秦岭主峰太白山积雪时空变化规律及驱动机制分析

Remote sensing monitoring change of snow cover and its influencing factors in Taibai Mountain

利用2000—2017年LandsatTM数据,基于SNOMAP算法提取秦岭主峰太白山积雪面积,同时结合研究区地形数据及10个气象站点的气象观测数据,分析太白山积雪变化特征及其与地形、气候因素的关系。结果表明:(1)2000-2017年冷季太白山积雪面积在波动中减少。积雪面积消减率为24.15%;(2)影响太白山积雪变化的地形因素呈现出相同的规律特点,伴随海拔的升高,积雪覆盖率在2500m以上大幅减少,同时随坡度增大,积雪覆盖率总体随坡度变化呈V型分布;(3)气象因素中太白山积雪面积减少受冷季平均气温升高影响较大,通径分析结果显示太白山积雪面积变化受地形因素及气候因素等多方面因素影响。

At the background of global warming trend,the snow cover has been a climatic factor that affects the global heat balance.The snow cover in Taibai Mountain is a key area for studying climate change in northern China.By strengthening monitoring the change of snow cover,we can not only understand the characteristics and trends of glacier and snow change,but also possibly predict future changes of snow.By using remote sensing images of Landsat 5 and Landsat 8,and SNOMAP Snow Index,the snow area was extracted.At the same time,DEM data and surrounding temperature and precipitation data from 2000 to 2017 in Taibai Mountain were used to explore the relationship between the change of snow cover of Taibai Mountain and the terrain and climate in this area.The results show as follows:(1)The area of snow cover continued to shrink in Taibai Mountain.From 2000 to 2017,the snow cover reduced by 24.15%.(2)The topographical factors of snow cover showed the same regular characteristics,and the change rate of snow cover generally showed a V-shape distribution with changes in altitude and slope.(3)The influence of the average temperature and precipitation on the snow cover in winter were different.The increase of the average temperature was the main factor affecting the snow cover change.