Investigating spatiotemporal snow cover variability via cloud-free MODIS snow cover product in Central Alborz Region

摘要: Abstract Snow is a major source of streamflow in Central Alborz Mountains northern Iran. Hence, understanding the spatial distribution and temporal variation snow crucial for proper management limited water resources this region. Since in-situ measurements area are not sufficient, we used Moderate Resolution Imaging Spectroradiometer (MODIS) cover products, which their capabilities providing spatially distributed accurate mapping have been well demonstrated. In analysis, considered all available MODIS acquisitions from both Aqua Terra satellites total 4873 daily tiles MOD10A1 MYD10A1 with 500-meters resolution (version 5), collected during winter seasons between years 2002 2015. The problem cloud coverage, serious constraints to area, addressed by developing sequential removal algorithm, applies different methods subsequently considering performance each month. results indicate that proposed algorithm able reduce 94% coverage preserve accuracy cloud-removed 93%. addition, clear decreasing trend observed For example, analysis (at 10% significance level) shows 61% areas 2000 2300 m elevation levels experienced reduction duration annual cover. Moreover, general season also evident over entire study area. spite short (13 years) research, outcomes severe recent years.