Abstract: The Mu Us Sandy Land is located in the transitional zone of multi-level ecological geographic landscape types. Study on the extreme air temperature change in the ecological fragile region is helpful to reveal the complex relationship between the global air temperature change and the local temperature response, and provide a reference for the local environmental sustainable development and the prevention of meteorological disasters. The methods of linear trend analysis, accumulative anomaly, Mann-Kendall examination, factor analysis and R/S analysis are employed to analyze the temporal variability of extreme air temperature change in Mu Us Sandy Land during 1960-2013. Results show that: (1)The extreme minimum air temperature, extreme maximum air temperature, summer days, tropical nights, warm nights and warm days increased at different rates, and ice days, frost days, cold nights, cold days decreased at different rates. (2)In addition to the extreme maximum air temperature and extreme minimum air temperature, the remaining eight extreme air temperature indices took place abrupt change in 1990s. (3)Cold index decrease was the main characteristics of the extreme air temperature change, and the cold indices were positively correlated with each other as well as warm indices. (4)The extreme air temperature exhibited spatial distribution difference, cold index significantly reduced in northeast (Yulin and Etuoke Banner), and warm indices significantly increased in south-west(Hengshan and Yanchi). (5)The ENSO events caused extreme maximum air temperature decrease and extreme minimum air temperatures increase. (6)The Hurst index of 10 extreme air temperature indices were all greater than 0.5, which indicated that cold indices would decrease and warm indices would increase in the future in Mu Us Sandy Land.

Key words: Mu Us Sandy Land, extreme air temperature, mutation analysis, factor analysis, R/S analysis