珠江流域(云南境内)1964—2013年极端气候事件的时空变化特征分析

Analysis on Spatial and Temporal Variation Characteristics of Extreme Climate Events in the Pearl River Basin within Yunnan Province from 1964 to 2013

根据1964—2013年珠江流域(云南境内)25个气象站点逐日最高、最低气温和降水数据,采用线性趋势和Mann-Kendall秩次检验方法,分析了珠江流域(云南境内)极端气候指数的时空变化特征。结果表明:①近50a珠江流域(云南境内)霜日日数FD、强降水日数R10、普通日降水强度SDII和最多连续雨日天数CWD呈极显著或显著减小趋势,夏日日数SU、极端最低气温TNn和最多连续无雨日天数CDD呈极显著或显著上升趋势,极端最高气温TXx呈弱上升趋势,且各极端气温指数发生显著变化的年份基本上在2000年以后,各极端降水指数发生显著变化的年份均是在2009年以后;②SU、TXx和TNn整体上呈现出北低南高的分布特征,FD则呈现出相反的分布特征;SDII、R10和CWD整体上呈现出东高西低的分布特征,CDD则呈现出相反的分布特征;③珠江流域(云南境内)干暖化趋势明显加剧,其中西部变暖趋势明显,东部变干趋势明显。

Based on the date of daily maximum,minimum and precipitation data from 25 meteorological stations in the Pearl River (within Yunnan province) from 1964 to 2013,this paper analyzes the temporal and spatial variation characteristics of extreme climate events in the Pearl River (within Yunnan province) by the linear trend and Mann-Kendall rank test.The results show that:①For Pearl River Basin within Yunnan Province in recent 50 years,FD (frost days),R10 (heavy rainfall days),SDII(simple daily intensity index) and CWD(consecutive wet days) showed a extremely significant or significant decreasing trend,SU (summer days),TNn (extreme minimum temperature) and CDD(consecutive dry days)exhibited a extremely significant or significant increasing trend,TXx(extreme maximum temperature) showed a weak increasing trend,as well as the extreme temperature index was changed significantly after 2000,and the extreme precipitation index was changed significantly after 2009.②In overall,SU,TX x and TN n showed a trend of higher in south,lower in north,but the distribution trend of FD is opposite to that;SDII,R 10 and CWD showe trend of higher in east,lower in west,but the distribution trend of CDD is opposite to that.③The drying and warming trend had obviously increased in the Pearl River Basin (within Yunnan province),in which the warming trend had obviously increased in the west,and the drying trend had obviously increased in the east.