It has been shown that NOx is produced photochemically within the snowpack of polar regions. If emitted to the atmosphere, this processcould be a major source of NOx in remote snowcovered regions. We report here on measurements made at the German Antarctic station,Neumayer, during austral summer 1999, aimed at detecting and quantifying emissions of NOx from the surface snow. Gradients of NOxwere measured, and fluxes calculated using local meteorology measurements. On the 2 days of flux measurements, the derived fluxesshowed continual release from the snow surface, varying between similar to0 and 3x10(8) molecs/cm(2)/s. When not subject toturbulence, the variation was coincident with the uv diurnal cycle, suggesting rapid release once photochemically produced. Scaling thediurnal average of Feb. 7th (1.3x10(8) molecs/cm(2)/s) suggests an annual emission over Antarctica of the order 0.0076TgN.
AWI Organizations > Geosciences > Glaciology
AWI Organizations > Climate Sciences > Atmospheric Circulations