使用湖南省88个国家基准气象站1961~2015年的逐日降水量数据,分析了湖南地区冬夏季代表降水不同方面的PRCPTOT、SDII、R95T、R10、R5d、CDD、CWD指数的时空特征,并讨论了不同指数之间的相关性.结果表明:无论在冬季还是在夏季,PRCPTOT和SDII的空间分布较为一致.PRCPTOT和SDII在冬季增加较夏季显著,且SDII较PRCPTOT增加显著.极端降水的变化特征在冬夏有较大的差异,冬季R5 d在湘北的增加趋势较夏季显著,但夏季R95T在湘中的增加趋势较冬季显著.连续性降水指数CDD和CWD在冬季的变化趋势较夏季显著,冬季CDD在湘中地区近年来有增加趋势,而CWD在大部分湖南地区都呈下降趋势,但R5d在增加,即连续性降水的时间在减少,但连续的降水量在增加;在夏季也有同样的特征.各个指数之间的时间变化一致性较空间变化一致性强.除连续性指数CDD和CWD外,无论冬夏,其余指数在时间和空间变化上,均有较高的相关性,相关系数均通过95%的显著性检验.%Based on the daily precipitation data of 88 national weather stations in Hunan province during 1961~2015, weanalyzed the spatial and temporal distribution characteristics of several precipitation indexes [total precipitation (PRCPTOT),precipitation intensity(SDII ), fration of total from heavy events (R95T), heavy precipitation days (R10), maximum precipitationfor 5 consecutive days (R5d), maximum consecutive dry days (CDD), and consecutive wet days (CWD)〗in winter andsummer in Hunan province, and explored the correlations among these indexes.The results indicated that the spatial distributionof PRCPTOT and SDII was relatively consistent no matter in winter or in summer.The increasing trend of both PRCPTOT and SDIIin winter was more significant than that in summer, and SDII increased more significantly than PRCPTOT.In northern Hunanprovince, R5d in winter had a more significant increasing trend than that in summer.However, in central Hunan province, R95Tin summer had a more significant increasing trend than that in winter.The change trend of CDD and CWD in winter was more singificantthan that in summer.CDD in winter in central Hunan province revealed a rising trend in recent years, while CWD in mostregions of Hunan showed a declining trend, and R5d was increasing in both winter and summer.The uniformity in temporal variationsamong various indexes was stronger than that in spatial variations.Except for CDD and CWD, there were significant correlations(P<0.05) in spatial and temporal variations in both winter and summer among the other indexes .
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