In brief
A 2026 Lancet Countdown report highlights record heat‑related deaths and widespread energy pollution, calling for climate change to be recognized as a global health emergency. The analysis, involving 146 researchers worldwide, shows a 68‑percent attribution of heat deaths to human‑caused warming and identifies significant economic losses from heat exposure. Despite $2.1 trillion invested in clean energy in 2025, fossil fuels still supply over 80 % of global electricity, producing millions of deaths yearly.
Experts from the Lancet Countdown 2026 report have urged that climate change be declared a global health emergency, a designation that signals an urgent need to prevent widespread disease and suffering worldwide. The call, announced on November 6, 2026 in Sydney, emerged from a comprehensive analysis conducted by 146 researchers across 71 institutions, including seven academics from the University of Sydney.
The report, produced by University College London in strategic collaboration with the World Health Organization, defines a global health emergency as “a condition that threatens the health of a large population and requires an immediate, coordinated response to reduce mortality and morbidity.” It finds that many climate‑driven health hazards accelerated in the decade following the 2015 Paris Agreement, surpassing the pace of increase seen in the preceding ten years.
Heat has become the most lethal climate factor. The study estimates an average of 540,800 deaths per year between 2016 and 2023, with climate change responsible for roughly 68 percent of those fatalities. In 2023, the hottest year during the monitoring period, heat was linked to a record 710,000 deaths worldwide, more than 70 percent of which the report attributes to human‑caused climate change. The analysis also projects that by 2025 heat exposure could cause 573 billion lost work hours and an estimated 1.07 trillion U.S. dollars in lost income.
While clean‑energy investment hit a record $2.1 trillion in 2025, fossil fuels still generate over 80 percent of global electricity. The report warns that pollution from fossil‑fuel combustion is linked to an estimated 2.73 million deaths annually. This figure underscores the persistent health risks from burning coal, oil, and gas, which continue to dominate the energy mix despite growing renewable capacity.
These findings suggest that the health impacts of climate change are now among the largest public health challenges of the century. The Lancet Countdown underscores the urgency of translating policy into action, calling on governments, international organizations, and the private sector to accelerate the transition away from fossil fuels, strengthen heat‑resilient infrastructure, and invest in early warning systems for extreme heat events.
By declaring climate change a global health emergency, experts believe the world can mobilize the same scale of resources and coordination that has historically addressed pandemics and large‑scale epidemics. The Lancet Countdown team emphasizes that such a declaration would signal an international commitment to protect populations from the escalating health risks linked to a warming planet.