Item: Surface hoar growth from valley clouds
Title: Surface hoar growth from valley clouds
Proceedings: Proceedings of the 2006 International Snow Science Workshop, Telluride, Colorado
Authors: Sam Colbeck and Bruce Jamieson. Lyme, New Hampshire, USA Dept. of Civil Engineering, Dept. of Geology and Geophysics, University of Calgary, Calgary, Canada
Abstract: Avalanches release from buried surface hoar layers which form when stratus clouds extend across valleys on consecutive nights. Water vapor diffusion over distances of more than a meter is much too weak to account for the growth so non-diffusive movement in some form is necessary. The most likely mechanism for the formation of surface hoar is rapid deposition of vapor as the cloud thickens and moves up the snow slope. Since the time over which deposition could take place on any given night is short, successive nights are needed to produce a substantial deposit of hoar.
Keywords: surface hoar, stratus cloud, snowpack stratigraphy, snow slab avalanches
Digital Abstract Not Available