Atmospheric chemistry in volcanic plumes

摘要: Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to role chemical cycles involving halogen species and heterogeneous reactions on aerosol particles previously been unexplored for this type volcanic plumes. Key features these measurements can be reproduced by numerical models such as one employed in study. The model shows sustained high levels reactive bromine plume, leading extensive ozone destruction, that, depending plume dispersal, maintained several days. concentrations sulfur dioxide reduces lifetime OH radical drastically, so it is virtually absent plume. This would imply an increased methane plumes, unless chlorine chemistry strong enough offset lack chemistry. A further effect addition destruction studies presented here, oxidation mercury. relates mercury has coemitted with from volcano but also background rapid implies a drastically reduced contribution might less than thought. However, implications, especially health environmental effects due deposition, substantial warrant studies, test hypothesis.