Abstract:

Based on data of temperature, precipitation, relative humidity, sunshine hours, and maximum snow depth during 1961-2013 from 60 meteorological stations located in Tianshan mountainous area, this paper analyzed the change of climatic factors above using time series analysis and spatial analysis method. Path analysis was used to explore the impact of temperature, precipitation, relative humidity and sunshine hours on snow depth. The results showed that the climate in Tianshan mountainous area had changed a lot significantly during 1961-2013. Its main features included the significant increase of temperature and precipitation, the local increase or decrease of relative humidity, local diming for the decrease of sunshine hours and local increase of maximum snow depth. To some degree, climate warming can reduce the assurance rate of snowfall in Tianshan mountainous area. Temperature, precipitation and sunshine hours impacted on snow depth by 9 influence paths including 3 direct influence paths and 6 indirect influence paths. Direct influence paths of 3 were from temperature, precipitation and sunshine hours to snow depth directly, respectively. And 6 indirect influence paths were from temperature to precipitation to snow depth, from temperature to sunshine hours to snow depth, from precipitation to temperature to snow depth, from precipitation to sunshine hours to snow depth, from sunshine hours to temperature to snow depth and from sunshine hours to precipitation to snow depth, respectively. It was showed that the overall effect of temperature on snow was far greater than the influence of precipitation and sunshine hours.

Key words: climate change, snow cover, Tianshan mountainous area, muti-paths impact