SO2 depletion in tropospheric volcanic plumes
Back to previous page
| Authors: | McGonigle, AJS; Delmelle, P; Oppenheimer, C; Tsanev, VI; Delfosse, T; Williams-Jones, G; Horton, K; Mather, TA |
| Year: | 2004 |
| Journal: | Geophysical Research Letters 31: L13201 Article Link (DOI) |
| Title: | SO2 depletion in tropospheric volcanic plumes |
| Abstract: | Ground based remote sensing techniques are used to measure volcanic SO2 fluxes in efforts to characterise volcanic activity. As these measurements are made several km from source there is the potential for in-plume chemical transformation of SO2 to sulphate aerosol (conversion rates are dependent on meteorological conditions), complicating interpretation of observed SO2 flux trends. In contrast to anthropogenic plumes, SO2 lifetimes are poorly constrained for tropospheric volcanic plumes, where the few previous loss rate estimates vary widely (from <<1 to >99% per hour). We report experiments conducted on the boundary layer plume of Masaya volcano, Nicaragua during the dry season. We found that SO2 fluxes showed negligible variation with plume age or diurnal variations in temperature, relative humidity and insolation, providing confirmation that remote SO2 flux measurements (typically of approximate to500-2000 s old plumes) are reliable proxies for source emissions for ash free tropospheric plumes not emitted into cloud or fog. |
Departmental members may update their publication list.