Abstract: In this paper, the spatial distribution and time evolution of wind speed over northwest China in winter in recent 37 years from 1970 to 2006 were analyzed base on EOF analysis, sharp climate change test and correlation analysis. The spatial distribution pattern and temporal variation trend of surface sensible heat in spring and summer as well as the correlation between wind speed in winter and surface sensible heat in next spring and summer in the arid regions of northwest China during the period of 1982-2006 were investigated and examined. Results show that the average wind speed over northwest China in winter in recent 25 years was significantly decreased, and wind speed was universally high in the 1970s, decreased in the 1980s, universally low in the 1990s, and increased slowly during the period from 2000 to 2006. The interdecadal variation and sharp change of wind speed accorded basically with the change of surface sensible heat in next spring and summer. There was a good positive correlation between wind speed in winter and surface sensible heat in next spring and summer, and the significant correlation occurred in the Tianshan Mountains, Qiemo, Hashun Gobi Desert, Kumtag Desert and west Inner Mongolia.

Key words: surface wind speed, surface sensible heat, EOF analysis, correlation analysis, sharp climate change, northwest China