(Paris) Climate change has caused an average of 26 more days of extreme heat across the world over the past twelve months, according to a report from the climate center of the International Federation of Red Cross and Red Crescent Societies ( IFRC) unveiled on Tuesday.
To determine the number of “excess” heatwave days due to humanity’s greenhouse gas emissions, the report, established with the scientific network World Weather Attribution (WWA) and the NGO Climate Central, counted, between May 15, 2023 and May 15, 2024, the days where regions experienced temperatures higher than 90% of those recorded over the period 1991-2020.
The scientists then analyzed, using a method validated by their peers, the influence of climate change on each of these excessively hot days.
They concluded that on average worldwide, 26 of these days recorded extreme temperature made twice as likely by the effect of global warming, allowing them to classify them as an “excess” heat day.
Furthermore, the vast majority of the world’s population has suffered heatwaves, since 6.3 billion people, or approximately 78% of humanity, experienced at least 31 days of extreme heat over the past year.
In total, 76 extreme heat waves were recorded in 90 different countries, on every continent except Antarctica, scientists estimate.
The five most affected countries are all in Latin America: Suriname experienced 182 days of extreme heat compared to 24 estimated in the absence of climate change, Ecuador (180 days instead of 10), Guyana (174 compared to 33 ), El Salvador (163 against 15), and Panama (149 instead of 12).
“Floods and hurricanes may grab the headlines, but the effects of extreme heat are just as deadly,” Jagan Chapagain, secretary general of the IFRC, said in a statement.
“It is known that tens of thousands of people have died due to extreme heat over the last 12 months, but the true toll is probably in the hundreds of thousands or millions,” estimates the organization, because heatwaves “ exacerbate previous health problems.
In Europe, a reference study attributed the deaths of 61,672 people to heatwaves in the summer of 2022.
Extreme heat “is wreaking havoc on human health, critical infrastructure, the economy, agriculture and the environment,” said Aditya V. Bahadur, director of the IFRC climate center, who advocates for strengthening emergency services, better organization of urban space or even improving the safety of workers around the world.
“The heat kills, but it is not inevitable. There are many solutions, some of which are inexpensive or inexpensive,” also argued climatologist Friederike Otto, member of the WWA, during the presentation of the report at the UN in Geneva.
“It is imperative to act at the level of the community, the city, the region and the country,” she insisted, pleading in particular for cities to develop and implement action plans to anticipate heat waves.
On a larger scale, Friederike Otto also proposes integrating air conditioning needs into social protection programs and an update of building regulations to encourage the construction of more suitable housing.