Does change in the upstream snowpack properties contribute to desiccation of Lake Urmia?

Abstract

<p>Lake Urmia, the largest hypersaline lake in the Middle East has desiccated significantly during the past two decades. Zarrineh River Basin (ZRB), is the largest upstream basin of Lake Urmia and supplies about half of the lake inflows. We investigated 20-years of snowpack properties of this mountainous basin including snow cover area, albedo, depth, and snow water equivalent using MODIS satellite data. We found that maximum and median snow cover area, albedo, the extent and duration of deep snow have been decreased since 2010, particularly at high altitudes. Furthermore, we observed a shift in the timing of snow accumulation and depletion since 2010. These variations have led to slightly decreased inflows to the Bukan reservoir that is the main regulator of Lake Urmia inflows. However, even in those years that the share of snowmelt runoff was high, reservoir releases have not led to more water supply to Lake Urmia due to irrigation consumption. Finally, we indicated that inflows to the Bukan Reservoir and Lake Urmia have been negatively influenced by snowpack reduction. But human decisions play a more crucial role on how to use the increased snowmelt-runoff in wet years to restore the desiccated lake through improved environmental flow allocations.  </p>