气候变化背景下桂东地区旱涝变化特征分析

Analysis of drought and flood characteristics of eastern Guangxi under the background of climate change

应用降水Z指数和沙道夫干湿指数Si,对桂东地区9个站点1965-2013年近49a的年平均气温和降水资料进行分析,得出结论:近49a来,桂东地区干旱程度有明显的加重趋势,且南部比北部的大旱年数多4a左右;存在18a、13a、6a、4a、2a尺度的震荡周期,从较大尺度的振荡周期来看,从2012年开始,桂东地区进入了一个新的洪涝期;在桂东地区旱涝特征研究上,Si指数比Z指数方法更具有优越性,研究结果具有一定的指导意义和实际应用价值。

Based on the Z index of precipitation and dry-wet index Si, the annual mean temperature and precipitation data of 9 stations from 1965 to 2013 in eastern Guangxi were analyzed. The conclusion is that in the past 49 years, the degree of drought has increased significantly in eastern Guangxi and the south is 4 a more than the north in drought years; there are oscillation periods of 18 a, 13 a, 6 a, 4 a, and 2 A scales, additionally, from the large-scale oscillation period, the eastern Guangxi has entered a new flood period from 2012. In the study of drought and flood characteristics in eastern Guangxi, the Si index is more advantageous than the Z index and our research results can provide a guide for application.