【摘要】 利用1959-2009年云南省30个测站逐日降水资料,通过计算趋势系数、相关系数等现代统计诊断方法,分析了近50年来云南省年、季、月雨日和降水的时空变化特征。结果表明,云南省多年平均雨日空间分布和降水量空间分布基本一致。降水量最大值出现在滇西南地区,滇中到滇东南地区相对较少;年雨日最大值也出现在滇西南地区,滇中地区最少。年降水量在近50年来总体变化不大,但是年总雨日出现明显的减少趋势,趋势系数为-0.475,通过了0.01显著性水平检验,回归系数为-3.19d.(10a)-1。季雨日的分析表明,云南省除了春季以外,其他三季雨日均呈大范围的负趋势,其中夏、秋季30个测站的趋势系数均为负值,四季通过0.05显著性水平检验的负趋势测站数从多到少的排列为夏季>秋季>冬季>春季。全年12个月中有9个月是负趋势测站的超过一半以上,尤以6～10月最明显,总的来说,月雨日呈减少趋势。更多还原

【Abstract】 Climatic changes and the spatial/temporal features of annual,seasonal,and monthly rain days in Yunnan Province are investigated using the observational data at 30 stations in the period of 1959-2009.The results showed that the spatial distributionof multi-year mean rainfall in Yunnan Province is nearly consistent with that of rain days,the maximum rainfall appears in the southwest part of Yunnan,and the minimum,is in the middle and southeast parts of Yunnan,and so the rain day does in the same way.The rainfall change is no obvious in resent 50 years,but the rain days appear obvious decreasing trend,the trend coefficient is-0.475,which has passed the confident level of 99.9% and regression coefficient is-3.19 d·(10 a)-1.The analysis of seasonal rain days showed that the temporal trends of seasonal rain days are all negative except for spring,and the trend coefficients at 30 stations all indicatenegative values in summerand autumn.The negative trend stations in four seasons passing the confident level of 95% are summer>autumn>winter>spring. Besides,there are 9 monthes in a year show negative trend stations which is more than half,particularly in June,August,Septemberand October,in general,the trend of rain days is negative.更多还原