Articles | Volume 22, issue 22
https://doi.org/10.5194/acp-22-14631-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-22-14631-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Nov 2022
Research article |
| 18 Nov 2022
| 18 Nov 2022
Long-term declines in atmospheric nitrogen and sulfur deposition reduce critical loads exceedances at multiple Canadian rural sites, 2000–2018
Irene Cheng
CORRESPONDING AUTHOR
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Zhuanshi He
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Hazel Cathcart
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Daniel Houle
Aquatic Contaminants Research Division, Water Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Montréal, Quebec H2Y 2E7, Canada
Amanda Cole
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Jian Feng
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Jason O'Brien
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Anne Marie Macdonald
Air Quality Research Division, Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
Julian Aherne
School of Environment, Trent University, Peterborough, Ontario K9L 0G2, Canada
Jeffrey Brook
Dalla Lana School of Public Health and Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5T 3M7, Canada
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Short summary
Nitrogen (N) and sulfur (S) deposition decreased significantly at 14 Canadian sites during 2000–2018. The greatest decline was observed in southeastern Canada owing to regional SO2 and NOx reductions. Wet deposition was more important than dry deposition, comprising 71–95 % of total N and 45–89 % of total S deposition. While critical loads (CLs) were exceeded at a few sites in the early 2000s, acidic deposition declined below CLs after 2012, which signifies recovery from legacy acidification.
Nitrogen (N) and sulfur (S) deposition decreased significantly at 14 Canadian sites during...
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