A colder estimate of heat deaths

Lawn watering prohibited: mercury 101.3read one newspaper in Toronto. “Heat kills 100 twin townspeople” called the Saint Paul newspaper. These headlines are not from the current hotly debated heat. They are associated with the heat wave of 1936 – one of the most extreme waves of the twentieth century, according to the Environmental Protection Agency (EPA). Heat wave index. No other year since 1895 can even come close to this year in terms of intensity, and the next closest year is 1934.

By emphasizing this earlier historical episode, I do not do so to refute the claim that heat waves have been (and will continue to be) worsened by climate change. I emphasize this because it allows us to gain insight into the relationship between human well-being and climate. that the catastrophic media cannot convey.

During the heat wave of 1936, approximately 5,000 people died of heat-related causes – the death rate in 1936 was 39 per million. This number is probably too conservative. given the quality of vital records in the past compared to today. Notoriously poor vital statistics for causes of death for African Americans and poverty-induced vulnerability to these sources of death make the death toll too low. Moreover, this number also apparently does not include those who died as a result of complications caused by the heat wave.

However, let’s take this number at face value and compare it to EPA’s heat-induced death estimates for the five hottest years between 1979 and 2018: 1980, 1988, 2006, 2007, 2012. the heat wave death rate ranged from 0.86 to 2.87 per million. Scaling the EPA heat wave index to the same level as during the devastating heat wave of 1936, and assuming that the death rate increases by the same proportion, allows us to imagine the death toll from the same event occurring today. The death rate would be between 3.49 and 14.21 per million. This means that heatwaves are killing 64-91% fewer people today (in relation to the population) than in 1936.

This is an undeniable sign of our resilience to climate shocks. This does not invalidate the assertion that intensity, duration and frequency have been increasing since the 1960s. It also does not disprove the claim that climate change is driving these trends.

However, this tells us that two winds are pushing the boat towards fewer heat deaths. Headwind is climate change that explains about 37 percent (with a 20 to 76 percent confidence interval of heat-related deaths between 1991 and 2018). according to article in Nature climate change concerns a large international sample of countries.A tailwind is technological progress and economic growth that gives households the ability to protect themselves from extreme climate events.

This tailwind, which can be observed in the high share of air conditioner owners, better housing, better healthcare, access to clean and fresh water, etc., explains the lion’s share of the decline in heat-related deaths. Indeed, even if we take the upper bound of the above Nature climate change If 76 percent of deaths are attributable to climate change, climate change would have to increase the heatwave index tenfold for the death rate to exceed 10 deaths per million. No climate model suggests this possibility.

Furthermore, the death toll from heat waves is only slightly lower than the number of cold-related deaths. Thus, climate change may increase the former but decrease the latter, creating an ambiguous net effect on mortality from extreme climate events. Some studies suggest that eventually the total number of deaths will decrease. Others suggest more deaths overall. Which set of studies is correct, however, does not matter. Indeed, the tailwind that reduced heat mortality also reduced cold mortality.

The pursuit of sensational headlines predicting doom and gloom is doing us a disservice. It obscures the progress we have made in the past and prevents us from using this history to guide public discussion. Journalists and experts should keep this in mind before trying to use the current event to gain attention.

Vincent Geloso

Vincent Geloso

Vincent Geloso, AIER Senior Fellow, Associate Professor of Economics at Queen’s University College. He received his PhD in economic history from the London School of Economics.

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