In this paper we assess the snow cover and its dynamics for the western riverbasins of the Indus River system and their subbasins located in Afghanistan,China, India and Pakistan for the period 2001-2012. First, we validate theModerate Resolution Imaging Spectroradiometer (MODIS) daily snow products fromTerra and Aqua against the Landsat Thematic Mapper/Enhanced Thematic Mapperplus data set, and then improve them for clouds by applying a validated nonspectral cloud removal technique. The improved snow product has been analysedon a seasonal and annual basis against different topographic parameters(aspect, elevation and slope). Our results show a decreasing tendency for theannual average snow cover for the westerlies influenced basins (upper Indusbasin, Astore, Hunza, Shigar and Shyok) and an increasing tendency for themonsoon influenced basins (Jhelum, Kabul, Swat and Gilgit). Seasonal averagesnow cover decreases during winter and autumn, and increases during spring andsummer, which is consistent with the observed cooling and warming trends duringthe respective seasons. Subbasins at relatively higher latitudes/altitudes showhigher variability than basins at lower latitudes/middle altitudes.Northeastern and northwestern aspects feature greater snow cover. The mean endof summer regional snow line altitude (SLA) zones range from 3000 to 5000 m aslfor all basins. Our analysis provides an indication of a descending end ofsummer regional SLA zone for most of the studied basins, which is significantfor the Shyok and Kabul basins, thus indicating a change in their waterresources. Such results are consistent with the observed hydroclimatic data,recently collected local perceptions and glacier mass balances for theinvestigated period within the UIB. Moreover, our analysis shows a significantcorrelation
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