Global Changes in Precipitation Concentration Through Consecutive Event Organization

Abstract

Global warming is reshaping precipitation extremes and increasing temporal rainfall unevenness, yet precipitation unevenness has rarely been quantified at the scale of consecutive precipitation events. Using daily observations from 19,183 gauge stations worldwide during 1980–2022, we defined WE50 as the total duration of the consecutive wettest precipitation events required to deliver 50% of annual precipitation, and WE50_event as the number of selected events contributing to that half. The global mean WE50 is 27.8 days, and WE50_event is 9.4 events, with Europe exhibiting the largest values. Trend analyses show that WE50 decreases significantly at 45.7% of global stations, whereas WE50_event changes are generally weak. A decomposition further indicates that the global WE50 decline is largely attributable to shorter durations of consecutive precipitation events, with comparable contributions observed in Europe and South America, whereas regional differences emerge in the contributions of precipitation amount, event intensity, and duration.