Spatiotemporal characteristics of extreme precipitation events with different durations in Shandong Province from 1981 to 2023

Minute-by-minute precipitation data from 101 national meteorological stations in Shandong Province from 1981 to 2023 were analyzed to investigate the spatiotemporal variation characteristics of annual maximum precipitation with different durations.Results show that the spatial distributions of mean annual maximum precipitation and their extreme values for different durations are inconsistent across Shandong Province.The mean annual maximum precipitation predominantly occurs in the central-eastern areas of southern Shandong,with spatial differences increasing with duration.The spatiotemporal distribution patterns of annual maximum precipitation changes are generally consistent across different durations,with most regions showing increasing trends.The center of annual maximum precipitation intensity shifts eastward as duration increases,exhibiting a significant increasing trend in interdecadal variation,with amplitude increasing with duration.The annual maximum precipitation of different durations occurs most frequently in July,predominantly in the afternoon; its extreme values mostly appear in July and August,commonly occurring between afternoon and early morning.After 2011,33%-52% of stations recorded historical extreme values for annual maximum precipitation of different durations.