Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 14 7 2010 10.5194/hess-14-1331-2010 http://www.hydrol-earth-syst-sci.net/14/1331/2010/ http://www.hydrol-earth-syst-sci.net/14/1331/2010/hess-14-1331-2010.html http://www.hydrol-earth-syst-sci.net/14/1331/2010/hess-14-1331-2010.pdf 1331 1340 2010-07-26 Measurements and modelling of snowmelt and turbulent heat fluxes over shrub tundra D. Bewley R. Essery richard.essery@ed.ac.uk J. Pomeroy C. Ménard Department of Forest Resources Management, University of British Columbia, Vancouver, Canada School of GeoSciences, University of Edinburgh, Edinburgh, UK Centre for Hydrology, University of Saskatchewan, Saskatoon, Canada Measurements of snowmelt and turbulent heat fluxes were made during the snowmelt periods of two years at two neighbouring tundra sites in the Yukon, one in a sheltered location with tall shrubs exposed above deep snow and the other in an exposed location with dwarf shrubs covered by shallow snow. The snow was about twice as deep in the valley as on the plateau at the end of each winter and melted out about 10 days later. The site with buried vegetation showed a transition from air-to-surface heat transfers to surface-to-air heat transfers as bare ground became exposed during snowmelt, but there were daytime transfers of heat from the surface to the air at the site with exposed vegetation even while snow remained on the ground. 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