Study On The Spatiotemporal-Characteristics Of Snow In Xilin Gol Area

Xilin Gol area is an important ecological barrier in the north of China,is also located in one of the three largest snow cover areas in China.The landform of research area is wide and the snow distribution is different.The spatiotemporal and characteristics of snowfall and snow depth and snow cover days were analyzed based on the data of 1971?2015 from 15 meteorological stations of Xilin Gol.Correlation between snow cover days and meteorological factors were revealed.The future trend of the snow cover days were preliminary predicted.the main results were as follows:1.Snowfall,snow depth and snow cover days were intense fluctuation with time in Xilingol,and the fluctuation law of each site is basically the same,there were no significant changes in trends.In one year,characteristics of snowfall was a"bimodal" fluctuation.snowfall was the largest in November and minimal in January.characteristics of snow depth and snow cover days were a "single peak"fluctuation:the maximum values of snow depth and snow cover days were in February and in January respectively,and the minimum value appeared in October.2.The spatial distribution of snowfall,snow depth and snow cover days were significantly different with much fewer in the south and east than in the north and west.The high value of surrounding area was mainly distributed in Wulagai,Xiwuqi,Zhengxiangbaiqi and Taibusiqi,less snow area mainly occurred in the western region.The maximum and minimtum of snowfall and sonw depth was nearly four times,and the snow cover days was more than two times.The study area was divided into 4 types according to zoning principle:Uniformly high area,Median area,one low-two high area,Uniformly less area.The spatial distribution of three snow index was further classified by EOF based on the above analysis.3.Snow cycle of near 45 years of xilin Gol was analysed by wavelet analysis.there were quasi-periods of 7a?11a and 18a in the snowfall,there were quasi-periods of 7 years,11 years and 22 years in the snow cover days,there were quasi-periods of 5a and 11a in the snow depth.The main cycle of snowfall and snow cover days was 7 years,and the main cycle of snow depth is 5 years.The results showed that the snowfall and snow depth had no mutation occurred,and the snow cover days occurred at 1996 and changed from much to less.4.The snow cover days in Xilingol affected by a variety of meteorological factors,the analysis of correlation showed that there is a high correlation between snowfall,snow depth,air temperature and humidity and snow cover days.The snow cover days had a gradually decreasing trend in the next ten years by using BP neural network forecast model.