Estimation of Snowmelt Runoff in Northern Khorasan Basin by using winSRM Model(Case Study: Darband Samalghan Basin)

Snow is a form of precipitation that plays a key role in runoff generation at mountain climate watersheds. Because of a time delay between the snowfall and its melting process, the generated runoff has a differnet behavior than other form runoff generations. DarbandSamalghan is one of the important mountain climate watersheds in North Khorsan province that its snowmelt runoff has a significant influence in the watershed streamflow. In this study a snowmelt runoff model (WinSRM) applied for runoff simulation during the two water year 2010-11 as calibration and 2011-12 for validation by using the MODIS satellite data. The model can estimate the snowmelt runoff using metorogical, hydrological and physical characterstics of the watershed as well as provinding the output simulations in diffrenet form of charts and values. The results showed a good agreement between the simulated and observed streamflow data. The determination coefficient and difference volume were 0.88 and -3.3 % for the first year, and 0.72 and 0.3 for the next year of simulation respectively. Finally, results of this study indicated the high capability of the WinSRM model and this model can be applied for the other watersheds in the region.