Analysis of observation characteristic of FY-3 microwave hygrometer during an extreme short-term heavy precipitation process

Abstract

Based on data of FY-3 satellite microwave hygrometer and conventional observation, microwave observational characteristics of convective clouds during a heavy precipitation event from Giuzhou to Hubei province in 2016 were analyzed. The results show that (1) The brightness temperature at the window channel near 150 GHz over an extreme short-term heavy rainfall station is lower than that of the non-extreme short-term heavy rainfall station. (2) The brightness temperature vertical distribution at water vapor absorption channel is fun-nel-shaped over the extreme short-term heavy rainfall station, which is a certain indication of dry invasion. The lowest brightness tempera-ture occurs near 183.31±7 GHz, indicating warm cloud precipitation. However, the brightness temperature vertical distribution at water va-por absorption channel is vertical-bar shaped over the non-extreme short-term heavy rainfall station. The lowest brightness temperature oc-curs near 183.31±3 GHz and 183.31±7 GHz, indicating precipitation of mixed cold and warm clouds. (3) There is no topping convection over extreme short-term heavy rainfall stations, but the low-level convection develops vigorously. Top-rushing convection appears over non-extreme short-term heavy rainfall stations, but the intensity of low-level convection is weak.

Keywords

• fy-3 microwave hygrometer
• extreme short-term heavy rainfall
• flush convection
• dry intrusion