Viewpoint: As Wildfires Burn, Assigning Blame Is Complicated

With wildfires still raging through parts of California, one question has continued to spark debate: Is climate change to blame?

President Trump, for his part, has taken the stance that he doesn’t “think science knows,” despite extensive evidence linking climate change to the hot and dry conditions that paved the way for the fires. When challenged on this stance in the first presidential debate, he pointed solely to forest mismanagement as the fires’ culprit.

While misinformed, Trump’s errors are instructive: They highlight a recurring problem with the way we talk about the connection between climate science and environmental disaster.

First, Trump’s take reflects the false choice — that either climate change or poor governance is to blame for this disaster — that has caused tension in much recent discussion of extreme weather. Not only are these two factors not mutually exclusive, but they almost always share responsibility for these tragedies’ scales. Second, this false choice underscores a key distinction: There is a difference between the scientific act of modeling climate change’s influence on individual weather events, known as attribution, and the moral and political act of ascribing blame and responsibility. Conflating attribution and blame can distract from important questions about the responsible stewardship of natural resources — questions that are becoming increasingly urgent as climate change takes its toll.

While for decades there has been scientific consensus that the climate is changing, only in the past few years has it become possible for scientists to link that change to particular weather events. Even as it advances, however, attribution science, also called probabilistic extreme event attribution, has uncertainties built into it. Broadly speaking, it’s done by comparing two computer models — one that reflects the world as it is, and another that reflects the world as it would have been without global warming — to determine whether the probability of a weather event was affected by climate change and, if so, by how much.

But the results come with caveats. For instance, attribution science doesn’t determine whether climate change made an event possible, but rather if it made the event more likely. The method is also difficult to apply in locales that have little historical data on weather patterns. And certain kinds of events — hurricanes and droughts, for instance — are harder to model than others. Hard evidence of climate change’s influence on Hurricane Sandy, which battered the northeastern U.S. in 2012, didn’t come until years after the fact.

But for wildfires like the ones currently burning in the West, the links with climate change are relatively easy to model and affirm. Although attribution scientists have yet to publish a formal empirical analysis of this year’s wildfire season, the connections between climate change and wildfires are well-established.

The problem is that the simple scientific question — Did climate change increase the likelihood of the fires in California? — is, in practice, bound up with a much bigger political question: Should our governments be reining in our greenhouse