Applicaton of the extreme drought events in Xinjiang from the standard precipitation index
With monthly precipitation data from 49 meteorological stations in Xinjiang during 1961-2008,the corresponding SPI were calculated and then the climatic characteristics of extreme drought in Xinjiang were studied by using the RPCA modal analysis methods.The results show that in general,from 1961 to 2008,the ratio of extreme drought area in Xinjiang showed a decreasing trend.Before 1980 s,the extreme drought area was larger,almost above 20％.After 1980 s,it was about 10％; From 2000,the extreme drought area showed an increasing trend; M-K test showed that there was an abrupt change of the extreme drought in mid-1970 s.The northern part of Xinjiang was the region with the highest occurring frequency of extreme drought,and the extreme drought of Xinjiang could be separated into three regions by using the principal component rotating method:North of Xinjiang (the representative station is Shihezi),South of Xinjiang (the representative station is Keping) and East of Xinjiang (the representative station is Qijiaojing).According to the definition of extreme drought,the extreme drought years in Xinjiang during 1961-2008 were 1962-1965,1967-1968,1973-1979,1982,1984-1985,1991,1995 and 1997,and the strong extreme drought years were 1962,1974-1975 and 1997,with the extreme drought stations in the corresponding years far exceeding the average numbers of that period.
standard precipitation indexextreme droughtextreme drought area ratioextreme drought frequencyXinjiang
NETL
NSTL
万方数据
维普
