Snow Hydrology Model Combined with Remotely Sensed Snow Observations in the Upper Helmand Watershed, Afghanistan (Invited)
Abstract
In many regions of the world snowmelt can be an important source of water resources. However, limited data availability can make water resources planning and management difficult, particularly in developing countries. For this study, a temperature index snow model in conjunction with a hydrologic model was used to analyze the snowpack and hydrology of the Upper Helmand Watershed in Afghanistan. Limited ground data and remotely sensed precipitation data were used to develop and force the model. The snow model was calibrated using high-resolution multispectral imagery of the snow covered area (SCA). The calibrated snow model was compared to passive microwave estimates of snow water equivalent (SWE). Finally the peak snowpack, derived using the passive microwave SWE data, was used to initialize the hydrologic model prior to melt onset. The model’s ability to simulate runoff was validated using reservoir measurements at the basin outlet. This study improved our understanding of the hydrologic processes in this remote, data-scarce region. In particular, the snow extent and mass as well as the contribution of snow to runoff are quantified with enhanced confidence by using both the model simulations and remotely sensed data. The temperature index snow model accurately simulates the snow accumulation and melt process as demonstrated in the temporal and spatial comparison to the high-resolution SCA imagery. Inflows to the reservoir were reasonably simulated using the hydrologic model, though the model exhibited sensitivity to input precipitation data. The passive microwave SWE data provided reasonable estimates of snow mass and distribution in the Upper Helmand Watershed, and has potential for initializing hydrological models to add value to water supply planning and dam management.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2010
- Bibcode:
- 2010AGUFM.C13C..08V
- Keywords:
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- 0740 CRYOSPHERE / Snowmelt;
- 0758 CRYOSPHERE / Remote sensing;
- 1863 HYDROLOGY / Snow and ice;
- 1880 HYDROLOGY / Water management