مدل هاي برفابي پيش بيني جريان حوزه آبريز به كمك RS و GIS

Snowmelt is an important component in riverflow forecasting of mountainous regions. In this project Dez basin upstream from the Dez reservoir is considered for developing a multi-variate riverflow forecasting model. In doing so hydrologic characteristic of the basin was studied and regional relations were obtained for several hydrological parameters including temperature, precipitation, and snow water equivalent. Dez is one the major river basins of the country and is located in southwest of Iran. It is one of the three large basins in this area, which together are said to have about 70 percent of total hydropower potentials in the country. The modeling was carried out through several approaches. RS and GIS capabilities, including areal snow cover images, GIS based regional relations, and GIS based spatial interpolations were also employed in reaching satisfactory model results. Moreover, in each approach 6 groups of models were developed to forecast flows of one to six months ahead. Later, models were compared with and without using satellite images. Results indicate an outstanding improvement when satellite snow cover maps are used. This is more significant in early spring months where snowmelt is the major source of river runoff.