Climate change responsible for a third of heat-related deaths

Using empirical heat-related data from 732 cities in 43 countries around the world between 1991 and 2018, the researchers found that 37 percent of heat-related deaths can be directly attributed to human-induced climate change and that increased mortality is evident on every continent.

Scenarios of future climate conditions predict a substantial rise in average temperatures and extreme events and have theorized about their toll on human health. However, so far, no study has evaluated if
and to what extent these effects have already been experienced. 

The researchers examined past weather conditions estimated under scenarios with and without emissions, enabling them to separate global warming and related health impact that are linked with human activity from natural trends.

The impact varies substantially across locations. People living in certain developing countries, which have played a minor part in emissions, are some of the most affected, with the proportion of human-induced, heat-related mortality higher in Central and South America and parts of Asia.

In the United States, the study found that 34.7 percent of all heat-related summer deaths were attributable to human-induced climate change. In Atlanta, 24.3 percent of heat-related summer deaths could be attributed to this cause; on average, around 19 people died in the city each year due to human-induced climate change. 

“This study shows us that the impacts of climate change are already upon us and are being felt all over the world,” says Scovronick. “The southeastern United States is no exception. This work provides another reminder of the need to reduce emissions of greenhouse gases and to implement policies to protect the people most at risk.”