Overview
- The Climate Impact Lab released the projection on Wednesday that an unusually strong El Niño could produce roughly 451,000 additional heat-related deaths worldwide from June 2026 through February 2027.
- Researchers derived the estimate by applying temperature–mortality relationships from 24,378 regions to seasonal forecasts and a 1996–2025 baseline, and they project near-term land temperatures about 1.2°C above normal with roughly 44% more extremely hot days.
- The burden is unequal with the Sahel hardest hit—about 66,800 extra deaths projected from September to February and roughly 31,400 of those in Nigeria—while Indonesia, India, parts of Southeast Asia and Brazil also face large increases.
- The analysis covers heat-only mortality and has not yet undergone independent peer review, and the lab says it will publish detailed methods and update projections as El Niño evolves.
- Researchers urged immediate measures such as heat warnings, cooling centres, hydration points and protections for outdoor workers because targeted responses can prevent many of the projected deaths.