Wildfire Disasters Surged in the Past 10 Years, Study Shows

Nearly half of the world's worst wildfire disasters have occurred in just the past decade, new research from UC Merced's Fire Resilience Center shows.

A study published Thursday in the journal Science reveals that 43 percent of catastrophic wildfire disasters struck in the past 10 years. Researchers analyzing 44 years of disaster data found that economic disasters increased more than four times and fatal disasters causing 10 or more deaths tripled since 1980, with particularly sharp increases in recent years.

"The rise in wildfire disasters isn't just a perception, it's reality," said co-author Professor Crystal Kolden, director of the Fire Resilience Center. "For decades, wildfires primarily impacted largely unpopulated areas, but contemporary catastrophic fires are killing more people and destroying more homes and infrastructure."

"We're witnessing a fundamental shift in how wildfires impact society," said lead author Professor Calum Cunningham from the University of Tasmania's Fire Centre.

The study examined wildfire events that killed 10 or more people or ranked among the 200 most economically damaging. This escalation has occurred despite massive increases in firefighting investment. Federal fire suppression spending in the United States increased 3.6-fold to $4.4 billion by 2021, yet disasters continued to accelerate.

"A majority of global fire disasters occurred with hellacious fire weather that overwhelmed fire suppression efforts," said co-author Professor John Abatzaglou, a climatologist at UC Merced. "Moreover, such extreme fire weather conditions are becoming more likely, increasing the odds of disastrous fires. While we have seen this play out in catastrophic fires in California, the same factors have played out across the globe."

Damage peaked catastrophically in 2018 at five times the 44-year average, totalling $28.3 billion globally. Half of all 43 fire events that caused $1 billion or more in damage since 1980 occurred in the last decade alone.

The researchers found disasters occur where three factors converge: intense daily fire activity, populated areas and valuable infrastructure. Mediterranean-type forests found in southern Europe, California, southern Australia and Chile, along with temperate conifer forests in places like western North America, experience disasters at rates far exceeding their land area.

Critically, half of all disasters struck during the most extreme weather conditions on record: the worst 0.1 percent of days that occur only once every few years. These extreme "disaster weather" conditions have become dramatically more common, with severe fire weather increasing more than two-fold, atmospheric dryness increasing 2.4 times, and severe droughts increasing 3.4 times since 1980.

"We're dealing with fires under weather conditions fundamentally more dangerous than previous generations experienced," said co-author Professor David Bowman from the University of Tasmania.

The research team's risk model successfully forecast major disasters that occurred after the study period, including the devastating Los Angeles fires in January 2025, which caused an estimated $65 billion in damages, likely the costliest fire disaster in history. Chile's deadly Las Tablas Fire in 2024, which killed 135 people, also struck in an area the model identified as extremely high risk.

"This provides a roadmap for where the next catastrophic disasters are most likely to occur," Bowman said. "But climate change has fundamentally altered the game. We need to adapt how we live with fire, not just fight it."

The true impact extends far beyond recorded direct losses. While Indonesia's 2015 fires caused $1.2 billion in direct damage, the World Bank estimated total economic costs at $19.9 billion. Smoke from landscape fires kills an estimated 1.5 million people annually worldwide, yet these deaths are absent from disaster databases.

Already, the current fire season has seen activity above normal in both Northern and Southern California, according to Cal Fire. High grass fuel loads and drying conditions, particularly in Southern California, have increased the risk of large fires across various fuel types, including timber and coastal grasses.

The study calls for urgent and comprehensive adaptation strategies that combine Indigenous fire management techniques with modern approaches, including fuel reduction, building standards and evacuation planning.

"The warming climate further exacerbates the risk of fire disasters already escalated through increased population in or near fire-prone areas and fuel accumulation in adjacent lands," Abatzoglou said.

Patty Guerra