Impact of summertime anthropogenic emissions on atmospheric black carbon at Ny-Ålesund in the Arctic

Abstract

Measurements of equivalent black carbon (EBC), calculated from aethalometer measurements of light attenuation, were carried out in July 2011 at Ny-Ålesund in the Arctic. Highly elevated EBC concentrations were observed within the settlement of Ny-Ålesund, with a median value of 17 ng m⁻³, which was about two times the background level. Results from the ensemble empirical mode decomposition method suggested that about 60–80% of atmospheric EBC concentrations at Ny-Ålesund were from local emissions, while only 20–40% arrived via atmospheric transport. The estimated average local emission rate was 8.1 g h⁻¹, with an uncertainty of approximately a factor of two. The pollution plume was confined to 10 km downwind of the settlement, with the total EBC deposition estimated to be 6.4–44 ng m⁻² h⁻¹. This may affect snow black carbon (BC) concentrations in nearby glaciated areas. The efficiencies of the long-range transport were estimated based on cluster analysis and potential precipitation contribution function, and the results implied that transport from western Europe is more efficient than from central Russia, on account of relatively rapid transport from western Europe and infrequent precipitation along this route. However, there was no correlation between air mass back-trajectories and EBC concentrations, suggesting that the contribution of long-range transport to EBC measured in Ny-Ålesund might be not significant in this season.

• Equivalent black carbon
• Ny-Ålesund
• human influences
• transport efficiency.

Acknowledgements

This work was funded by the National Natural Science Foundation of China (grant no. 41105094) and the Scientific Research Foundation of Third Institute of Oceanography, State Oceanic Administration of China (grant no. 2011004). The Chinese Arctic and Antarctic Administration of State Oceanic Administration supported field accommodations at YRS. The authors thanks W. Li for technical assistance and L. Chen for encouragement. The authors are also grateful for a full-time graduate assistantship provided by Rutgers University that supported the continuation and completion of this research. We gratefully acknowledge the US National Oceanic and Atmospheric Administration's Air Resources Laboratory for providing the HYSPLIT transport and dispersion model, and ECMWF and NCAR/NCEP for providing the meteorological data freely. We thank Elisabeth Bjerke Råstad at Kings Bay AS for supplying the harbour log. We thank the two reviewers for their valuable comments on this manuscript.