Location: Northwest Watershed Management Research
Title: Dependence of snowmelt simulations on scaling of the forcing processes Authors
Submitted to: Trans American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: October 1, 2009
Publication Date: N/A
Technical Abstract: The spatial organization and scaling relationships of snow distribution in mountain environs is ultimately dependent on the controlling processes. These processes include interactions between weather, topography, vegetation, snow state, and seasonally-dependent radiation inputs. In large scale snow modeling it is vital to know these dependencies to obtain accurate predictions while reducing computational costs. This study examined the scaling characteristics of the forcing processes and the dependency of distributed snowmelt simulations to their scaling. A base model simulation characterized these processes with 10m resolution over a 14.0 km2 basin with an elevation range of 1474 – 2244 masl. Each of the major processes affecting snow accumulation and melt – precipitation, wind speed, solar radiation, thermal radiation, temperature, and vapor pressure – were independently degraded to 1 km resolution. Seasonal and event-specific results were analyzed. Results indicated that scale effects on melt vary by process and weather conditions. The dependence of melt simulations on the scaling of solar radiation fluxes also had a seasonal component. These process-based scaling characteristics should remain static through time as they are based on physical considerations. As such, these results not only provide guidance for current modeling efforts, but are also well suited to predicting how potential climate changes will affect the heterogeneity of mountain snow distributions.