Research on monitoring and early warning methods for extreme thunderstorm and strong wind events in Liaoning Province using the FY-4A satellite

By utilizing the data from the infrared and water vapor channels of the FY-4A satellite, as well as the reanalysis data from the European Centre, we conducted a study on the identification method of convective cloud clusters during three different severe thunderstorm wind events. Based on the characteristics of convective cloud clusters observed by the satellite, we selected cloud cluster feature parameters that have significant early warning implications. We then performed parameter calculations and feature analysis on the identified convective cloud clusters. The conclusion is as follows: The multichannel threshold method has been improved by adding a parameter for the tropopause temperature. This method allows for a clearer observation of the uneven development of convective clouds. It can also clearly identify the center of strong updrafts within convective clouds. As the convective clouds rapidly develop, the infrared brightness temperature decreases rapidly, with a minimum brightness temperature below 220K. The convective clouds begin to intensify. Intense updrafts penetrate the tropopause, with cloud top temperature significantly lower than the tropopause temperature. The maximum brightness temperature gradient within the cloud is located at the leading edge of cloud clusters.