As the narrative of the Southern California wildfires has shifted to identifying the causes behind what could prove to be the most expensive natural disaster in U.S. history, a common refrain has emerged on social media that seeks to dismiss the role scientists say climate change played.

Climate change didn’t start the wildfires that are ravaging Los Angeles County this week. But the big swings in weather patterns that have accelerated over the past two decades serve as rocket fuel that intensifies the flames and spreads the devastation.

Extreme weather events — deadly heat waves, floods, fires and hurricanes — are the consequences of a warming planet, scientists say.