What happened to our smog days?

Closure of coal plants, weather patterns cited

Earlier this week the question was posed “What happened to the smog days?”

Some local environment authorities suggest the recent lack of “bad air days” is representative of Ontario’s decision to eliminate coal power. It could also be because our American neighbours are following suit by reducing coal-fired electricity generation or perhaps it’s the industrial sector making improvements and more fuel efficient cars. Maybe it’s a combination.

While we have seen a steady decline in smog days over the years, other scientists, including climate experts, believe we just haven’t had the right mix of weather to create smog — the nastylooking brown-green layer you’d typically see in the sky.

“Because it’s so complex, you can’t pinpoint one cause of pollution, eliminate it and say our air pollution is going to be perfect from now on,” said Bill Van Heyst, an environmental engineer at the University of Guelph.

“Typically, you have to have hot, sunny, stagnant air to create really bad air quality days.”

David Phillips, the popular weather guru at Environment Canada, said “we’ve had 13 days above 30 since May,”

but only one Special Air Quality Statement (SAQS) has been issued so far this year; that was June 19 when the temperature soared to 31.1 C.

Wednesday, a day you’d think a SAQS would be issued, didn’t meet the criteria despite a temperature forecast of 31 C with a humidex of 38.

The reason? Van Heyst says it was the wind.

“It dilutes the smog at a local level mixing it with clean air and that gives us a better overall air quality,” he said.

Smog happens when ground level ozone (toxic chemicals) and fine particles in the air mix with heat and sunlight. The heat allows for “faster chemical reaction” and the sunlight “produces the ozone” and if the air is still — the atmosphere turns into a pressure cooker. “It’s like a perfect storm for smog,” said Van Heyst.

Hamilton has seen plenty of smog days in its history; 2005 being the “worst year on record” for air quality, according to Van Heyst, when 45 smog advisory days were issued by the Ministry of Environment based on the Air Quality Index. In 2007, there were more than 30 and in 2012 there were 18 and no advisories in 2014.

It gives you the impression our air is much cleaner since 2005, but is it? In 2015 Environment Canada and the Ontario Ministry of the Environment and Climate Change (MOE) switched from the Air Quality Index (AQI) to the Air Quality Health Index (AQHI).

Dr. Denis Corr, chair of Clean Air Hamilton and a longtime air quality advocate (he was a provincial air expert at the Hagersville tire fire in 1990) said the new system for monitoring air pollution is “more accurate and strict,” considering direct health impacts.

“The fact is, air pollution doesn’t have any cut offs in terms of health impacts,” he said.

Corr believes the result of fewer smog days is multifaceted — there’s the elimination of coal-fired electricity, “tightening up transportation emissions” and a reduction in transboundary pollution from the U.S.

“We’ve been monitoring air quality in Hamilton for 40 years and over that time, we can brag that we’ve reduced our air pollution by 90 per cent,” he said.

But Van Heyst isn’t convinced, saying “we’re likely emitting more now then we did in 2005.”

“We’re contributing about the same amount if not more pollution into the atmosphere, it’s just dispersed more as a result of our weather patterns,” he explained.

Despite any improvements we’ve made or the weather, both agree we need to do more to minimize the health impacts caused by poor air quality. Fine particulates circulating in our air — the ones you can’t see because they’re too tiny — are still causing significant health issues. The latest data, from 2011, tells us that in Hamilton, air pollution contributes to 186 premature deaths, 395 respiratory hospital admissions and 322 cardiovascular hospital admissions every year.

“All parties; government, industry, the city, public health, stakeholders, need to come up with a fine particulate improvement strategy,” said Corr.

Van Heyst agreed but added we need to be more aggressive when it comes to everyday decisions.

“Air quality stems from our daily choices in life that dictates how or what the air pollution is going to be.

“Instead of setting the thermostat at 23 C set it at 22. People have been using cloth grocery bags for awhile now, consider where you’re buying food and transportation — transit is considered to be a less polluting method if enough people are using it. Each little act like that, does have an effect.”