Global Heat Stress Projected to Cause Hundreds of Thousands of Extra Deaths

A Climate Impact Lab report estimates that extreme heat could cause an additional 430,000 deaths each year by 2050, with the greatest toll falling on low‑income nations that lack reliable electricity and air‑conditioning. The study identifies 18 high‑risk countries—primarily in northern sub‑Saharan Africa (including Niger, Mali, Burkina Faso and Chad) and South Asia (Pakistan, Bangladesh, Nepal, Myanmar)—home to about 676 million people, where roughly 377,000 deaths could occur annually.

A separate study published in *Nature Climate Change* finds that hazardous heat stress has risen worldwide over the past five decades. Around 70 % of the global population now experiences at least 90 days of strong heat stress per year, up from 55 % in the 1970s, with nighttime “feels‑like” temperatures increasing faster than daytime highs. The authors cite a recent European heat wave that caused over 10,000 excess deaths, underscoring that heat is already the deadliest extreme‑weather threat, especially for children, the elderly and those with underlying health conditions. Both reports call for urgent, equitable climate finance and stronger heat‑health action plans.