Two recent studies indicate that human-caused climate change significantly increased the likelihood of extreme fire weather conditions that fueled devastating wildfires in Spain and France this past week. The analysis, conducted by World Weather Attribution, found that climate change made the hot and dry conditions responsible for Spain's record inferno 20 times more probable and doubled the chances of extreme fire conditions for the flames in France.
Over the past 26 years, warming temperatures have tripled the odds of severe fire risk conditions in Spain and increased those chances by 40% in France, according to the World Weather Attribution report. Scientists factored in air temperature, drought, humidity, and wind to assess the weather patterns contributing to the fires.
Friederike Otto, a climate scientist at Imperial College of London and coordinator for World Weather Attribution, stated that the change in fire weather conditions in Spain is "extremely strong" and one of the most significant changes she has observed. Spain is experiencing its hottest summer on record, following a wet January that promoted plant growth before a severe drought, creating an abundance of wildfire fuel. The report also cited land abandonment in Spain, leading to unmanaged vegetation drying out, as an additional contributing factor.
A separate study, published in the journal Scientific Reports, found that the number of days with extreme fire weather in Southern Europe has more than doubled compared to previous decades. In earlier periods, there were approximately 10 such days annually; this number has now risen to around 25 days per year. Furthermore, these extreme fire weather days are about 50% more intense than they were between 1981 and 2010, according to study author Raúl Cordero, a climate scientist at the University of Groningen.
Cordero noted that while fire suppression and management techniques had reduced the number of fires and land burned in Southern Europe from the 1980s to 2018, climate change has now overwhelmed these improvements. "It doesn’t matter how many resources or how much money you have, you just cannot stop the propagation of a fire when the weather is so extreme," Cordero said.
While the World Weather Attribution study was conducted rapidly and has not yet undergone peer review, Otto and her colleagues utilized scientifically accepted techniques. Their reports are often published in peer-reviewed journals retrospectively. The team calculated the increased likelihood of such fire intensity by comparing current fire weather severity to past measurements and to hypothetical conditions if the world were 1.4 degrees Celsius cooler, reflecting the approximate global warming since pre-industrial times.
Fire scientists not involved in the studies, such as Jacob Bendix from Syracuse University and John Abatzaglou from the University of California Merced, affirmed the findings. Bendix stated that the research confirms the long-held understanding that fires ignite more easily and spread faster under extreme heat and drought, conditions that have become more common due to anthropogenic climate change. Abatzaglou commented that these findings clearly demonstrate climate change is an immediate reality, not a future problem.
Otto emphasized the need to cease burning fossil fuels, warning that continued reliance on them will lead to further global temperature increases and worsening fire weather conditions, potentially exceeding humanity's capacity to adapt.