四川省暴雨变化特征

Characteristics of Rainstorm Variation in Sichuan Province

摘要: 为进一步研究四川地区暴雨变化特征，选取四川省32个气象站1961~2019年共59年的逐日降水量基本气象观测资料，通过一元线性回归分析、小波分析等方法，对四川省暴雨的时空变化特征进行了详细研究，结果表明：1) 四川省暴雨主要集中在6~9月，总体呈先升后降的长期变化趋势，在7月达到暴雨峰值。四川省月暴雨分布型态为东部大于西部，南部大于北部。2) 四川春、夏、秋季以及年暴雨均呈东多西少的形势，年暴雨峰值出现在雅安。3) 1961年至2019年春季暴雨长期趋势变化不显著，夏季暴雨和年暴雨呈显著增加的长期变化趋势，而秋季暴雨呈显著下降的长期变化趋势。4) 四川省春季暴雨振荡主周期分别为7a和25a，夏季暴雨和年暴雨振荡主周期均为44a。秋季暴雨振荡主周期分别为46a和8a。

Abstract: To further study the characteristics of heavy rainfall variation in Sichuan, the basic daily precipitation of 32 meteorological stations in Sichuan Province for a total of 59 years from 1961 to 2019 was selected. The spatial and temporal variation characteristics of heavy rainfall in Sichuan province were studied in detail by means of one-dimensional linear regression analysis and wavelet analysis. The results showed that: 1) The rainstorms in Sichuan Province were mainly concentrated in June-September, showing a trend of rising first and then falling, reaching the peak of rainstorms in July. The distribution of monthly rainstorms in Sichuan Province is larger in the east than in the west, and in the south than in the north. 2) Sichuan’s spring, summer, autumn and annual rainstorms are more in the east and less in the west. The peak of annual rainstorm occurs in Ya’an. 3) Spring storms show insignificant long-term trend changes from 1961 to 2019, summer storms and annual storms show a significant increasing long-term trend, while autumn storms show a significant decreasing long-term trend. 4) The main cycles of spring rainstorm oscillations in Sichuan Province are 7a and 25a, respectively, while the main cycles of summer rainstorm and annual rainstorm oscillations are both 44a. The main cycles of autumn rainstorm oscillations are 46a and 8a, respectively.