The characteristics of climate change and the impact factors analysis in the western part of Inner Mongolia

Using data of the temperature and precipitation at nine meteorological stations in the western Inner Mongolia,with the help of Linear trend and Mann-Kendall trend test method,combined with the impact factors of atmospheric circulation index and oscillation and monsoon,the variation characteristics of the temperature and precipitation in 1961-2009 in the west of Inner Mongolia were studied,the relationship between regional climate change and influence factors was discussed. Research shows that since 1961,the temperatures in the western region of Inner Mongolia showed increasing trend of 0. 42℃ /10a,the greatest contribution to climate warming was in winter; since twenty-first Century the temperatures increase was the most significant and the mutations occurred in 1990. The precipitation also showed an obvious increasing trend,and the most significant increasing trend was in winter,but showed no obvious mutation characteristics. The best correlation was between the air temperature in the western region of Inner Mongolia and the Tibetan Plateau index,at the same time with the Arctic Oscillation and the westerly circulation index. In the background of global warming,the Tibetan Plateau index,the Arctic Oscillation and westerly circulation index had important effect on the temperature. There was a good negative correlation between the precipitation and the advance and retreat of the East summer monsoon,which was one of the main factors affecting the change of the regional precipitation.