ABSTRACT
Snow comprises only about 5% of all precipitation reaching the earth’s surface, but has a great impact on the earth’s energy balance due to its high albedo and low thermal conductivity. Most models of snowmelt runoff consist of two components: a snowmelt model, which simulates the process of snow accumulation and melting, and a transformation model, which takes the snowmelt or the rainfall as input data and yields the basin runoff as output. Melt models developed to simulate the accumulation and melt of snowpack can be broadly categorized as either temperature index also known as degree-day models or energy balance models. All the operational runoff models use one of these two approaches for modeling snowmelt. According to Rango and Martinec, most of the operational runoff models reported in the literature employ the degree-day approach. Brooks et al. also opined that, owing to complex data requirements, the temperature index is in greater use compared to the energy balance model.
