Snowpack energy exchange: Topographic and forest effects

TitleSnowpack energy exchange: Topographic and forest effects
Publication TypeBook Chapter
Year of Publication2008
AuthorsDeWalle D., Rango A.
Book TitlePrinciples of Snow Hydrology
ChapterChapter 7
PublisherCambridge University Press
CityCambridge, NY
ARIS Log Number182700
Keywordseffects, energy, exchange, forest, modeling, snowpack, topographic

Recent innovations in computing techniques and the need for modeling snowpack energy exchange processes for large diverse basins have lead to consideration of topographic and forest effects. Both topography and forests can have a major impact on snowpack radiation energy exchange. Effects on convective exchange are less well known. Methods for adjusting the basic theory of snowpack energy exchange for the effects of topography and forests are considered in this chapter. Latent heat and sensible heat convection were much lower in the forest than in the open due to reduced wind speeds. Net radiation was the dominant snowpack energy budget component at both the open and forest sites. Net radiation was reduced by about 20% by the forest relative to the open, based upon regression analysis of hourly data. Because of overall differences in net radiation and total energy supply to the snowpack, daily snowmelt rates in the forest were reduced by 15-60% compared to melt at the open site. Results of this study illustrate how forest cover can reduce the snowpack energy supply and how more humid conditions can increase the importance of latent heat convection as a source of melt energy.