资源环境科技发展态势分析平台

Based on unprecedented 22-year records from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) and the Global Precipitation Measurement (GPM) dual-frequency precipitation radar (DPR), this study aims to investigate the global distribution and linkage between both convections and precipitation extremes quasi-globally. Overall, the spatial distributions of extreme events show significant regional variability and land-ocean contrast. Extreme precipitation is dominant over tropical ocean while extreme convections are exclusive over land from tropics to higher latitude. Besides, there are strong positive relationships between extreme convections and precipitation based on multiple threshold-based definitions of extremes, which provides more consistent physical properties of extreme events globally. The correlation is significant over land but relatively weak over oceans. Seasonal occurrences of extreme events are also examined. Furthermore, extreme events exhibit notable diurnal characteristics over global land with most extreme convections occurring in the afternoon, while diurnal cycles are more homogeneous over ocean.

Plain Language Summary Extreme rainfall and convection events are of significant social interest due to their close linkage with a variety of natural hazards, while the two types of events are used too interchangeably in literature. To document the spatial variability and linkage between extreme convections and extreme precipitation, we use 22-year records from the precipitation radar onboard Tropical Rainfall Measuring Mission satellite and the dual-frequency precipitation radar onboard Global Precipitation Measurement satellite. Threshold-based definitions of extremes are used. Results show that the correlation between extreme convections and precipitation is strong over land, while ocean region shows a little weaker association from tropics to higher latitudes. The occurrences of extreme events show notable seasonal variations and exhibit a significant peak in the afternoon.