Carbon Brief reveals visually just how much the world’s most populous regions have been affected by extreme heat since 2013
Design by Tom Prater
More frequent and intense extreme heat is one of the major impacts of climate change.
As the Intergovernmental Panel on Climate Change’s (IPCC) sixth assessment confirmed, it is “virtually certain” that “there has been increases in the intensity and duration of heatwaves and in the number of heatwave days at the global scale from 1950”.
Extreme heat events can have serious health impacts – Europe’s 2003 summer heatwave, for example, caused more than 70,000 deaths. Extreme heat can also worsen air quality problems and ground-level ozone, exacerbate drought and wildfire risk, reduce labour productivity, damage infrastructure and reduce crop yields.
There are many ways to measure extreme heat. Absolute temperature is one, but a key factor for the impacts of heat extremes is also how much higher temperatures are compared to normal for a specific location.
To assess how the incidence of extreme heat has changed over time, Carbon Brief has examined which regions experienced all-time daily heat records in each year since 1950.
The analysis shows that the number of people experiencing all-time high heat events has increased dramatically over the past three decades. Overall, about half the world’s population is living in regions that saw their hottest daily temperatures since 1950 during the past 10 years.
In 2022 alone – which was the fifth or sixth warmest year on record for the Earth’s surface as a whole across different datasets – approximately 380 million people saw their hottest single hourly temperature ever recorded.