A Study of Abrupt Climate Change in Xinjiang Region during 1961—2004

According to physical conditions and regional environmental characteristics,the Uygur Autonomous Region of Xinjiang is divided into Northern Xinjiang,Tianshan Mountains and Southern Xinjiang.Based on the data of daily mean maximum temperature,mean minimum temperature and daily precipitation from 1961 to 2004 observed at 54 meteorological stations in the Xinjiang Region,some abrupt changes of temperature and precipitation have been detected in the three areas by using Mann-Kendall test method.The calculation results are tested by moving %t%-test technique and Yamamoto method.The research results indicate that the annual mean maximum temperature,annual mean minimum temperature and annual precipitation vary with a positive trend,but the annual mean diurnal temperature range varies with a negative trend at a significant level of 0.001 in Northern Xinjiang,Tianshan Mountains and Southern Xinjiang from 1961 to 2004.In the Northern Xinjiang,the annual mean minimum temperature and annual precipitation had abrupt changes from cool to warm and from less to more in 1988 and 1984,respectively.In the Tianshan Mountains,the annual mean minimum temperature and annual precipitation changed abruptly in 1985 and 2000.In the Southern Xinjiang,the annual mean maximum temperature,annual mean minimum temperature and annual precipitation changed abruptly in 1993,1991 and 1981,respectively.The annual mean daily temperature rang in the Northern Xinjiang,Tianshan Mountains and the Southern Xinjiang changed abruptly in 1979,1983 and 1981,respectively.The climate has become warm and wet all in the Northern Xinjiang,Tianshan Mountains and the Southern Xinjiang since the later 1980s.