A study by scientists at the Columbia University Climate School has found that the weather conditions driven by climate change that are increasing the occurrence of wildfires are playing a growing role in shaping summer air quality in both the United States and Canada. And the news isn’t good. The air is getting smokier and the impact on public health is not something that can be addressed by regulatory action, as was the case for fossil fuel pollution.
The study looked at air quality data over the past 70 years. From the 1970s until the early 2000s, air quality improved in the eastern part of the US and Canada as sulfur dioxide and nitrogen oxide emissions came under air-quality regulations. Cleaner industrial operations and reduced vehicle emissions helped improve air quality.
But over the past 25 years, the opposite trend began as more severe wildfires and greater burned areas contributed to increased summertime smoke. 2023 had the highest smoke levels in 20 years of satellite measurements and the most smoke and haze reports in 70 years of surface observations.
Twelve out of Canada’s 13 provinces and territories set new records for wildfire smoke in 2023. Only about half as much burned last year, but that would still be record-setting for any other year.
As the climate continues to warm, wildfires will continue to increasingly occur. Better smoke monitoring and forecasting can help communities prepare when air quality is expected to worsen. Long term, broader public health measures such as home filtration and public clean-air shelters will be increasingly important.
