To reach this conclusion, researchers at Dartmouth University (USA) combined economic data with weather data for the five hottest days of the year in regions around the world.
The results indicate that between 1992 and 2013, heatwaves statistically coincided with changes in economic growth and that the effects of high temperatures on human health, productivity, and agricultural production cost an estimated US$16 trillion.
Cumulative 1992–2013 losses from anthropogenic extreme heat likely fall between US$5 trillion and US$29.3 trillion globally,” write the study authors.
The results of this work highlight a major climate justice issue. The study authors found that while economic losses from extreme heat events averaged 1.5% of gross domestic product (GDP) per capita in the world’s richest regions, low-income regions suffer a much greater loss, amounting to 6.7% of GDP per capita.
And that’s not all: the richer regions of Europe and North America – which are among the world’s largest carbon emitters – could theoretically even benefit economically from periods of warmer days.
“We have a situation where the people causing global warming and changes in extreme heat have more resources to be resilient to those changes, and, in some rare cases, could benefit from it,” explains Dartmouth University assistant professor of geography and lead author of the research, Justin Mankin.
As such, the world’s major emitters of CO2 should pay a large part of the costs of adapting to extreme heat events, in addition to providing financial assistance to low-income and highly impacted countries.
Indeed, Justin Mankin goes on to say that, in the context of the global economy, the sharing of costs relating to adaptation measures would benefit wealthy and developing nations alike.
“Our work shows that no place is well adapted to our current climate. The regions with the lowest incomes globally are the ones that suffer most from these extreme heat events.
“As climate change increases the magnitude of extreme heat, it’s a fair expectation that those costs will continue to accumulate,” the researcher concludes.