近32 a山东不同地区短时强降水时空分布和环境参数特征OA

This study utilizes hourly precipitation data from 122 national ground meteorological stations in Shandong,covering the period of 1991 to 2022,in conjunction with the ERA5 reanalysis data developed by the European Centre for Medium-range Weather Forecasts(ECMWF),to investigate the spatiotemporal distribution and environmental characteristics of Short-duration Heavy Rainfall(SDHR)in Shandong Province.It is found that Shandong's diverse topography results in distinct characteristics of SDHR across different regions.The northwestern Shandong region(plain)has the highest contribution rate of SDHR to the total precipitation.In the southeastern Shandong region,which is located on the southern flank of the central Shandong mountainous area,SDHR exhibits high annual frequencies and extreme precipitation intensities.SDHR in the central-northern Shandong region shows the characteristics opposite to that in the southeastern Shandong region.The frequency and intensity of SDHR precipitation in the southern part of the Shandong Peninsula are significantly higher than those in the northern part.SDHR in Shandong shows relatively distinct diurnal variation characteristics.The station-averaged SDHR frequency peaks primarily occur in the early morning and late afternoon,with the exception of the southern Shandong region.The rainfall amounts for extreme SDHR events during the nighttime are significantly greater than those during the daytime.Different regions in Shandong exhibit distinct seasonal characteristics in SDHR.In spring,extreme SDHR events are mainly located in the central and northern parts of central Shandong as well as certain areas in southern Shandong,while in autumn,extreme SDHR events are predominantly found in the peninsula region.Water vapor parameters are significantly indicative of the occurrence of SDHR in Shandong.850 hPa specific humidity,precipitable water vapor,and K index can be used as a reference for SDHR in Shandong during July and August.Dynamic parameters alone cannot serve as favorable conditions for SDHR.A comprehensive analysis must be conducted in conjunction with water vapor parameters and thermodynamic parameters.