The number of people dying from the heatwave is likely to increase dramatically in some parts of the world over 60 years by 2080 if policy makers fail to take mitigating measures and adopt effective policies in the health sector, according to research results released today.

Deaths from excessive heat could record a steep rise in tropical and subtropical regions, according to the study, followed by Australia, Europe and the United States. This first global study published in the journal PLOS Medicine aims to help decision makers in planning adaptation and mitigation strategies for climate change.

Antonio Gasparini, associate professor from the London School of Hygiene & Tropical Medicine and the paper’s co-author, said since the turn of the century, heatwaves have been responsible for tens of thousands of deaths, including regions of Europe and Russia.

“This research, the largest epidemiological study on the projected impacts of heatwaves under global warming, suggests it could dramatically increase heatwave-related mortality, especially in highly-populated tropical and sub-tropical countries,” said Gasparrini. “The good news is that if we mitigate greenhouse gas emissions under scenarios that comply with the Paris Agreement, then the projected impact will be much reduced,” said Gasparrini.

The mathematical model the researchers used, implemented different scenarios, including various gas emission ratings, readiness grades and adaptation strategies as well as population density, to estimate the number of heat-related deaths in 412 communities in 20 countries from 2031 to 2080.

The results show that compared to the period 1971 to 2020 and based on an extreme scenario, the Philippines will record 12 times more heat-related deaths in the period 2031-2080. Based on the same scenario, Australia and the United States could face five-fold deaths while Britain is likely to record four times more deaths resulting from heatwaves during the same period. Based on a less extreme scenario, research predicts that Britain will record about two-fold deaths from heatwaves in the period 2031-2080.

Scientists, however, note that their research has some limitations, as it can only show relatively simple assumptions about how countries can or cannot adopt climate policies. The findings should therefore be interpreted as potential impacts based on hypothetical scenarios and not as predictions of the future.