Overview
- Climate Impact Lab’s interactive El Niño Heat Mortality Tracker, run by researchers linked to the University of Chicago, now estimates roughly 373,000 extra heat-related deaths between October 2026 and March 2027.
- The tracker combines observed daily temperatures, historical temperature–mortality links and 51 ECMWF seasonal forecast simulations to produce probabilistic, monthly-updated estimates rather than confirmed individual counts.
- The updated forecast raised the accumulated June 2026–March 2027 estimate to about 857,400 deaths after the team extended the horizon to March and replaced earlier projections with much hotter-than-expected August and September observations.
- Projected impacts are highly concentrated: country-level October–March figures put Nigeria (~56,000), India (~55,200), Indonesia (~29,300), Brazil (~19,500) and Sudan (~14,700) among the worst hit, reflecting population size, baseline climate and limited cooling and health capacity.
- Researchers say the tracker is meant to guide public-health preparedness—such as early warnings, cooling centers, water supply and expanded care—but the numbers carry large uncertainty and will be revised with monthly updates as new observations and forecasts arrive.