Study links tropical deforestation to 28,000 heat-related deaths annually

Tropical deforestation is fueling deadly local warming, contributing to an estimated 28,000 heat-related deaths each year across the globe’s hottest regions, according to new research published Wednesday.

The study, published in the journal Nature Climate Change, examined forest loss between 2001 and 2020 and found that deforestation exposed 345 million people to hotter conditions. Satellite data showed that areas where trees were cleared experienced population-weighted daytime land surface warming of 0.27 degrees Celsius.

“Deforestation-induced local warming is associated with 28,000 heat-related deaths per year,” the authors wrote, estimating a 95% confidence interval of between 23,610 and 33,560 fatalities.

The research found the health burden was highest in Southeast Asia, with 8 to 11 deaths for every 100,000 people living in deforested areas, followed by tropical regions of Africa and the Americas. In some regions, local warming from forest loss accounted for more than one-third of all climate-related heat mortality.

The study said this highlights “the important contribution of tropical deforestation to ongoing warming and heat-related health risks within the context of climate change.”

Previous research has documented links between forest loss and rising surface temperatures, but the authors said little was known about the direct impact on mortality at a global scale.

The findings suggest that forest conservation is not only critical for biodiversity and carbon storage, but also for protecting vulnerable populations from deadly heat.

“Across the tropics, local warming from deforestation was associated with losses in safe thermal working conditions for millions of outdoor workers,” the authors noted, warning that deforestation-driven heat exposure can reduce labor productivity, impair cognitive performance, and increase poverty in low-income countries with limited capacity to adapt.