www.atmos-chem-phys-discuss.net/7/5941/2007/ © Author(s) 2007. This work is licensed under a Creative Commons License. Snow physics as relevant to snow photochemistry 1Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS et Université Joseph Fourier, BP96, 54 rue Molière, 38402 Saint Martin d'Hères cedex, France 2Army Cold Regions Research and Engineering Lab, 72 Lyme Road, Hanover, N.H. 03755-1290, USA 3Paul Scherer Institute, Laboratory for Radiochemistry and Environmental Chemistry OFLB 106, 5232 Villigen, Switzerland 4Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany 5Institute of Environmental Physics, Bremen University, O. Hahn Allee 1, 28334 Bremen, Germany 6WSL, Swiss Federal Institute for Snow and Avalanche Research, SLF Davos,Flüelastr. 11, C7260 Davos Dorf, Switzerland 7Department of Chemistry and Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK 99775-6160, USA Abstract. Snow on the ground is a complex multiphase photochemical reactor that dramatically modifies the chemical composition of the overlying atmosphere. A quantitative description of the emissions of reactive gases by snow requires the knowledge of snow physical properties. This overview details our current understanding of how those physical properties relevant to snow photochemistry vary during snow metamorphism. Properties discussed are density, specific surface area, optical properties, thermal conductivity, permeability and gas diffusivity. Inasmuch as possible, equations to parameterize these properties as a function of climatic variables are proposed, based on field measurements, laboratory experiments and theory. The potential of remote sensing methods to obtain information on some snow physical variables such as grain size, liquid water content and snow depth are discussed. The possibilities for and difficulties of building a snow photochemistry model by adapting current snow physics models are explored. Elaborate snow physics models already exist, and including variables of particular interest to snow photochemistry such as light fluxes and specific surface area appears possible. On the other hand, understanding the nature and location of reactive molecules in snow seems to be the greatest difficulty modelers will have to face for lack of experimental data, and progress on this aspect will require the detailed study of natural snow samples. Discussion Paper (PDF, 2833 KB) Interactive Discussion (Closed, 5 Comments) Final Revised Paper (ACP) Citation: Domine, F., Albert, M., Huthwelker, T., Jacobi, H.-W., Kokhanovsky, A. A., Lehning, M., Picard, G., and Simpson, W. R.: Snow physics as relevant to snow photochemistry, Atmos. Chem. Phys. Discuss., 7, 5941-6036, 2007. Bibtex EndNote Reference Manager |
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