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Analytical and Experimental Study of Radiation-Recrystallized Near-Surface Facets in Snow: Author: Morstad, Blake Walden; Date: 2004-08-15; Program: Mechanical Engineering; Abstract: A study on the formation of radiation recrystallized near-surface facets in snow was performed experimentally in an environmental chamber. This recrystallization occurs when surface snow metamorphoses into faceted crystals that result from absorbed solar radiation coupled with cooling effects from longwave and turbulent fluxes. The environmental chamber utilized a metal-halide lamp to mimic solar radiation, which penetrates the snow adding thermal energy at depth. In addition, the ceiling was cooled to simulate a cold sky, thus inducing a net longwave radiation loss at the snow surfacE. Turbul...; Download File | View full details

Intergranular Water and Permeability of the Lake Vostok Accretion Ice, Eastern Antarctica: Author: Jepsen, Steven Michael; Date: 2005-12-15; Program: Engineering; Abstract: The relative importance of nonhydrostatic stress and lattice-rejected impurities on the phase equilibrium of intergranular liquid water in the Vostok accretion ice, Eastern Antarctica, was examined in this study. In addition, experiments were conducted to examine the influence of intergranular water in ice on the permeability of a Light Non-Aqueous Phase Liquid (LNAPL) hydrocarbon. Sub-grain scale stresses in the Vostok accretion ice were simulated with anisotropic elastic and elastocreep finite element (FE) models and compared to X-ray dislocation topographs. The phase equilibrium conditions ...; Download File | View full details

Slope scale modeling of snow surface temperature in topographically complex terrain: Author: Staples, James Mark; Date: 2008-12-15; Program: Civil Engineering; Abstract: In mountainous terrain, landscape can influences the thermal state of snow. Snow temperature and mass flux have been calculated using an energy balance model, Radtherm/RT, to account for the effects of topography and meteorological conditions. For a specific location, a terrain model is defined and contains a connected assemblage of elements or facets. Each element has a specified terrain type with assigned thermal properties. Meteorological data are applied, and a one dimensional energy balance is calculated for each element. This energy balance includes conduction, convection, radiation, and...; Download File | View full details