Characteristics of Air Temperature in the Southern and Northern Slopes of Tianshan Mountains

Based on the observation of air temperature data in the Southern and Northern Slopes of Tianshan Mountains in recent 50 years,the change tend of annual mean temperature,different time of beginning spring and summer,the characteristics of annual maximum temperature and minimum temperature and annual temperature range are analyzed. The results showthat air temperature increased in 1997 in the southern and northern slopes of Tianshan M ountains and that the change tend of the temperature is maximum,0. 402℃ ·( 10a)- 1,in the northern slope of the Urumqi station. It suggests the beginning dates of spring and summer in the southern slope of the Kuerl station are earlier than that in the northern slope of the Urumqi Station. It enters the spring in April in the northern slope of the Urumqi Station and in M arch in the southern slope of the Kuerl station. The temperature of beginning spring in the northern slope of the Urumqi station is one degree higher than that in the southern slope of the Kuerl station. It begins the summer in June and May in the northern slope of the Urumqi station and in May in the southern slope of the Kuerl station. The temperature of beginning summer in NorthSouth slope of the Tianshan M ountains is relatively close. In addition,a statistical analysis shows that annual maximum temperatures decrease with increasing elevation and that variation of annual minimum temperatures is different in the southern and northern slopes of Tianshan M ountains. Annual temperature range decreases with increasing elevation in the southern and northern slopes of Tianshan M ountains. The inversion in the northern slope is significantly higher than that in the southern slope in January. The linear trend of air temperature difference between Xiaoquzi and Caijiahu in the northern slope is- 0. 208℃ ·( 10a)- 1. But the linear trend of air temperature difference between Baluntai and Hejing in southern slope is 0. 236℃ ·( 10a)- 1.