Author
WALTER, M - CORNELL UNIVERSITY | |
McCool, Donald | |
KING, L - WASHINGTON STATE UNIV | |
MOLNAU, M - UNIVERSITY OF IDAHO | |
CAMPBELL, G - WASHINGTON STATE UNIV |
Submitted to: Journal Hydrologic Engineering
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/1/2003 Publication Date: 6/1/2003 Citation: Walter, M.T., McCool, D.K., King, L.G., Molnau, M., Campbell, G.S. 2004. Simple snowdrift model for distributed hydrological modeling. Journal of Hydrologic Engineering. 9(4): 280-287. Interpretive Summary: Snow transport and deposition can be an important factor in the spatial distribution of spring soil moisture and runoff on cropland and other areas. Although most current hydrological models attempt to account for heterogeneities in precipitation distribution, many do not account for snowdrift effects. In this study, a simple snowdrift model was developed, coupled with an equally simple snowmelt model, incorporated into a distributed winter-time hydrological model, and tested against snow water measurements from a hillside in eastern Washington State. The snowdrift model's simulated snow distribution generally agreed with observed snow distribution across the hill. Most notable were the model's ability to correctly place a snowdrift on the lee-side of the hill and its ability to remove snow from non-drift areas of the hillside. The effects of snow redistribution and the model's ability to reproduce these were obvious when these results, and model results that ignored snowdrifts, were overlaid on observed snow water equivalents across the hill. This simple snowdrift and snowmelt model will improve the performance of hydrological models in predicting spatial distribution of snow water equivalent and hence surface runoff and lateral subsurface flow. Technical Abstract: Snow transport and deposition can be an important factor in the distribution of spring soil moisture and runoff. Although current hydrological models often attempt to account for heterogeneities in precipitation distribution they do not account for snowdrift effects. A simple snowdrift model was developed, incorporated into a distributed winter-time hydrological model, and tested against snow measurements from a hillside in eastern Washington State. Because it is impossible to field-test a snowdrift model without accounting for snowmelt and accumulation, the snowdrift model was coupled with a snowmelt model. The snowmelt model was developed to have the same level of simplicity as desired of the snowdrift model. In general, the snowmelt model introduced very few new concepts into this heavily studied realm of hydrological research and performed well against a widely accepted data set. The snowdrift model's simulated snow distribution generally agreed with observed snow distribution across a hill. Most notable were the model's ability to correctly place a snowdrift on the lee-side of the hill and its ability to remove snow from non-drift areas of the hillside. The effects of snow redistribution and the model's ability to reproduce these were obvious when these results, and model results that ignored snowdrifts, were overlaid on observed snow water equivalents across the eastern Washington hill. This simple snowdrift and snowmelt model will improve the performance of hydrological models in predicting spatial distribution of snow water equivalent and resulting surface runoff and lateral subsurface flow. |