Analysis on the trend of drought under the support of geographic information technology—Taking Pu'er City in Yunnan Province as an example

Under the support of geographic information technology,it is combined monthly observation data of 10 county meteorological observation stations in Pu'er City in 1981—2010,and the characteristics of meteorological drought in Pu'er City is analyzed using Mann Kendall trend test,linear trend estimation,precipitation anomaly percentage etc.The results show that the precipitation show a downward trend on the whole,in spring,precipitation showed a small rise,but it showed downward trend in summer,autumn and winter,the overall reducing speed is 10.286mm/a.Precipitation in southwest shows an increasing trend and the central region showed a decreasing trend,with certain regional characteristics.The most serious drought counties in 2009 in Jingdong and Zhengyuan are in moderate drought index,meanwhile the precipitation trend showed negative value.So the degree of drought in the two counties showed the increasing trend in the future.