements

Deep convective weathers have contributed to several flight accidents through aviation history, becoming a threat to the aviation safety. The most common method to identify deep convective clouds (DCCs) is using the brightness temperature difference (BTD) between the atmospheric infrared window (IR) channel and the water vapor absorption (WV) channel from weather satellite measurements. In this study, the brightness temperatures over DCCs of the QZ8501 case are simulated by RTTOV with simple cloud scheme for both broadband (MTSAT-2 imager) and hyperspectral (Atmospheric Infrared Sounder, AIRS) instruments. The simulation shows that although broadband IR imagers onboard the geostationary satellites have finer spatial resolution and smaller NEΔT, the uncertainty in the DCC identification is larger compared with hyperspectral IR sounders. BTD measured by a hyperspectral IR sounder also has the potential to estimate the cloud top height for DCCs.