Record-breaking August
Month ‘notably warmer than normal’ throughout province
Toronto’s steamy August will likely become the city’s hottest on record.
“Toronto is on pace to have its warmest August ever,” Environment Canada meteorologist Geoff Coul son told the National Post this week. “The average temperature for this August at Pearson is 24.4 Celsius, while the record for warmest August was 23.8 Celsius in 1959.”
On August 10, temperatures in Toronto hit to 35.6C, tying the record set back in 1944. Some days felt as hot as 44C with the humidex.
Coulson added that “all of southern, eastern, central and northeastern Ontario have been notably warmer than normal.” London, Ont., will also likely experience its warmest August since 1959.
The above-average temperatures followed a scorching July in Toronto, when temperatures reached at least 30 degrees on 14 days.
For passengers riding on Toronto’s sub ways, the combination of unbearable heat and no air-conditioning on roughly one quarter of trains made travel sticky and uncomfortable. Toronto Mayor John Tory recently accepted a Twitter challenge to ride on one of the TTC’s trains sans airconditioning. Sweltering commuters endured temperatures as high as 34 C in some subway cars.
GO Transit had to slow down its trains throughout the summer, adding delay times to their schedules. The change was a safety precaution, as areas on train tracks can bend and buckle under the extreme heat, and increase the risk of derailment for fast-moving trains.
The record temperatures in Ontario can also have significant health costs. A Health Canada study of five large Canadian cities found that high temperatures during June, July and August are correlated with increased deaths. One large-scale U.S. study of more than 850,000 people in California found that a roughly six-degree increase in average temperatures corresponded to a 3.5 per cent increase in strokes, a 2 per cent increase in all respiratory diseases, a 3.7 per cent increase in pneumonia, and a 10.8 per cent increase in dehydration.
Heat impacts on health are worse when high temperatures continue throughout the day and night. For nearly one quarter of all people in Ontario who do not have an airconditioning system, warm nights are a barrier to finding relief from daytime heat. Households making less than $20,000 a year are the least likely to have access to cool space.
On especially warm days, cities like Toronto can become “urban heat islands” — places where air temperatures are a few degrees higher than surrounding areas. Urbanized areas tend to be built from dark, non-reflective materials that absorb radiation from the sun and gradually release the additional heat.
In 1936, summer temperatures in the mid-40s in Manitoba and Ontario caused the deaths of 1,180 people, making it the deadliest heat wave in Canadian history. Nearly a third of those who died drowned while trying to find relief.
Now 80 years later, Toronto has fully implemented a “Harmonized Heat Warning and Information System.” During the heat warnings, the city opens up seven cooling centres to help people stay cool. Officials at Toronto Public Health say that they are working to protect groups that are most at risk from the heat, especially older people, people with heart and lung conditions, infants and young children, and homeless people.
Earlier this month, the city declared a heat warning which lasted two days, followed by a fiveday extended heat warning that ended on August 9. Warnings are issued if forecast temperatures are higher than 31 C for two consecutive days.
Based on Toronto’s climate driver study, by 2050 the city could see maximum daily temperatures rise to 44 C, up from 37 C, and four times as many extended heatwaves per year.