三峡库区香溪河流域近20年气候趋势分析

根据三峡库区香溪河流域兴山气象站1990～2009年20年的气象资料，利用Mann—Kendall检验法对该地区的降水量、气温、湿度、风速、日照时数（太阳辐射）等变化进行趋势分析．结果表明：近20年，香溪河流域降雨量无显著上升趋势，增加速率约为12mm／10a，但具有明显的年际变化；春夏季降雨量呈上升趋势，秋季和冬季降雨量呈下降趋势；在全球变暖的气候背景下，香溪河流域气温逐渐升高，平均气温增加速率为0．3℃／10a，平均最低气温增加速率为0．19℃／10a，最高气温显著上升，上升速率为0．4℃／10a；风速先减小后呈上升趋势，1990～2002年风速减小，减小速率为0．1m／s／10a，自2003年以来，风速显著上升，增加速率为0．2m／s／10a；湿度呈减少趋势，月目照时数与月蒸发量呈正相关性，但总体增长趋势则表现为年日照时数增加，年蒸发量减少．

Climate Change Trend Analysis of Xiangxi River Basin of Three Gorges Reservoir Region in Recent 20 Years

Based on meteorological data from Xingshan weather station from 1990 to 2009, which is located at Xiangxi River Basin of Three Gorges Reservoir region, the change tendency of precipitation, air temperature, humidity, wind speed and sunshine duration （solar radiation） in this region was examined using method of Mann-Kendall test. The results show that： Over the past 20 years, the increase of precipitation was not significant （12 mm/10a） but with apparent inter-annual fluctuations; precipitation in spring and summer was increasing, while fall and winter was decreasing; in the context of global warming climate, the air temperature in this region has increased gradually, the average temperature increase is 0.3℃/10 a; the mean minimum in- crease is 0.19℃/10 a and the maximum increase is 0.4℃/10 a （significant）; wind speed decreased firstly and then increased; during 1990-2002 wind speed decreased （0.1 m/s/10 a）; then since 2003 increased significantly （0.2 m/s/10 a） ; humidity was decreasing and monthly evaporation capacity was positively correlated to sunshine duration, while the overall annual tendency presented a negatively correlation.