Extreme heat kills 540,000 people a year, Lancet report finds
The Lancet Countdown on Health and Climate Change, a yearly review by almost 150 researchers, says heat deaths have risen sharply in the ten years since the Paris Agreement.
Extreme heat causes an average of 540,000 deaths a year, according to a new edition of the Lancet Countdown on Health and Climate Change, published on Wednesday. Almost 150 researchers from more than 30 countries worked on the report. They say the number of heat deaths has risen sharply in the ten years since the Paris Agreement.
Average heat-related deaths rose by about 36% in a decade. Between 2016 and 2023 they averaged 540,800 a year. In 2023, the last year with enough data, about 710,000 people died from heat, the report says. The World Health Organization (WHO) says 630,000 people died of HIV and 597,000 of malaria that year.
Heat killed more people in 2023 than HIV or malaria
Deaths
Heat killed more people in 2023 than HIV or malaria (deaths). Highest: Heat, 710,000; lowest: Malaria, 597,000; 3 items. Source: Lancet Countdown (heat); WHO (HIV, malaria).
View data
| Item | Deaths |
|---|---|
| Heat | 710,000 |
| HIV | 630,000 |
| Malaria | 597,000 |
The researchers say climate change should be officially declared a global health crisis.
Climate change can also speed up the spread of infectious diseases. The West Nile virus is spreading more easily in Europe and is probably here to stay in the Netherlands too.
The report also has better news. Clean energy is cutting deaths from air pollution, and deaths from indoor air pollution have fallen too.
WHO director-general Tedros Adhanom Ghebreyesus said: "The evidence is undeniable: climate change is one of the biggest threats to human health." The researchers urge a rapid cut in fossil fuel extraction and greenhouse gas emissions.
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Lancet Countdown on Health and Climate Change
The Lancet Countdown on Health and Climate Change is an international collaboration of researchers that publishes an annual report, in the medical journal The Lancet, tracking how climate change affects human health. Each edition measures indicators such as heat-related deaths, disease spread, and health effects of air pollution, and assesses how countries are responding. Its findings are widely cited by governments, health organisations and the media when discussing the health risks of climate change.
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