1961—2016年江西不同量级暴雨的时空分布特征

Spatio-Temporal Variations of Rainstorms with Different Magnitudesin Jiangxi Province During 1961-2016

利用江西省83个站点逐日降水资料,采用滑动平均、小波分析和Mann-Kendall检验等方法,分析了1961—2016年江西春季(3—5月)、汛期(5—7月)、秋季(9—11月)不同量级暴雨的时空分布特征。结果表明:不同量级的暴雨在不同季节的变化特征存在明显的差异,降水主要集中在汛期。暴雨量在春季和秋季变化趋势平稳,而汛期在1990年之前呈减少趋势,之后呈增加趋势;其空间分布均呈“南少北多、东多西少”特征;存在准30 a和准10 a两个变化周期。大暴雨量在春季和汛期呈“先下降、后上升”的趋势,空间分布较为平均。特大暴雨发生的概率很小,主要集中在汛期,其降水量变化趋势呈“先下降、后上升”特征,空间分布集中在赣北中部和赣中东部。

Based on the data of 83 stations in Jiangxi province,the spatio-temporal variations features of rainstorms with different intensities in spring(March to May),flood-season(May to July),autumn(September to November)was studied from 1961 to 2016 by moving average,means of wavelet analysis and Mann-Kendall mutuation.Results show that the rainstorms presented different features in different seasons,and there were also significant differences among rainstorms of different magnitudes,rainfall of all magnitudes is mainly concentrated in the flood season.Variations of rainstorms were stable in spring and autumn,but in flood season,rainstorms was decreasing before 1990 and then increasing;the spatial distribution also revealing characteristics of more in north and east but less in south and west;they also showed quasi-30-year and quasi-10-year periodic change.In the spring and the flood-season,the occurrence of heavy rainstorm displayed decreased first and then increased,more evenly distributed.The probability extraordinary rainstorm was vary small,and mainly concentrated in flood-season,they had been appearing decreased first and then increased,they mainly located in middle of north Jiangxi and eastern of central Jiangxi.