Climate / Other
Lancet Countdown report links heat to record 710,000 deaths in 2023
The 2026 Lancet Countdown on Health and Climate Change found many climate-related health risks grew faster in the decade after the Paris Agreement.
Source-checked story: attributed primary-source and published reporting; no on-location reporting.
Heat was linked to a record 710,000 deaths globally in 2023, according to the 2026 Report of the Lancet Countdown on Health and Climate Change, the University of Sydney said Nov. 6. More than 70 percent of that toll was attributable to human-caused climate change, the report found.
The 10th annual indicator report represents the work of 146 researchers from 71 institutions and monitors 54 indicators, according to the university. It was led by University College London in strategic collaboration with the World Health Organization.
Heat exposure resulted in an estimated 573 billion potential work hours lost in 2025 and US$1.07 trillion in potential income losses, the report found. Extreme drought affected 51.8 percent of the world’s land for at least one month in 2025, the second highest level recorded.
“The evidence is now unequivocal that climate change is harming health in every region of the world,” said Professor Ollie Jay, director of the University of Sydney Heat and Health Research Centre and chair of the report’s Working Group 1.
Global clean energy investment reached a record US$2.1 trillion in 2025, 82 percent more than the US$1.6 trillion invested in fossil fuels, according to the report, though it found progress remains too slow and uneven to offset mounting harms.
What we know / what we don't
What we know
- The 2026 Lancet Countdown on Health and Climate Change found many climate-related health risks grew faster in the decade after the Paris Agreement.
What we don't know
The source record