Heat Could Become Climate Change’s Biggest Killer, Report Warns

Heat and mortality

Climate change may cause more deaths from heat than from storms or floods globally, according to the Climate Impact Lab Mortality Report. The report warns that the biggest human toll of warming may come from rising temperatures, with poorer and hotter regions expected to suffer the most if no action is taken.

While some cooler areas may see fewer temperature-related deaths as winters become less deadly, hotter countries and cities are projected to face rising mortality. The report says regions such as Scandinavia could see temperature-related deaths fall by more than 70 per 100,000 people by 2050, while Northern Africa, the Middle East, and Southwest Asia may see significant increases in heat-related deaths.

Hardest-hit regions

The report highlights especially severe impacts in low-income and already hot regions. In the Sahel, including Niger and Burkina Faso, deaths could rise by more than 60 per 100,000 people, a level higher than Africa’s current malaria death rate. In Pakistan, heat could cause an additional 51 deaths per 100,000 people by 2050.

According to the report, poorer countries are projected to be hit much harder because they have fewer resources to adapt. It estimates that about 391,000 people in lower-income countries could die each year due to shifting temperatures, compared with about 39,000 in higher-income countries.

A comparison between Djibouti and Kuwait illustrates that gap. Despite having similar climates, Djibouti is projected to see an increase of 55 temperature-related deaths per 100,000 people, while Kuwait is projected to experience 25 additional deaths per 100,000.

Uneven impact within countries and cities

The report says the effects of rising temperatures will also vary sharply within countries. In the United States, northern states and the Rocky Mountains could see fewer deaths, while the southern tier is expected to see increases. In Bolivia, cooler mountainous areas are projected to see fewer deaths, while the warmer southeastern lowlands could see about 30 additional deaths per 100,000 people.

Cities show similar disparities. Wealthier cities such as Phoenix and Madrid are expected to record about 600 and 525 additional heat-related deaths each year, respectively. But poorer, hotter cities could face much higher totals. Faisalabad in Pakistan alone could see 9,400 additional deaths per year.

Overall, the report projects that more than 100,000 city residents worldwide could die from rising temperatures, with one in three of those deaths occurring in Pakistani cities.

The report concludes that temperature-related deaths are an unequal threat to human well-being and says adaptation efforts should be directed toward the regions and cities most at risk.