Heat, Not Floods, May Become Climate Change's Biggest Killer: Report

The biggest ramification of climate change may not be storms or floods but more people dying from heat, with poorer and hottest regions set to suffer the most, a new report has warned.

While cooler areas may see fewer deaths, hotter countries and cities will face rising mortality if no action is taken, according to the Climate Impact Lab Mortality Report.

Cooler regions such as Scandinavia may actually see fewer temperature-related deaths drop by more than 70 per 100,000 people, because winters will be less deadly, while hotter regions such as Northern Africa, the Middle East, and Southwest Asia may see more heat-related deaths.

For example, the Sahel region, including Niger and Burkina Faso, may see an increase of more than 60 deaths per 100,000, 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.

The report states that poorer countries are hit harder because they lack resources to adapt. "Ten times more people are projected to die each year in lower-income countries (about 391,000 people) than in higher-income countries (about 39,000 people) due to shifting temperatures," it mentions.

For example, Djibouti in East Africa is projected to see an increase in temperature-related deaths. It is two times that of the wealthier country of Kuwait in the Middle East, despite their similar climate. 

In Djibouti, temperature-related mortality is projected to increase by 55 deaths per 100,000, on par with the current death rate of HIV/AIDS, while Kuwait is projected to experience 25 additional deaths per 100,000, less than half the current death rate of heart disease. 

Similarly, wealthy cities such as Phoenix and Madrid are expected to see additional heat-related deaths each year, about 600 and 525 deaths, respectively.

But poorer, hotter cities are hit much harder as they could face thousands of additional deaths. Faisalabad in Pakistan alone could see 9,400 additional deaths per year.

Overall, more than 100,000 city residents worldwide could die from rising temperatures, with one in three of these deaths in Pakistani cities.

The report also shows that climate impacts vary within countries. In the US, northern states and the Rocky Mountains could see fewer deaths, while the southern tier faces increases.

In Bolivia, cooler mountainous areas are projected to see fewer deaths, while the warmer lowlands in the southeast could see about 30 additional deaths per 100,000.

"Temperature-related deaths are an inequitable threat to human well-being. Directing adaptation efforts toward the regions and cities highlighted would benefit communities across a wide range of possible climate futures," the report said.