| Windy weather was a serious impact and destructive disaster in Xinjiang, the industry, agriculture, transportation often suffered serious damage, meanwhile wind energy is a renewable green energy. We researched the distribution characteristics and variation mechanism of windy weather, which could be helpful to tap and utilize climatic resource and improve the ecological environments.Based on the surface Meteorological observation data from 107 stations in Xinjiang from 1961 to 2009, by using climatologically statistics methods called virtue of linear trend analysis, Mann-Kendall method, Morlet wave analysis,correlation analysis and synthesis analysis, the temporal and spatial distribution of strong wind and its changes characteristics were analyzed. Furthermore variation mechanism of the gale days was discussed. Some significant results and new facts are obtained:①The annual mean number of gale days is selected as the major index to divide into four sub-regions, which are fewer gale region (where annual gale weather are less than 10 days), more gale region (where annual gale weather are between 10 days and 50 days), much more gale region (where annual gale weather are between 50 days and 100 days) and frequent region (where annual gale weather are more 100 days). In Xinjiang the frequent region of windy weather located in Shisanjianfang station (206d) of Eastern Xinjiang Region, the Alashankou station (155d) of northwestern region of Xinjiang, Dabancheng station (148d) of the valley of mid-Tianshan Mountain, Laofengkou station (144d) of western edge of Junggar Basin. The most frequent windy weather is Shisanjianfang station,which is a new fact that has not been revealed in the previous studies. The frequent region mainly lies in the gorge, river valley and mountain gap. Fewer gale region mainly located in southern edge of Junggar Basin, Tianshan Mountains, Southwest Tarim Basin.②Seasonally, the frequent period of gale days is in spring and summer, least in autumn. As for monthly distribution, the frequent gale mainly occurs from April to July, the most in May and June, least in January.③The annual mean gale days obviously decreased at the rate of -4.30 d/10a in Xinjiang recent 49a, Norther Xinjiang Region at the rate of -5.50 d/10a, Southern Xinjiang Region at rate of -2.71d/10a, Eastern Xinjiang Region at rate of -5.16 d/10a.④Considering decadal variation, the gale days were the most in 1960s, more in 1970s, less in 1990s and the least during 2001-2009.⑤daily variation of wind weather shown markedly single peak, it occur mainly during 18-22h,the most frequency in 20h,the duration of mostly windy weather is less than 1 hour; There occurred mainly west wind and northwest wind in Xinjiang, but Laofengkou station occurred mostly east wind.⑥There take place sudden change in mid-1980s, the gale days vary from more windy weather to less windy weather.⑦Morlet wave analysis showed that there have obvious oscillation period of 17-18 a, meanwhile there still exist period of 8-9a,6a.⑧Using NCEP global reanalysis data and the 74 circulation indexes, It is obviously positive correlation between the polar vortex strength(area) index of the northern hemisphere and the gale days of Xinjiang, the surface Mongolia high pressure and east wind of Laofengkou area were significantly positive correlativity.⑨311 strong wind weather process were summarized and classified four different types, furthermore the decadal change feature and monthly (seasonal) variation were analyzed.⑩Using NCEP global reanalysis data,the decade variation of circulation feature were analyzed recent 50a, the circulation feature of typical gale year(more or less) were analyzed, the tendency of polar vortex strength of the northern hemisphere and its area was reducing (weak or small), the intensity and frequency of the cold air activity were weakening in Xinjiang province too. It is primarily factor to the gale days have decreased. A further analysis indicated that windy weather depended on the special geographic environment and atmospheric circulation pattern.
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