Depletion of H2O2 in a Greenland ice core: implications for oxidation of volcanic SO2

• Published in: Nature (London) 1990-07, Vol.346 (6279), p.45-48
• Main Authors: Laj, Paolo, Drummey, Scott M., Spencer, Mary Jo, Palais, Julie M., Sigurdsson, Haraldur
• Format: Article
• Language: English
• Subjects: Acids; Atmosphere; Chromatography; Climate change; Depletion; Earth, ocean, space; Exact sciences and technology; External geophysics; Fallout; Humanities and Social Sciences; Hydrogen peroxide; Ice; Ice cores; letter; Meteorology; multidisciplinary; Oxidation; Precipitation; Science; Science (multidisciplinary); Seasonal variations; Stratosphere; Sulfates; Sulfur; Sulfur compounds; Sulfur dioxide; Sulfuric acid; Troposphere; Volcanic eruptions
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/346045a0

MAJOR volcanic eruptions inject large quantities of sulphur compounds into the atmosphere 1 . A principal component is sulphur dioxide; subsequent oxidation of SO 2 in the atmosphere to sulphuric acid aerosol may lead to climate perturbations 2 . Here we present evidence to suggest that SO 2 oxidation may occur at high latitudes by reaction with H 2 O 2 . Variations in sulphate and H 2 O 2 concentrations in four sections of a Greenland ice core (corresponding to four volcanic events) show that high sulphate concentrations, from volcanic fallout, are accompanied by depletion of H 2 O 2 . This suggests that some of the volcanic sulphur was still in the form of SO 2 when it reached Greenland, and was then oxidized by H 2 O 2 in Greenland precipitation. As SO 2 oxidation in the stratosphere is very slow, volcanic events that inject SO 2 into the stratosphere could produce large depletions of distant H 2 O 2 reservoirs when the material is later reinjected into the troposphere.