New Delhi: Climate change worsened the Los Angeles wildfires and made it 35% more likely than they would have been in conditions without human-caused warming, according to a new analysis by 32 climate scientists as part of World Weather Attribution.
“The hot, dry, and windy conditions that drove the fires were about 35% more likely due to warming caused primarily by the burning of oil, gas, and coal,” the analysis said. It also projected that these fire-prone conditions will become a further 35% more likely if warming reaches 2.6°C, which is expected by the end of the century.
The findings are significant in light of President Donald Trump’s executive orders to revoke all climate policies and the US’s withdrawal from the Paris Agreement.
Low rainfall from October to December is now about 2.4 times more likely compared to the pre-industrial climate. Fire-prone conditions have extended by about 23 extra days each year, increasing the chance that a fire will start during peak Santa Ana winds.
“Climate change increased the risk of the devastating LA wildfires. Drought conditions are more frequently pushing into winter, increasing the chance a fire will break out during strong Santa Ana winds that can turn small ignitions into deadly infernos. Without a faster transition away from planet-heating fossil fuels, California will continue to get hotter, drier, and more flammable,” said Clair Barnes, World Weather Attribution researcher at the Centre for Environmental Policy, Imperial College London, in a statement.
“This was a perfect storm of climate-enabled and weather-driven fires impacting the built environment. While southern California is no stranger to high-impact wildfires, the impact of these fires and the timing of these fires in the core of what should be the wet season differentiate this event as an extreme outlier,” said John Abatzoglou, professor of climatology at the University of California, Merced, in a statement.
The recent wildfires was the most destructive in LA’s history and potentially the costliest in US history, researchers said.
Although the damages have yet to be fully assessed, the fires resulted in large-scale human health impacts, including 28 deaths, along with widespread property and commercial losses, including 10,000 homes. The reconstruction of burned areas will incur significant costs, with private insured losses estimated at $27.2 billion. AccuWeather estimated total losses to be greater than $250 billion, the analysis said.
Researchers also found that the LA wildfire season is becoming “longer and more dangerous as fossil fuel emissions heat the climate.”
“Highly flammable drought conditions now last about 23 more days each year on average than in the pre-industrial climate, an analysis of historical weather data found. Due to highly variable rainfall, drought conditions can last much longer in some years,” they said.
Hotter air temperatures are evaporating more moisture from plants, making them easier to burn. Drier, flammable conditions persisting later in the year increase the chance a wildfire will break out during the peak of the Santa Ana winds in December and January, they added.
The team used two multi-model ensembles from climate modelling experiments: Sea Surface Temperature (SST)-driven global circulation high-resolution models and regional climate models.
If countries continue on their current emissions trajectory, it would lead to 3.1°C warming over pre-industrial levels, according to the Emissions Gap Report 2024.
HT reported on January 21 that Trump signed an executive order soon after taking office directing the US’s withdrawal from the Paris climate agreement.
The US submitted its updated NDC (nationally determined contribution) in November under the outgoing Joe Biden administration, promising a 61-66% reduction in greenhouse gas emissions below 2005 levels by 2035.
The White House stated that the NDC was achievable even if Trump took charge, through the Inflation Reduction Act and state-level policies. However, the NDC announcement is no longer available on the White House website.
Since November 1, four countries have submitted NDCs for the 2035 period, including the UAE, Brazil, the US, and Uruguay. All countries are expected to submit new climate targets by February to align with the emissions reductions necessary for limiting global temperature rise to 1.5°C over pre-industrial levels.