摘要
鉴于近年来关于雪水当量的研究成果大部分基于物理模型进行估算,这些雪水当量数据的空间分辨率较低,且需要大量野外实测的积雪属性数据来作为输入模型的初始变量。在对中小流域雪水当量时空分布特征的估算,特别是地形因子较为复杂的山区,基于物理模型估算雪水当量以及被动微波遥感影像反演的雪水当量都不能满足需求。该文以黑河上游祁连山八宝河流域和冰沟小流域作为研究区域,利用2011年3景小流域ENVISAT-ASAR数据,获得流域积雪面积与雪水当量产品,结合DEM数据,拟合出研究区域的积雪衰减曲线。利用积雪衰减曲线,在祁连山黑河上游八宝河子流域,获取2008年逐日366天MODIS积雪面积比例产品MOD10A1数据,通过估算云下反照率的方法将逐日积雪面积比例产品进行去云处理,结合DEM数据得到像元地形因子,计算八宝河流域每个像元逐日雪水当量值,得到流域2008年雪水当量情况,分析流域内雪水当量分布规律以及流域内雪水当量年内时空变化。
Recent publications about the estimation of snow water equivalent（SWE）are mainly based on the physical model simulations and the retrievals passive microwave remote sensing data.However,the spatial resolution of the SWE from retrievals is still relatively low,and it also requires a large amount of field data to be used as the initial values in the physical snow process models.As a result,both the approaches cannot satisfy the needs in the estimation of snow water equivalent in the small watersheds,especially in mountainous area with complex terrain.In this paper,the Babaohe watershed and Binggou watershed were selected as the study areas.Firstly,a snow depletion curve（SDC）for the Binggou watershed is developed,based on the snow cover fraction（SCF）and SWE information retrieving from the three ENVISAT-ASAR images,together with the DEM data.Then,the SDC was used in the Babaohe watershed to get the daily SWE in 2008,based on the MODIS daily SCF data of MOD10A1 and DEM data.The effect of the cloud in the MOD10A1 data was eliminated through the estimation of albedo under the cloud,and the topographic factors were calculated using the DEM data to take the effect of terrain into consideration.Lastly,distribution and the temporal-spatial variation of the SWE in the Babaohe watershed of Heihe River Basin,Qilian Mountains in 2008 were discussed.
出处
《遥感信息》
CSCD
北大核心
2017年第2期121-130,共10页
Remote Sensing Information
基金
国家重大基础研究计划(2013CBA01802)
国家自然科学基金(41271356
41401414)
