References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-7-511-2007

Arctic smoke – record high air pollution levels in the European Arctic due to agricultural fires in Eastern Europe in spring 2006

Stohl

¹ Berg

¹ ¹¹ Burkhart

J. F.

¹ ² Fjǽraa

A. M.

¹ Forster

¹ Herber

³ Hov

Ø.

⁴ Lunder

¹ McMillan

W. W.

⁵ Oltmans

⁶ Shiobara

⁷ Simpson

⁴ Solberg

¹ Stebel

¹ Ström

⁸ Tørseth

¹ Treffeisen

³ Virkkunen

⁹ ¹⁰ Yttri

K. E.

Norwegian Institute for Air Research, Kjeller, Norway

University of California, Merced, USA

Alfred Wegener Institute, Bremerhaven, Germany

Meteorological Institute, Oslo, Norway

University of Maryland, Baltimore, USA

Earth System Research Laboratory, NOAA, Boulder, USA

National Institute of Polar Research, Tokyo, Japan

Department of Applied Environmental Science, Stockholm University, Sweden

Arctic Centre, University of Lapland, Finland

Department of Chemistry, University of Oulu, Oulu, Finland

now at: Norwegian University of Science and Technology, Trondheim, Norway

26 01 2007

7 2 511 534

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.

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The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/511/2007/acp-7-511-2007.pdf

In spring 2006, the European Arctic was abnormally warm, setting new historical temperature records. During this warm period, smoke from agricultural fires in Eastern Europe intruded into the European Arctic and caused the most severe air pollution episodes ever recorded there. This paper confirms that biomass burning (BB) was indeed the source of the observed air pollution, studies the transport of the smoke into the Arctic, and presents an overview of the observations taken during the episode. Fire detections from the MODIS instruments aboard the Aqua and Terra satellites were used to estimate the BB emissions. The FLEXPART particle dispersion model was used to show that the smoke was transported to Spitsbergen and Iceland, which was confirmed by MODIS retrievals of the aerosol optical depth (AOD) and AIRS retrievals of carbon monoxide (CO) total columns. Concentrations of halocarbons, carbon dioxide and CO, as well as levoglucosan and potassium, measured at Zeppelin mountain near Ny Ålesund, were used to further corroborate the BB source of the smoke at Spitsbergen. The ozone (O3) and CO concentrations were the highest ever observed at the Zeppelin station, and gaseous elemental mercury was also elevated. A new O3 record was also set at a station on Iceland. The smoke was strongly absorbing – black carbon concentrations were the highest ever recorded at Zeppelin – and strongly perturbed the radiation transmission in the atmosphere: aerosol optical depths were the highest ever measured at Ny Ålesund. We furthermore discuss the aerosol chemical composition, obtained from filter samples, as well as the aerosol size distribution during the smoke event. Photographs show that the snow at a glacier on Spitsbergen became discolored during the episode and, thus, the snow albedo was reduced. Samples of this polluted snow contained strongly elevated levels of potassium, sulphate, nitrate and ammonium ions, thus relating the discoloration to the deposition of the smoke aerosols. This paper shows that, to date, BB has been underestimated as a source of aerosol and air pollution for the Arctic, relative to emissions from fossil fuel combustion. Given its significant impact on air quality over large spatial scales and on radiative processes, the practice of agricultural waste burning should be banned in the future.

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