2003-2012年四川省积雪时空动态变化与气候响应研究

积雪是地球表层覆盖的重要组成部分，以高反射率、低导热率对地球能量和辐射平衡产生重要影响。利用遥感和GIS等方法能够获得大范围的雪盖信息，了解其时空分布特征及变化规律，可以对有关部门提供防灾减灾的信息。采用2003-2012年MOD10A2数据和四川省48个气象观测站的温度、降水量、湿度、气压和日照时数等数据，分析了10a四川省积雪覆盖的时空变化特征及其与气候之间的关系。结果表明：四川省积雪覆盖的空间分布呈现出西部高原多积雪，成都平原覆盖少，东部盆地几乎无积雪覆盖的阶梯式结构；2003-2012年近10a来，积雪覆盖面积年际变化呈现出小幅度波动，峰值出现于2008年，从总体趋势来看，积雪覆盖面积呈现出微弱的下降趋势；通过分析10a来积雪覆盖率与气温、降水、湿度、气压、日照时数的相关性可知，积雪覆盖率的变化特征与气温和降水的关系最为密切，与湿度的相关性一般，与气压和日照时数的关系较弱。研究表明，四川省积雪变化受气温的影响大于降水的影响，气温越高，降水量越多，积雪面积越少，反之，积雪面积越大。

Study of spatiotemporal dynamics and climate response of snow cover in Sichuan Province from 2003 to 2012

Snow is an important part of the Earth's surface with high reflectivity and low thermal conductivity which can affect earth's energy and radiation balance.By using the methods of remote sensing and GIS,a wide range of snow cover information is obtained.The spatial distribution characteristics and variation of snow cover are revealed,which can be provided to relevant departments of disaster prevention and mitigation.Based on the MOD10A2 data and records from 48 meteorological observatories of temperature,precipitation,humidity,air pressure and sunshine time from 2003 to 2012 in Sichuan Province,the spatial and temporal variation characteristics of snow cover and their relation with the climate factors in the province in recent 10 years were analyzed.The analysis results show that the spatial distribution of snow cover in the province is high snow cover rate in the western plateau,less snow cover in the Chengdu plain and even no snow cover in eastern basin.From 2003 through 2012,snow cover area had showed a small fluctuation with a peak in 2008.As a whole,snow cover area has a little shrinking tendency;it is found that snow cover rate has significant relation with temperature and precipitation and insignificant relation with air pressure and sunshine time.It is demonstrated that snow cover change in the province is mainly controlled by temperature rather than by precipitation;the higher the temperature and the more the precipitation,the less the snow cover area.