Diurnal Patterns of Precipitation Events in Sichuan Province
Heavy precipitation is an important trigger for mountain floods in Sichuan Province,and its diurnal varia-tion characteristics are the scientific support for mountain flood disaster defense.Based on the hourly precipitation data of 6 725 stations,spatial zoning and time segmentation were used to study the diurnal variation and spatial characteristics of precipitation in Sichuan Province.The overall precipitation distribution in Sichuan Province can be divided into three types:nighttime(western mountains),early morning(south Sichuan),and daytime(north Sichuan).Short-duration precipitation events are frequent,and 1-3 h precipitation occurs mostly in the early morning and afternoon.However,long-duration(>3 h)precipitation occurs more in the early morning.The peaks of precipitation events are mostly present in the early morning(>62%),and the peak of the precipitation in the early morning often appears within 5 hours.The start time of the precipitation events advances with the increase of altitude.This study indicates that the mountains a-round the Sichuan Basin have frequent and intense precipitation at night,and the risk of mountain flood disasters caused by strong nighttime precipitation events should be carefully accounted.
hydro-meteorologyprecipitation eventdiurnal variationnight rainstorm flashSichuan Province
万方数据
维普
