The Role of Snow Cover on Surface Trace Gas Exchanges at Toolik Lake, AK

Wednesday, 17 December 2014: 1:40 PM
Detlev Helmig1, Daniel Obrist2, Chris Moore2, Brie Van Dam1, Jacques Hueber1, Timothy Molnar1, Mark W Williams1, Louisa J Kramer3, Paul V Doskey4 and Xavier Fain5, (1)University of Colorado at Boulder, Institute of Arctic and Alpine Research, Boulder, CO, United States, (2)Desert Research Institute, Reno, NV, United States, (3)Michigan Technological University, Houghton, MI, United States, (4)Michigan Tech University, Department of Civil and Environmental Engineering, Houghton, MI, United States, (5)Univ. Grenoble Alpes / CNRS, Laboratoire de Glaciologie et Géophysique de l’Environnement (LGGE), Grenoble, France
Snow has a profound influence on the emission and deposition of atmospheric trace gases in the arctic environment. Processes that play a role in modulating gas exchanges include biological, soil biogeochemical, snow chemical, and snow physical processes. Environmental conditions underneath the snow are relatively stable throughout the winter period. Above the snow surface, variations in temperature, radiation, and wind exert a wide range of influences on snowpack gas chemistry, gas exchanges at the snow-air interface, and chemical interactions between the interstitial snowpack air and vegetation and soil below the snowpack. This presentation will present an overview of experimental approaches for continuous, all winter-long experiments conducted at a permafrost site at the Long-Term Ecological Research (LTER) station at Toolik Lake on the north slope of the Brooks Range, Alaska. These studies include observations of carbon dioxide and the reactive gases ozone, nitrogen oxides, and gaseous elemental mercury. Parameterizations developed from these measurements are used for improving descriptions of trace gas budgets and their feedbacks on climate and associated snow cover changes in the Arctic and seasonally snow-covered midlatitude environments.