DFG-Schwerpunktprogramm 1158 "Antarktisforschung"

Sea ice Atmosphere Lagrangian Transport of SALT - Part 2: Remote Sensing
Measurements of Halogen Oxides

Halogens play an important role in the polar troposphere. Here, they are responsible for the catalytic destruction of ozone in the polar boundary layer, mainly by Bromine but also by Chlorine and Iodine. These so called Ozone Depletion Events (ODE) come along with low temperatures and the reduction of gaseous Mercury in the atmosphere, the so-called Atmospheric Mercury Depletion Events (AMDE). The removal of gaseous mercury from the atmosphere leads to a mercury deposition on snow and ice surfaces in the form of particulate and reactive gaseous mercury (PM/RGM). With the melting in summer, mercury enters the food chain and can badly damage the sensitive polar ecosystem.

The mentioned events can be observed in polar spring in the Artic and Antarctic. The origin of the involved halogens is sea salt, whereas the most important halogen Bromine is released into the gas phase by autocatalytic reactions on salty snow and ice surfaces or on aerosols. As a key molecule in all chemical reaction cycles the halogen oxide BrO has been identified. It can be measured from ground and from space via satellite remote sensing by absorption spectroscopy. With the decrease of ozone and gaseous mercury an exponential increase of BrO can be observed, due to the oxidation of Bromine in the responsible chemical reactions. How these so called Bromine explosions are initialized is till now not known in detail.

The aim of this project is a better understanding of the initial Bromine release from sea salt and its subsequent transport and chemical transformation. The needed consistent time series of BrO will be obtained from different satellite instruments (GOME, SCIAMACHY, GOME2), which provide continuous observations since 1995. The influence of metrology and chemistry on the release and spreading of Br and BrO will be included by metrological model data, trajectory calculations and a chemistry model.

Scientists

Dr. Andreas Richter
Institute of Environmental Physics
University of Bremen

Mathias Begoin
Institute of Environmental Physics
University of Bremen

Prof. John P. Burrows
Institute of Environmental Physics
University of Bremen

Research areas

Northern and Southern Polar Troposphere

Publications

Theys N, Van Roozendael M, Hendrick F, Yang X, De Smedt I, Richter A, Begoin M, Errera Q, Johnston PV, Kreher K, De Mazière M, 2011. Global observations of tropospheric BrO columns using GOME-2 satellite data. Atmos. Chem. Phys. 11, 1791-1811, doi:10.5194/acp-11-1791-2011

Toyota K, McConnell JC, Lupu A, Neary L, McLinden CA, Richter A, Kwok R, Semeniuk K, Kaminski JW, Gong SL, Jarosz J, Chipperfield MP, Sioris CE, 2011. Synoptic-scale meteorological control on reactive bromine production and ozone depletion in the Arctic boundary layer: 3-D simulation with the GEM-AQ model. Atmos. Chem. Phys. 11, 3949-3979, doi:10.5194/acp-11-3949-2011

Begoin M, Richter A, Weber M, Kaleschke L, Tian-Kunze X, Stohl A, Theys N, Burrows JP, 2010. Satellite observations of long range transport of a large BrO plume in the Arctic. Atmos. Chem. Phys. 10, 6515-6526, doi:10.5194/acp-10-6515-2010

Jones AE, Anderson PS, Wolff EW, Roscoe HK, Marshall GJ, Richter A, Brough N, Colwell SR, 2010. Vertical structure of Antarctic tropospheric ozone depletion events: characteristics and broader implications. Atmos. Chem. Phys. 10, 7775-7794, doi:10.5194/acp-10-7775-2010

Jones AE, Anderson PS, Begoin M, Brough N, Hutterli MA, Marshall GJ, Richter A, Roscoe HK, Wolff EW, 2009. BrO, blizzards, and drivers of polar tropospheric ozone depletion events. Atmos. Chem. Phys. 9, 4639-4652. Zhao TL, Gong SL, Bottenheim JW, McConnell JC, Sander R, Kaleschke L, Richter A, Kerkweg A, Toyota K, Barrie LA, 2008. A three-dimensional model study on the production of BrO and Arctic boundary layer ozone depletion, J. Geophys. Res. 113, D24304, doi:10.1029/2008JD010631

Simpson WR, et al., 2007. Halogens and their role in polar boundary-layer ozone depletion, Atmos. Chem. Phys., 4375-4418.

Glasow R, et al., 2004. Impact of reactive bromine chemistry in the troposphere. Atmos. Chem. Phys. Discuss. , 4877-4913.

Kaleschke L, et al., 2004. Frost Flowers on Sea Ice as a Source of Sea Salt and their Influence on Tropospheric Halogen Chemistry. Geophysical Research Letters 31, L16114, doi:10.1029/2004GL020655.

Richter A, et al., 2002. GOME measurements of stratospheric and tropospheric BrO, Advances in Space Research 29, 1667-1672.

Richter A, et al., 1998. GOME Observations of Tropospheric BrO in Northern Hemispheric Spring and Summer 1997. Geophysical Research Letters 25, 2683-2686.

Homepage

Find more about our research on Halogens in the Polar atmosphere at http://www.doas-bremen.de/

Research funding organisation