Snow is a very important factor in the hydrological cycle, since it retains a large part of water. Rapid snowmelt can cause flooding, while on the other hand, the lack of snow in some river basins can lead to summer draught. Therefore the comparison of two snowmelt models HEC-HMS (version 3.5) and SRM (version 1.12) for the Sava-Kranjska Gora basin has been made in this thesis. In the first part of the thesis we described energy budget of snow cover, physical processes involved in snow accumulation, metamorphosis and melt, and fundamental equations that describe these processes. The formation of snow is affected by the conditions in clouds; the distribution and amount of snow depends on factors such as wind, vegetation, air temperature, solar radiation, precipitation and heat conduction from the ground. Snowmelt, density, temperature and snow albedo have to be considered by computing. For the determination of the melted water knowledge of snow water equivalent (SWE) is required. SWE gives us the amount of water that would be obtained if the sample of snow is fully melted. Basic approaches for streamflow forecasting and computing snowmelt are: extensive data energy budget method and temperature index method which is simpler to use, but less accurate. Both models, HEC-HMS and SRM, calculate snowmelt with the temperature index approach. Further, the physical geographical and hydrological characteristics of the drainage basin of the Sava-Kranjska Gora and preparation of the necessary input data for both models are presented. The models were calibrated based on
measured precipitation events and runoff of two months. The thesis also contains the results of the calibration, the sensitivity analysis and the comparison of models.
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