Atmospheric black carbon and sulfate concentrations in Northeast Greenland

• Published in: Atmospheric Chemistry and Physics
• Main Authors: A. Massling, I. E. Nielsen, D. Kristensen, J. H. Christensen, L. L. Sørensen, B. Jensen, Q. T. Nguyen, J. K. Nøjgaard, M. Glasius, H. Skov
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2015
• Subjects: Physics; QC1-999; Chemistry; QD1-999; Arctic; Greenland; Station Nord; black carbon; North Greenland
• Online Access: https://doi.org/10.5194/acp-15-9681-2015; https://doaj.org/article/3ab2c533409b4b0fb528814ef99ed999

Measurements of equivalent black carbon (EBC) in aerosols at the high Arctic field site Villum Research Station (VRS) at Station Nord in North Greenland showed a seasonal variation in EBC concentrations with a maximum in winter and spring at ground level. Average measured concentrations were about 0.067 ± 0.071 for the winter and 0.011 ± 0.009 for the summer period. These data were obtained using a multi-angle absorption photometer (MAAP). A similar seasonal pattern was found for sulfate concentrations with a maximum level during winter and spring analyzed by ion chromatography. Here, measured average concentrations were about 0.485 ± 0.397 for the winter and 0.112 ± 0.072 for the summer period. A correlation between EBC and sulfate concentrations was observed over the years 2011 to 2013 stating a correlation coefficient of R 2 = 0.72. This finding gives the hint that most likely transport of primary emitted BC particles to the Arctic was accompanied by aging of the aerosols through condensational processes. BC and sulfate are known to have only partly similar sources with respect to their transport pathways when reaching the high Arctic. Aging processes may have led to the formation of secondary inorganic matter and further transport of BC particles as cloud processing and further washout of particles is less likely based on the typically observed transport patterns of air masses arriving at VRS. Additionally, concentrations of EC (elemental carbon) based on a thermo-optical method were determined and compared to EBC measurements. EBC measurements were generally higher, but a correlation between EC and EBC resulted in a correlation coefficient of R 2 = 0.64. Model estimates of the climate forcing due to BC in the Arctic are based on contributions of long-range transported BC during spring and summer. The measured concentrations were here compared with model results obtained by the Danish Eulerian Hemispheric Model, DEHM. Good agreement between measured and modeled concentrations of both EBC/BC and sulfate was ...