1980-2020年山西省极端降水特征OACSTPCD

Based on the daily precipitation data from 109 meteorological observation stations in Shanxi province from 1980 to 2020,ten extreme precipitation indices were selected.The spatial and temporal distribution of an extreme precipitation in Shanxi province was investigated,by using the methods of the climatic tendency rate,correlation analysis,factor analysis and R/S prediction methods.The results show that:(1)From a temporal perspective,the intensity and extremes of extreme precipitation in Shanxi province have significantly increased.The number of consecutive dry days and consecutive wet days has decreased,while other indices have shown varying degrees of increasing,with the annual total precipitation showing the most significant increase.From the perspective of spatial scale,the annual total precipitation,precipitation intensity,precipitation frequency,and extreme values were all not distributed homogeneously,gradually increasing from northwest to southeast.Additionally,the extreme events in the northern and central regions show the most significant increase in extreme events.The number of consecutive dry days in the northern region is increasing,while there is significant spatial difference in the climate trend rate of consecutive wet days.The central region has shown a significant increase,while the trend in the northern and southern regions is mainly decreasing.(2)Extreme precipitation indices(except for the number of consecutive dry days)show a strong correlation with the annual total precipitation.The contribution of heavy precipitation and very heavy precipitation to the annual total precipitation shows an increasing trend.The cumulative contribution rate of the variance of the three common factors reached 87%,reflecting the significant influence of extreme precipitation intensity and precipitation index on extreme precipitation.The R/S analysis method shows a weak decreasing trend in the future for the annual total precipitation,rainy days,heavy rain days,and maximum 5-day precipitation,while the number of drought days continues to decrease and the consecutive wet days show a weak increasing trend.Overall,extreme precipitation in Shanxi province has shown an increasing trend in recent years with significant spatial differences.