LA fires were larger and more intense because of planet-warming pollution, study suggests
The devastating wildfires that have swept through Los Angeles over the past week were amplified in size and intensity by climate change, according to a recent analysis by researchers at the University of California, Los Angeles (UCLA). While the fires likely would have occurred regardless, the study concludes that global warming-driven factors significantly worsened their impact.
The research estimates that approximately 25% of the vegetation fueling these fires can be attributed to climate change. The report emphasizes that while the fires would have ignited in a world without human-induced climate pollution, they would have been “somewhat smaller and less intense.” This raises critical questions about whether these fires might have been more manageable in the absence of climate change’s fire-exacerbating effects.
Fires Fueled by Climate-Driven Factors
Since January 7, twelve major fires have erupted across the Los Angeles region, coinciding with an extraordinary Santa Ana wind event. The blazes have burned over 60 square miles, destroyed more than 12,000 structures—including homes, businesses, and outbuildings—and left lasting scars on the landscape. Among them, the Eaton and Palisades fires have become the first and second-most destructive wildfires in Southern California’s recorded history, as classified by CalFire.
Several climate-related factors played a role in amplifying the fires’ severity. Southern California experienced two consecutive winters of exceptionally high rainfall, with downtown Los Angeles recording double the average precipitation. This led to an abundance of grasses and shrubs, providing ample fuel for fires when conditions turned dry.
Last summer’s abnormally warm temperatures and the severely delayed rainy season further dried out the vegetation. Between May 2024 and early January 2025, Los Angeles saw just 0.29 inches of rain, marking its second-driest period on record since 1877. By the time the fires ignited, vegetation moisture levels ranked among the lowest ever recorded.
“Weather Whiplash” and Its Consequences
These dramatic shifts between wet and dry conditions, described by researchers as “weather whiplash,” are becoming increasingly common as global temperatures rise. Wet years encourage the growth of vegetation, while subsequent dry periods leave it highly flammable. This cycle magnifies the risk and intensity of wildfires and other natural disasters like flash floods.
The report also examined the unusual strength of the Santa Ana winds, which played a significant role in spreading the flames. While the event was classified as extreme, the researchers found no direct link between climate change and stronger Santa Ana winds.
Preparing for a Hotter, Drier Future
The study underscores the urgency of adapting to a warming planet where larger, more destructive fires are expected to become the norm. It recommends prioritizing aggressive wildfire suppression during periods of heightened risk, designing homes to be more fire-resistant, and reconsidering urban development in high-risk areas.
Los Angeles typically sees its heaviest rainfall in January and February, but this year’s forecast paints a grim picture, with January expected to remain dry and below-average precipitation likely extending into February.
As the planet continues to warm, the cycle of wet and dry extremes poses an escalating threat to regions like Southern California, leaving policymakers and communities to grapple with the challenge of mitigating wildfire risks in an uncertain future.