Assessing the impact of shipping emissions on air pollution in the Canadian Arctic and northern regions: current and future modelled scenarios

• Published in: Atmospheric Chemistry and Physics
• Main Authors: W. Gong, S. R. Beagley, S. Cousineau, M. Sassi, R. Munoz-Alpizar, S. Ménard, J. Racine, J. Zhang, J. Chen, H. Morrison, S. Sharma, L. Huang, P. Bellavance, J. Ly, P. Izdebski, L. Lyons, R. Holt
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2018
• Subjects: Physics; QC1-999; Chemistry; QD1-999; Arctic; black carbon; Climate change; Sea ice
• Online Access: https://doi.org/10.5194/acp-18-16653-2018; https://doaj.org/article/3c2cf40b92594e3c9663a3a65b072f29

A first regional assessment of the impact of shipping emissions on air pollution in the Canadian Arctic and northern regions was conducted in this study. Model simulations were carried out on a limited-area domain (at 15 km horizontal resolution) centred over the Canadian Arctic, using the Environment and Climate Change Canada's on-line air quality forecast model, GEM-MACH (Global Environmental Multi-scale – Modelling Air quality and CHemistry), to investigate the contribution from the marine shipping emissions over the Canadian Arctic waters (at both present and projected future levels) to ambient concentrations of criteria pollutants (O 3 , PM 2.5 , NO 2 , and SO 2 ), atmospheric deposition of sulfur (S) and nitrogen (N), and atmospheric loading and deposition of black carbon (BC) in the Arctic. Several model upgrades were introduced for this study, including the treatment of sea ice in the dry deposition parameterization, chemical lateral boundary conditions, and the inclusion of North American wildfire emissions. The model is shown to have similar skills in predicting ambient O 3 and PM 2.5 concentrations in the Canadian Arctic and northern regions, as the current operational air quality forecast models in North America and Europe. In particular, the model is able to simulate the observed O 3 and PM components well at the Canadian high Arctic site, Alert. The model assessment shows that, at the current (2010) level, Arctic shipping emissions contribute to less than 1 % of ambient O 3 concentration over the eastern Canadian Arctic and between 1 and 5 % of ambient PM 2.5 concentration over the shipping channels. Arctic shipping emissions make a much greater contributions to the ambient NO 2 and SO 2 concentrations, at 10 %–50 % and 20 %–100 %, respectively. At the projected 2030 business-as-usual (BAU) level, the impact of Arctic shipping emissions is predicted to increase to up to 5 % in ambient O 3 concentration over a broad region of the Canadian Arctic and to 5 %–20 % in ambient PM 2.5 concentration over ...