The number of people whose lives or property are at risk from wildfires has surged by almost 40% in just two decades, according to new research.
Analysis by an international team of scientists showed that 440 million people were threatened by fire encroaching on their homes between 2002 and 2021.
And while the area affected decreased over the study period, the number of people affected each year rose by 7.7 million.
Structures surrounded by scorched land in the aftermath of a wildfire in Unhais da Serra, Covilha area, Portugal.
Pic: Reuters
Dr Matthew Jones, from the University of East Anglia, told Sky News that a combination of climate change and population movements is driving the increase.
“We’re seeing hotter, drier conditions, and that’s leading to more fire-prone weather,” he said.
“We’re also seeing people migrating more and more into areas that are historically fire-prone. In the western US, we see this idyllic, romantic image of living closer to nature.
“And that’s a trend which is putting people closer to fire-prone landscapes than in the past.”
The researchers analysed 18.6 million records of wildfires over 20 years.
A satellite image shows smoke from wildfires in Piodao, Portugal.
Pic: Maxar/Reuters
High-profile disasters in the US, Europe and Australia grab public attention, but they only account for 2.5% of the global burned area, according to results published in the journal Science.
The vast majority of affected land – 85% – is in Africa. But that is falling as more savannah scrub and grassland is taken over by agriculture – a change so significant that it shows up in global totals, with a 26% fall in land burned over the study period.
“The apparent increase in damaging and destructive wildfire impacts on society has until now seemed perplexing because the area burned by fires globally has been falling,” said Dr Jones.
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He added: “By closely analysing the shifting geography of both fire and population, this study brings vital clarity – our work shows that wildfires really are becoming more frequent and intense in populated areas.
“These changes bring danger to life, damage to property, and threat to livelihood.”
A resident works to extinguish a wildfire approaching Gradiz, in Aguiar da Beira, Portugal, August 14, 2025. REUTERS/Pedro Nunes
The researchers say the increasing vulnerability of human populations to wildfire underlines the urgent need for proactive measures to protect communities.
That could include deliberately starting small, controlled fires to burn off vegetation, so it doesn’t build up.
More public education and engineering solutions are also needed to reduce the number of fires started by people, either accidentally or on purpose.
