• Remote sensing of cloud and precipitation
  • This research is to improve our understanding of clouds and precipitation. The main tool is the event based database summarizing the properties of cloud and precipitation observations from spaceborne radars including CloudSat cloud radar, and TRMM precipitation radar. With this database, we can easily find out the severe weather events around the globe and study their properties.

  • Relationship between lightning and properties of storms
  • It is known that not all raining clouds have lightning strikes. In fact, shallow warm rain systems over oceans can never generate a lightning strike. This research topic is to understand the mechanism of lightning generation due to the ice processes in the intense convective clouds. Because storms are certainly not born equal, there are large regional variations of storms in different seasons and even at different times of day that have very different lightning rates. Another topic is to understand the relationship between the electric current on the top of electrified cloud systems and their counter part fair weather current in the global electric circuit.

  • Study of processes in the upper troposphere and the lower stratosphere
  • While the troposphere is warming up abnormally during the past century, the stratosphere is cooling down. To find out the reason, it is important to understand the physical processes of air transport between the troposphere and the stratosphere, which is still largely under debate. This reseach topic utilizes the satellite remote sensing and ground in-situ observations of the trace gases in the upper troposphere and the global convective systems to understand the role of deep convection in the vertical transport of the trace gases in the tropics and subtropics.