Measurements of C2‐C6 hydrocarbons during the Polar Sunrise1992 Experiment: Evidence for Cl atom and Br atom chemistry

The authors report the results of grab samples made in the Arctic winter atmosphere, which were analyzed for the presence of nonmethane hydrocarbons (C{sub 2} - C{sub 6}). The normal removal reactions for such species are due to OH radical reactions, which are expected to be strongly suppressed in winter months. The nonmethane hydrocarbons were observed to correlate well with methane during most of the winter. In April, during low ozone periods, additional depletions of acetylene were observed, which could be correlatied at least in part with Cl concentrations. Not all the variations could be accounted for due to chlorine reactions, and the authors argue that this could be the result of bromine reactions, whose presence would also correlate well with the observed ozone depletions.

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