Lockdowns lead to improved air quality, study shows

·3 min read

WATERLOO REGION — Hind Al-Abadleh started studying air quality during the first COVID-19 lockdown to see if it would make a difference in pollution levels in the area.

One year later, the results are in.

Al-Abadleh, a Wilfrid Laurier University chemistry professor, and her team compared 2020 with the previous three years to statistically determine which fluctuations in air quality were due to naturally or regularly occurring factors, and which were due to COVID lockdown measures.

The group focused mainly on nitrogen dioxide, which is an air pollutant that comes from combustion. Since transportation is the biggest contributor to nitrogen dioxide levels, this pollutant is a good indicator of the impact on air pollution from lockdown measures.

“Pollutant levels naturally go down when we transition from winter to spring to summer, so if you observe extra reduction, then this means that you have other factors affecting the levels. And indeed what we have noticed is that for Kitchener, in May that extra reduction was 11 per cent,” said Al-Abadleh.

“That 11 per cent is statistically significant, meaning that this reduction cannot be attributed to natural factors that contributed to what has been observed in the previous three years.”

Other statistically significant decreases in pollution over the year were noted in July at seven per cent, and October at 17 per cent.

They found that every city in southern Ontario experienced these changes in air quality uniquely. For example, while Waterloo Region saw statistically significant reductions in air pollution in May, London observed them in April, May and June.

Al-Abadleh said it’s possible London experienced a longer period of air quality improvement because it may have fewer industries considered essential that operated more consistently.

Environment Canada, along with the Ontario Ministry of Environment, Conservation and Parks, maintains a network of air quality monitoring stations across the province. Waterloo Region’s station is located at Victoria Park in Kitchener.

Data from these stations is published hourly. Al-Abadleh and her team analyzed this data for their study.

“This work put numbers on the experiences of people during the lockdown,” she said.

Air quality and climate change measures are closely related, said Al-Abadleh. When municipalities implement emission-reducing policies, the long-term result may be a reduction in carbon dioxide levels, but the short-term result is the improvement of air quality.

“That’s what I hope our study will do, that it will provide numbers for people to conceptualize what type of action they can imagine doing for their particular city because that’s the other thing that came out, is that a cookie-cutter solution is not going to work for everyone,” said Al-Abadleh.

“Every city is unique; its meteorology is unique. Therefore, their experience with measures like lockdown is going to affect the levels of pollution in their own city differently.”

Al-Abadleh said the study can be used by municipalities as a benchmark to understand concrete changes in air quality that happen as a direct result of policies.

“The data clearly shows (what happens) when humans stay home,” said Al-Abadleh. “This is an extreme measure, I mean nobody really wants to live a life like what we have lived through in the lockdown, but it’s an eye-opener.

“It’s really an eye-opener to see how much of an effect our dependency on a carbon-intense lifestyle can have on the natural systems, particularly the air that we breathe.”

Next, Al-Abadleh is looking for a sponsor to buy a mobile air quality monitoring station. This will allow Al-Abadleh and her team to gain an even more specific understanding of air quality in the region and beyond.

Leah Gerber’s reporting is funded by the Canadian government through its Local Journalism Initiative. The funding allows her to report on stories about the Grand River Watershed. Email lgerber@therecord.com

Leah Gerber, Local Journalism Initiative Reporter, Waterloo Region Record