A record of carbonyl sulfide from Antarctic ice over the last 1000 years

• Published in: Mineralogical Magazine
• Main Authors: Allin, SJ, Sturges, WT, Laube, J, Etheridge, DM, Rubino, M, Trudinger, CM, Curran, M, Smith, AM, Mulvaney, R
• Format: Conference Object
• Language: English
• Published: Geochemical Society 2013
• Subjects: Carbon oxysulfide; Gases; Troposphere; Stratosphere; Aerosols; Plant; Antarctic; Dronning Maud Land; Law Dome; Antarc*; DML
• Online Access: http://apo.ansto.gov.au/dspace/handle/10238/6408; https://goldschmidt.info/2013/abstracts/abstractView?id=2013004524

Carbonyl sulfide (COS) is a trace gas, present in the troposphere, and also in the stratosphere, where it contributes to the stratospheric sulfate aerosol layer. It has both natural and anthropogenic sources. Natural processes include uptake by plants, while oceans, wetlands, volcanism and biomass burning all contribute to natural COS emissions. We have measured COS in Antarctic ice cores from Dronning Maud Land, drilled in 1998, the DE08 core drilled at Law Dome in 1987, and the DSS0506 core drilled in 2006. Ice samples with COS gas ages between about 1050 AD and the early 20th centrury have been examined. A large volume ice crusher at the CSIRO Marine and Atmospheric Research laboratory was used to extract air from bubbles occluded in the ice cores. These air samples were analysed for CO2, CH4, CO and 13CO2 at CSIRO, and then for COS and several halocarbons at the University of East Anglia on a high sensitivity gas chromatograph/tri-sector mass spectrometer system. Initial results indicate that good sample integrity can be achieved. Measurements from the DML samples indicate low and uniform abundances across the last few hundred years, and at concentrations significantly below those in the modernday atmosphere. Measurements in more recent ice from DE08 show the start of increasing concentrations in the early 1900s, confirming earlier evidence that the global atmospheric abundance of COS has increased as a result of industrial activity during the 20th century.