Research Scientist, Department of Atmospheric and Climate Research
NILU Norwegian Institute for Air Research
PO Box 100, N-2027 Kjeller, Norway
phone + 47 - 6389 8187, fax + 47 - 6389 - 8050,
Record high peaks in PCBs due to atmsopheric long-range transport of biomass burning emissions
|Courtesy Ann-Christine Engvall, view from measurement station Zeppelin during (non) fire influenced period|| Soils and forests in the boreal region of the northern hemisphere
are recognised as having a large capacity for storing air-borne
Persistent Organic Pollutants (POPs), such as the polychlorinated
biphenyls (PCBs). Following reductions of primary emissions of various
legacy POPs, there is an increasing interest and debate about the
relative importance of secondary re-emissions on the atmospheric levels
of POPs. In spring of 2006, biomass burning (BB) emissions from
agricultural fires in Eastern Europe were transported to the Zeppelin
station on Svalbard, where record-high levels of many air pollutants
were recorded. Here we report on the extremely high concentrations of
PCBs that were also measured during this period. 21 out of 32 PCB
congeners were enhanced by more than two standard deviations above the
long-term mean concentrations. In July 2004, about 5.8 million hectare
of boreal forest burned in North America, emitting a pollution plume
which reached the Zeppelin station after a travel time of 3-4 weeks.
Again, 12 PCB congeners were elevated above the long-term mean by more
than two standard deviations, with the less chlorinated congeners being
most strongly affected. We propose that these abnormally high
concentrations were caused by BB emissions.
Eckhardt, S., K. Breivik, S. Manoe, A. Stohl: Record high peaks in PCB concentrations in the Arctic atmosphere due to long-range transport of biomass burning emissions, Atmos. Chem. Phys. , 7, 4527-4536, 2007.
|Transport Pathways as derived from a 15-Year Climatology of Tracer Transport|
|Transport pathways derived from the 15-year climatology of tracer
transport as simulated with FLEXPART.
The green arrows show typical transport pathways below 3 km and the black
arrows indicate pathways above 3 km. These transport pathways show differences
during extreme phases of the North Atlantic Oscillation. During high phases
of the NAO more tracer is found in the Arctic. Movies of tracer
transport are shown at: http://www.forst.tu-muenchen.de/EXT/LST/METEO/arcticpollution/
More information can be found in:
Eckhardt, S., A. Stohl, S. Beierle, N. Spichtinger, P. James, C. Forster, C. Junker, T. Wagner, U. Platt, and S. G. Jennings, 2003: The North Atlantic Oscillation controls air pollution transport to the Arctic, Atmos. Chem. Phys., 3, 1769-1778, 2003.
|A 15-Year Climatology of Warm Conveyor Belts|
|Eckhardt, S., A, Stohl, H. Wernli, P. James, C. Forster and N. Spichtinger, A 15-Year Climatology of Warm Conveyor Belts, J. Climate, 17, 218-237, 2004.|