The study used satellite data on tree cover loss together with temperature and mortality models to assess how deforestation altered local climate and human health between 2001 and 2020. By linking tree loss to changes in local temperature and to mortality estimates, the researchers measured the human cost of removing forest cover.
The analysis reports that 345 million people were exposed to localized warming directly linked to deforestation in that period, and it estimates about 28,000 heat-related deaths per year, concentrated mainly in Africa, Southeast Asia and Latin America. Regionally, 67 million people were exposed in Latin America, 148 million in Africa and 122 million in Southeast Asia.
Regional data show large deforested areas: around 760,000 km2 in Latin America, 490,000 km2 in Southeast Asia and 340,000 km2 in Africa. Local temperature increases were highest in Latin America (0.53°C), followed by Africa (0.39°C) and Southeast Asia (0.37°C). The authors note that forest loss accounts for nearly 70 per cent of observed warming in deforested parts of Latin America, and the strongest warming aligns with major loss zones such as the Arc of Deforestation and the islands of Sumatra and Kalimantan.
Independent experts emphasised that smaller exposed populations do not mean low risk, because many rural and indigenous communities face social and health deprivations that increase vulnerability. Governments have pledged to halt forest loss by 2030, but gaps in monitoring remain. Researchers urge faster action: halt deforestation, expand protected forests, support local communities with adaptation measures, and explicitly include health impacts in climate and land-use planning to slow local warming and save lives.
Difficult words
- deforestation — loss of forests and tree cover
- mortality — number of deaths in a population
- localized — limited to a small specific area
- expose — to make someone face a risk or dangerexposed
- concentrate — to be present in large numbers in one placeconcentrated
- pledge — formally promise to do somethingpledged
- vulnerability — state of being more likely to be harmed
- adaptation — changes to reduce harm from a threat
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- How might local health systems respond to increased heat-related deaths in rural and indigenous communities? Give reasons from the article.
- What challenges could governments face in meeting their pledge to halt forest loss by 2030, based on the article?
- How would including health impacts in climate and land-use planning change actions to protect forests and people?
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