ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-12-3241-2012 Atmospheric mercury observations from Antarctica: seasonal variation and source and sink region calculations Pfaffhuber K. A. 1 Berg T. 1 2 Hirdman D. 1 3 Stohl A. 1 Norwegian Institute for Air Research (NILU), Kjeller, Norway current address: Department of Chemistry, Norwegian University of Science and Technology, Trondheim, Norway current address: Centre for Environmental and Climate Research (CEC), Lund University, Lund, Sweden 03 04 2012 12 7 3241 3251 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/12/3241/2012/acp-12-3241-2012.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/12/3241/2012/acp-12-3241-2012.pdf

Long term atmospheric mercury measurements in the Southern Hemisphere are scarce and in Antarctica completely absent. Recent studies have shown that the Antarctic continent plays an important role in the global mercury cycle. Therefore, long term measurements of gaseous elemental mercury (GEM) were initiated at the Norwegian Antarctic Research Station, Troll (TRS) in order to improve our understanding of atmospheric transport, transformation and removal processes of GEM. GEM measurements started in February 2007 and are still ongoing, and this paper presents results from the first four years. The mean annual GEM concentration of 0.93 ± 0.19 ng m<sup>−3</sup> is in good agreement with other recent southern-hemispheric measurements. Measurements of GEM were combined with the output of the Lagrangian particle dispersion model FLEXPART, for a statistical analysis of GEM source and sink regions. It was found that the ocean is a source of GEM to TRS year round, especially in summer and fall. On time scales of up to 20 days, there is little direct transport of GEM to TRS from Southern Hemisphere continents, but sources there are important for determining the overall GEM load in the Southern Hemisphere and for the mean GEM concentration at TRS. Further, the sea ice and marginal ice zones are GEM sinks in spring as also seen in the Arctic, but the Antarctic oceanic sink seems weaker. Contrary to the Arctic, a strong summer time GEM sink was found, when air originates from the Antarctic plateau, which shows that the summertime removal mechanism of GEM is completely different and is caused by other chemical processes than the springtime atmospheric mercury depletion events. The results were corroborated by an analysis of ozone source and sink regions.

 References Ashbaugh, L. L.: A statistical trajectory technique for determining air pollution source regions, J. Air Poll. Contr. Ass., 33, 1096–1098, 1983. Ashbaugh, L. L., Malm, W. C.and Sadeh, W. Z.: A residence time probability analysis of sulphur concentrations at Grand Canyon National Park, Atmos. Environ., 19, 1263–1270, 1985. Aspmo, K., Gauchard, P. A., Steffen, A., Temme, C., Berg, T., Bahlmann, E., Banic, C., Dommergue, A., Ebinghaus, R., Ferrari, C., Pirrone, N., Sprovieri, F., and Wibetoe, G.: Measurements of atmospheric mercury species during an international study of mercury depletion events at Ny-Ålesund, Svalbard, spring 2003. How reproducible are our present methods?, Atmos. Environ., 39, 7607–619, 2005. Bargagli, R., Agnorelli, C., Borghini F., and Monaci, F.: Enhanced deposition and bioaccumulation of mercury in Antarctic terrestrial ecosystems facing a coastal polynya, Environ. Sci. Technol., 39, 8150–8155, 2005. Berg, T., Sekkesaeter, S., Steinnes, E., Valdal, A. K., and Wibetoe, G.: Springtime depletion of mercury in the European Arctic as observed at Svalbard, Sci. Total Environ., 304, 43–51, 2003. Berg, T., Pfaffhuber, K. A., Cole, A., and Steffen, A.: Long-term atmospheric mercury measurements in the Norwegian Arctic: trend analysis, in preparation, 2011. Bergstrom, D. M., Convey, P. and Huiskes, A. H. L.: Trends in Antarctic Terrestrial and Limnetic Ecosystems, 369~pp., Springer, Dordrecht, The Netherlands, 2006. Bloss, W. J., Lee, J. D., Heard, D. E., Salmon, R. A., Bauguitte, S. J.-B., Roscoe, H. K., and Jones, A. E.: Observations of OH and HO<sub>2</sub> radicals in coastal Antarctica, Atmos. Chem. Phys., 7, 4171–4185, http://dx.doi.org/10.5194/acp-7-4171-2007doi:10.5194/acp-7-4171-2007, 2007. Brooks, S., Lindberg, S., Southworth, G. and Arimoto, R.: Springtime atmospheric mercury speciation in the McMurdo, Antarctica coastal region, Atmos. Environ., 42, 2885–2893, 2008a. Brooks, S., Arimoto, R., Lindberg, S., and Southworth, G.: Antarctic polar plateau snow surface conversion of deposited oxidized mercury to gaseous elemental mercury with fractional long-term burial, Atmos. Environ., 42, 2877–2884, 2008b. Brunke, E.-G., Labuschagne, C., Ebinghaus, R., Kock, H. H., and Slemr, F.: Gaseous elemental mercury depletion events observed at Cape Point during 2007–2008, Atmos. Chem. Phys., 10, 1121–1131, http://dx.doi.org/10.5194/acp-10-1121-2010doi:10.5194/acp-10-1121-2010, 2010. Cole, A., Steffen, A., Poissant, L., Pilote, M., Pfaffhuber, K. A., and Berg, T.: Trends in atmospheric mercury concentrations in the northern hemisphere: Why is the arctic different?, Abstract submitted to the 10th International Conference on Mercury as a Global Pollutant, 7 Halifax, Canada, 24–29 July 2011, RS4–P5, 2011. Crawford, J. H., Davis, D. D., Chen, G., Buhr, M., Oltmans, S., Weller, R., Mauldin, L., Eisele, F., Shetter, R., Lefer, B., Arimoto, R., and Hogan A.: Evidence for photochemical production of ozone at the South Pole surface, Geophys. Res. Lett., 28, 3641–3644, http://dx.doi.org/10.1029/2001GL013055doi:10.1029/2001GL013055, 2001. Davis, D., Chen, G., Buhr, M., Crawford, J., Lenschow, D., Lefer, B., Shetter, R., Eisele, F., Mauldin, L. and Hogan, A.: South Pole NO<sub>x</sub> Chemistry: an assessment of factors controlling variability and absolute levels, Atmos. Environ., 38, 5375–5388, 2004. Davis, D. D., Seelig, J., Huey, G., Crawford, J., Chen, G., Wang, Y., Buhr, M., Helmig, D., Neff, W., Blake, D., Arimoto, R., and Eisele, F.: A reassessment of Antarctic Plateau reactive nitrogen based on ANTCI 2003 airborne ground based measurements, Atmos. Environ., 42, 2831–2848, 2008. Dommergue, A., Sprovieri, F., Pirrone, N., Ebinghaus, R., Brooks, S., Courteaud, J., and Ferrari, C. P.: Overview of mercury measurements in the Antarctic troposphere, Atmos. Chem. Phys., 10, 3309–3319, http://dx.doi.org/10.5194/acp-10-3309-2010doi:10.5194/acp-10-3309-2010, 2010. Ebinghaus, R., Kock, H. H., Temme, C., Einax, J. W., Lowe, A. G., Richter, A., Burrows, J. P., and Schroeder, W. H.: Antarctic springtime depletion of atmospheric mercury, Environ. Sci. Technol., 36, 1238–1244, 2002. Hansen, G., Aspmo. K., Berg, T., Edvardsen, K., Fiebig, M., Kallenborn, R., Krognes, T., Lunder, C., Stebel., K., Schmidbauer, N., Solberg, S., and Yttri, K. E.: Atmospheric monitoring at the Norwegian Antarctic Station Troll: Measurement programme and first results, Polar Res., 28, 353–363, 2009. Hirdman, D., Aspmo, K., Burkhart, J.F., Eckhardt, S., Sodemann, H., and Stohl, A.: Transport of mercury in the Arctic atmosphere: Evidence of a spring-time sink and summer-time source, Geophys. Res. Lett., 36, L12814, http://dx.doi.org/10.1029/2009GL038345doi:10.1029/2009GL038345, 2009. Hirdman, D., Sodemann, H., Eckhardt, S., Burkhart, J. F., Jefferson, A., Mefford, T., Quinn, P. K., Sharma, S., Ström, J., and Stohl, A.: Source identification of short-lived air pollutants in the Arctic using statistical analysis of measurement data and particle dispersion model output, Atmos. Chem. Phys., 10, 669–693, http://dx.doi.org/10.5194/acp-10-669-2010doi:10.5194/acp-10-669-2010, 2010. Holmes, C. D., Jacob, D. J., Corbitt, E. S., Mao, J., Yang, X., Talbot, R., and Slemr, F.: Global atmospheric model for mercury including oxidation by bromine atoms, Atmos. Chem. Phys., 10, 12037–12057, http://dx.doi.org/10.5194/acp-10-12037-2010doi:10.5194/acp-10-12037-2010, 2010. Kaleschke, L., Richter, A., Burrows, J., Afe, O., Heygster, G., Notholt, J., Rankin, A. M., Roscoe, H. K., Hollwedel, J. Wagner, T., and Jacobi, H.-W.: Frost flowers on sea ice as a source of sea salt and their influence on tropospheric halogen chemistry, Geophys. Res. Lett., 31, L16114, http://dx.doi.org/10.1029/2004GL020655doi:10.1029/2004GL020655, 2004. Lindberg, S. E., Brooks, S., Lin, C. J., Scott, K. J., Landis, M. S., Stevens, R. K., Goodsite, M., and Richter, A.: Dynamic oxidation of gaseous mercury in the Arctic troposphere at polar sunrise, Environ. Sci. Technol., 39, 1245–1256, 2002. Pacyna, E. G., Pacyna, J. M., Steenhuisen, F., and Wilson, S.: Global anthropogenic mercury emission inventory for 2000, Atmos. Environ., 40, 4048–4063, 2006. Pacyna, E. G., Pacyna, J. M., Sundseth, K., Munthe, J., Kindbom, K., Wilson, S., Steenhuisen, F., and Maxon, P.: Global emission of mercury to the atmosphere from anthropogenic sources and projection to 2020, Atmos. Environ., 44, 2487–2499, 2010. Priddle, J (Ed).: Regionally based assessment of persistent toxic substances – Antarctica regional report, United Nations Environmental Programme – Chemicals, Geneva, Switzerland, 76~pp., 2002. Schroeder, W. H. and Munthe, J.: Atmospheric mercury – an overview, Atmos. Environ., 32, 809–822, 1995. Schroeder, W. H., Anlauf, K. G., Barrie, L. A., Lu, J. Y., Steffen, A., Schneeberger, D. R., and Berg, T.: Arctic springtime depletion of mercury, Nature, 394, 331–332, 1998. Simpson, W. R., Carlson, D., Hönninger, G., Douglas, T. A., Sturm, M., Perovich, D., and Platt, U.: First-year sea-ice contact predicts bromine monoxide (BrO) levels at Barrow, Alaska better than potential frost flower contact, Atmos. Chem. Phys., 7, 621–627, http://dx.doi.org/10.5194/acp-7-621-2007doi:10.5194/acp-7-621-2007, 2007. Slemr, F., Brunke, E.-G., Ebinghaus, R., Temme, C., Munthe, J., Wangberg, I., Schroeder, W., Steffen, A., and Berg, T.: Worldwide trend of atmospheric mercury since 1977, Geophys. Res. Lett., 30, 1516, http://dx.doi.org/10.1029/2003GL016954doi:10.1029/2003GL016954, 2003. Slemr, F., Brunke, E.-G., Labuschagne, C., and Ebinghaus, R.: Total gaseous mercury concentration at the Cape Point GAW stations and their seasonality, Geophys. Res. Lett., 35, L11807, http://dx.doi.org/10.1029/2008GL033741doi:10.1029/2008GL033741, 2008. Slemr, F., Brunke, E.-G., Ebinghaus, R., and Kuss, J.: Worldwide trend of atmospheric mercury since 1995, Atmos. Chem. Phys., 11, 4779–4787, http://dx.doi.org/10.5194/acp-11-4779-2011doi:10.5194/acp-11-4779-2011, 2011. Sprovieri, F., Pirrone, N., Hedgecock, I. M., Landis, M. S. and Stevens, R. K.: Intensive atmospheric mercury measurements at Terra Nova Bay in Antarctica during November and December 2000, J. Geophys. Res., 107, 4722, http://dx.doi.org/10.1029/2002JD002057doi:10.1029/2002JD002057, 2002. Steffen, A., Douglas, T., Amyot, M., Ariya, P., Aspmo, K., Berg, T., Bottenheim, J., Brooks, S., Cobbett, F., Dastoor, A., Dommergue, A., Ebinghaus, R., Ferrari, C., Gardfeldt, K., Goodsite, M. E., Lean, D., Poulain, A. J., Scherz, C., Skov, H., Sommar, J., and Temme, C.: A synthesis of atmospheric mercury depletion event chemistry in the atmosphere and snow, Atmos. Chem. Phys., 8, 1445–1482, http://dx.doi.org/10.5194/acp-8-1445-2008doi:10.5194/acp-8-1445-2008, 2008. Stohl, A. and Sodemann, H.: characteristics of atmospheric transport into the Antarctic troposphere, J. Geophys. Res., 112, D02305, dio:10.1029/2009JD012536, 2010. Stohl, A., Hittenberger, M., and Wotawa, G.: Validation of the Lagrangian particle dispersion model FLEXPART against large scale tracer experiment data, Atmos. Environ., 32, 4245–4264, 1998. Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa, G.: Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2, Atmos. Chem. Phys., 5, 2461–2474, http://dx.doi.org/10.5194/acp-5-2461-2005doi:10.5194/acp-5-2461-2005, 2005. Temme, C., Einax, J. W., Ebinghaus, R., and Schroeder, W. H.: Measurements of atmospheric mercury species at a coastal site in the Antarctic and over the South Atlantic Ocean during polar summer, Environ. Sci. Technol., 37, 22–31, 2003a. Temme, C., Slemr, F., Ebinghaus, R. and Einax, J.W.: Distribution of mercury over the Atlantic Ocean in 1996 and 1999–2001, Atmos. Environ., 37, 1889–1897, 2003b. Xia, C., Xie, Z., and Sun, L: Atmospheric mercury in the marine boundary layer along a cruise path from Shanghai, China to Prydz Bay, Antarctica, Atmos. Environ., 44, 1815–1821, 2010.