A new study maps the relationship between human-caused warming and California’s summer fires over the past five decades.
In the past six years, California has logged three of its five deadliest fires on record, and eight of its 10 biggest. More than 100 people have died, tens of thousands have been displaced, and millions more have been subjected to smoky air, the health consequences of which we don’t fully understand.
We know that climate change supercharges these fires thanks to the drier environments it creates, but by how much is tricky to say. Fire science is a complicated thing: A blaze might arise from a lightning strike, a hot car on tall summer grass, snapped power lines. But a paper published today in Proceedings of the National Academy of Sciences delivers a fuller sense of the relationship between human-caused warming and California’s wildfires. It finds that climate change is responsible for almost all of the increase in scorched acreage during the state’s summer fires over the past 50 years. And its authors predict that the increase in burned area will only continue in the decades to come. The arrival of this study is a timely reminder just days after East Coasters endured a toxic haze that originated in Canada: Wildfire is an international problem, and it’s likely to get worse as time goes on.