内蒙古积雪面积时空变化及其对气候响应

区域尺度积雪信息的时空监测,对确定雪灾的影响范围及灾情等级划分具有重要意义。利用2002-2012年10个积雪季节的Terra Aqua/MODIS积雪产品(MOD10A2),按月最大面积合成,分析了内蒙古积雪覆盖面积的时空变化特征及气候响应。结果表明:时间上,近10年内蒙古积雪面积年内变化整体上呈现双峰和单峰的波动特点,最大积雪面积发生在12月和1月份,最小积雪面积发生在10月份。近10年内蒙古积雪面积年际变化呈现波动的特点,整体上积雪面积有减少的趋势。空间上大兴安岭西麓、呼伦贝尔高原以及乌珠穆沁盆地是积雪长时间覆盖区,锡林郭勒草原和乌兰察布草原的积雪面积变化主导着内蒙古的总体积雪面积波动,1月份之前是积雪面积增加的阶段,之后是积雪消融阶段。内蒙古的积雪面积变化与当地的气候条件变化趋势相关,气温的明显上升引起暖冬化,可能导致积雪面积的减少,说明内蒙古积雪面积的变化主要受气温的影响。

The spatial and temporal changes of snow cover in Inner Mongolia and their responses to climate

The spatial and temporal change patterns of snow cover of the Inner Mongolia were analyzed by 10 seasonal Terra Aqua/MODIS snow products(MOD10A2) collected during 2002-2010 which were composed according to maximum area rule.The results indicate that snow cover change presented fluctuation patterns of 2 peaks and 1 peak in recent 10 years.The maximum snow cover appeared in December and January and the minimum was in October.The snow cover fluctuated and had a decreasing trend.The Hulunbeier grassland and ujimqin Basin were the long-term snow coverage area.The snow cover changes of Xilin Gol and Wulanchabu Grassland were dominant in general snow cover change fluctuation.The snow in the Inner Mongolia accumulated before January and thawed after January.The changes of snow cover were consistent well with regional climate change.Temperature increasing and decrease of the precipitation were the major reason for decreases of snow cover.This indicates the climate condition has an important consequence for snow cover changes.