Extreme heat is here to stay. Canada must adapt.

The blazing temperatures across the country should be a wake-up call to the imminent health crisis facing Canadians. Extreme heat events have increased in intensity and frequency as anthropogenic climate change takes hold: A recent study found that almost 300,000 people older than 65 died of heat-related causes in 2018, an increase of 54 per cent since 2000. At the time of writing, coroners estimate that between June 25 and July 1 of this year, 808 people died during British Columbia’s record-breaking heat wave.

Extreme weather events  are expected to increase in the coming decade, but according to a recent government report, Canada remains unprepared. David Phillips, senior climatologist at Environment Canada, warns that the recent heat wave is “really a dress rehearsal, almost the opening act of what we’re going to see more of.”

As the planet heats up, extreme weather is felt unequally. Both across and within countries, rising temperatures and extreme heat events create and exacerbate health inequities. The elderly, children and people with chronic diseases or who are on certain medications are the most sensitive to heat.

But a purely physiological perspective on heat illness and mortality grossly underestimates the importance of social factors in determining who lives and who dies when the mercury climbs.

People experiencing homelessness, essential workers, those with disabilities and individuals from low socio-economic groups are more vulnerable to extreme heat. Limited access to cooling resources, health care and necessary supplies can all impact survival.

For example, when a 1995 heat wave killed more than 720 residents in Chicago, urban sociologist Eric Klinenberg found that Black and senior residents living on their own were at higher risk of death as deteriorating public housing, public spaces and high crime rates in certain neighbourhoods left residents isolated. Likewise, environmental historian Richard Keller’s analysis of the French heat wave in 2003 that left 15,000 dead outlined how social isolation of senior residents, a decline in state services and the distinct Parisian infrastructure left the elderly to die alone in the heat under the iconic zinc roofs of Paris.

Like the COVID-19 pandemic, heat waves put existing systems of social and material infrastructure under pressure and reveal social fault lines. Higher rates of illness and mortality are exposed along the lines of income, education, race, disability and living and working environments. There is an urgent need to address deprivations in both material and social infrastructure by health and social policy-makers and urban designers.

The recent heat wave is “really a dress rehearsal, almost the opening act of what we’re going to see.”

There is scope for action across three main areas.

First, action plans often focus on short-term measures, such as providing air-conditioned shelters, whereas long-term adaptation in housing design and urban planning is needed. In 2015, the World Health Organization issued its first heat action guidance and many countries have drawn up action plans with different interventions. For example, governments can extend opening hours and availability of public places that provide accessible shelter, issue warnings with behavioural and health advice, and prepare hospitals for the expected surge in heat-related emergencies.

Second, measures are often insular and focused on the health-care sector and do not consider the role of social vulnerability and social policies. The pandemic has drawn attention to the importance of the social determinants of health within our universal health system. This heat wave should hammer home the importance of social inclusion within “building back better” as we prepare for hotter temperatures.

Third, current cooling practices add further fuel to climate change. Air conditioner sales are up 60 per cent, according to some Canadian reports, and the World Bank estimates that global energy use for cooling will triple until 2050. These units are not only sources of emissions but can also fail to cool residents amid demand-induced power outages during heat waves. As Canada takes on the heat, it must consider sustainable forms of cooling and draw lessons from research such as Oxford’s Future of Cooling Programme and countries like Singapore that have long researched and adapted to heat.

We tend to view heat waves as unpreventable natural disasters. But this Canadian heat wave illustrates the two-fold human responsibility for heat-related mortality: decades of unabated greenhouse gas emissions that helped create the heat dome and forms of social and material deprivation that contributed to preventable heat-related deaths.

It is time to address the health inequalities of extreme heat events and climate change by collecting reliable and comprehensive data on physiological and social risk factors and by taking an integrated long-term approach to heat action planning in Canada.

The comments section is closed.

  • wayne maksylewich says:

    Sigh. Two Rhodes humanities scholars weighing in on climate change — and getting it wrong. First, cold kills 20x more people every year than cold – even the CBC News gets that (see May 20, 2015 Killer cold: why heat waves get too much attention). Second, stop confusing weather with climate and improve your understanding of outlier events. Journalists have been citing a recent and paper (un-reviewed) which purportedly says climate warming increased the “heat dome” probability by 150 times. The authors used attribution analysis and actually identified 2 potential causes of the heat event – an outlier or climate change. Why does everyone bail into climate pool? I also note the paper did no analysis of site specific historical events to establish whether the temperatures were statistically outside of predictability – a Bayesian analysis with a flat prior is recommended.

    In the faint hope of remedying prejudices, I suggest some reading. See
    Cliff Mass – a university professor and climate modeller – gives a lay understandable discussion of the western north American heat wave and climate attribution studies. Second read Steve Koonin’s book Unsettled – What Climate Science Tells Us and Doesn’t. He was Obama’s climate expert. At least read chapter 4 on the perils of modeling and chapter 5 on temperatures.

    You might also benefit from reference to some anthropological studies by Dr Fagan on the history and impact of normal climate variability on numerous human civilizations, and indeed on human evolution:
    – The long summer How climate changed civilization
    – Cro-Magnon How the Ice Age Gave Birth to the First Modern Humans
    – The Little Ice Age How Climate Made History 1300-1850

    To fill a couple of gaps, I have a couple of advanced engineering degrees, and decades of experience in mathematical modeling and energy conservation. While retired, I also keep current with climate issues.

  • Lex Bauer says:


  • Heinrich Kröger says:

    Sehr guter Beitrag! Wir müssen viel mehr tun, um die Klimakatastrophe noch irgendwie in den Griff zu bekommen. In Deutschland gab es letzte Woche verheerende Regenfälle, ebenso wie in China. Ganze Häuser und Regionen sind zerstört. Begreifen wir es jetzt endlich: Es ist nicht mehr 5 vor 12, sondern eher schon 1 vor zwölf.
    Heinrich Kroeger


Carolin Kroeger


Carolin Kroeger is a Rhodes Scholar originally from Luenen, Germany, and a DPhil student focusing on the social and health inequities of heat in the Department of Social Policy and Intervention at the University of Oxford.

Sara Rotenberg


Sara Rotenberg is a disabled advocate and DPhil student in the Nuffield Department of Primary Care Health Sciences at the University of Oxford, where she studies as a Rhodes Scholar. She is originally from Toronto.

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