1960-2005年湖南省降水的变化

Precipitation Change in Hunan Province

利用线性回归、突变分析及小波分析方法,分析了湖南省1960-2005年86个地面台站降水量的变化。结果表明:46a来湖南省年降水量呈增加的趋势,气候倾向率为21.8mm/10a,其中春秋两季降水量呈减少趋势,夏冬两季降水量呈显著增加的趋势,11a滑动平均曲线表明,今后湖南省降水量有减少趋势;湖南省在1990年代初年降水量增多是一突变现象,主要是夏冬降水量发生突变,而春秋两季无突变现象;湖南省年降水量和四季降水量存在4个主要周期的变化。

The change of precipitation in Hunan Province since recent 46 years was analyzed by using linear regression, abrupt change analysis and wavelet analysis. The results showed that the annual precipitation increased at a climatic tendency of 21.8 mm/10a. However, the 11-year running mean curve showed that it will decrease in the future. Precipitations in spring and autumn were decreasing in most of the areas, while summer and winter precipitations both had increasing trends. There existed a wetter trend in summer and winter in Hunan Province in the last 46 years. The abrupt change occurred in summer and in winter during the early 1990s. Generally, both annual precipitation and seasonal precipitation presented four kinds of periodic change.