近50年东北地区极端降水事件时空演变特征

Spatiotemporal Evolution Characteristics of Extreme Precipitation Events in Northeastern China in Recent 50 Years

摘要: 为了进一步研究东北地区极端降水事件的时空演变特征，本文利用中国气象数据网下载的地面气候资料日值降水数据，主要选取了7个极端降水指数，通过利用线性趋势、Mann-Kendall检验、滑动t检验、小波分析和反距离加权插值的方法对1971~2020年东北地区极端降水事件的时空演变特征进行了分析。结果表明：1) 近50年东北地区降水量增加，干旱日数减少且湿润日数增多，气候逐渐变湿润；2) 7个极端降水指数中，仅有连续湿润日数CWD在1998年有突变发生；3) 7个极端降水指数显著年际震荡特征在0~9年间，均存在1~2个主周期，大多数极端降水指数的主周期在30~31年间；4) 近50年东北地区东南部强降水量、降水总量高于西北部，连续干旱日数西部多于东部，西部气候较干旱，导致极端降水事件易发于东部和南部，极端干旱事件易发于西部。

Abstract: To further study the spatial and temporal evolution characteristics of extreme precipitation events in Northeastern China, this paper used daily precipitation data of ground climate downloaded from China Meteorological Data Network and mainly selected seven extreme precipitation indices to analyze the extreme precipitation events in Northeastern China from 1971 to 2020. The spatiotemporal evolution characteristics of extreme precipitation events in Northeastern China were analyzed by using linear trend, Mann-Kendall test, sliding t test, wavelet analysis and inverse distance weighted interpolation in the last 50 years. The results showed that: 1) The precipitation in North-eastern China increased, the number of dry days decreased and the number of wet days increased in the past 50 years, and the climate has gradually become wetter; 2) Among the seven extreme precipitation indices, only the CWD of continuous wet days changed abruptly in 1998; 3) The significant interannual oscillations of the seven extreme precipitation indices were between 0 and 9 years, and there were 1~2 main cycles. The main periods of most extreme precipitation indices were 30~31 years; 4) In the last 50 years, the amount of heavy precipitation and total precipitation in the southeast of Northeastern China was higher than that in the northwest, the number of continuous drought days in the west was more than that in the east, and the climate in the west was relatively dry, which leaded to extreme precipitation events in the east and south, and extreme drought events in the west.