Subtract out the conspiracists and the willfully ignorant and the argument marshaled by skeptics against global warming, roughly restated, assumes that scientists vastly overstate the consequences of pumping greenhouse gases into Earth’s atmosphere. Uncertainties in their calculations, the skeptics say, make it impossible to determine with confidence how bad the future was going to be. The sour irony of that muttonheaded resistance to data is that, after four decades of being wrong, those people are almost right.

As of July 31, more than 25,000 firefighters are committed to 140 wildfires across the United States—over a million acres aflame. Eight people are dead in California, tens of thousands evacuated, smoke and pyroclastic clouds are visible from space. And all any fire scientist knows for sure is, it only gets worse from here. How much worse? Where? For whom? Experience can’t tell them. The scientists actually are uncertain.

Scientists who help policymakers plan for the future used to make an assumption. They called it stationarity, and the idea was that the extremes of environmental systems—rainfall, river levels, hurricane strength, wildfire damage—obeyed prior constraints. The past was prologue. Climate change has turned that assumption to ash. The fires burning across the western United States (and in Europe) prove that “stationarity is dead,” as a team of researchers (controversially) wrote in the journal Science a decade ago. They were talking about water; now it’s true for fire.

“We can no longer use the observed past as a guide. There’s no stable system that generates a measurable probability of events to use the past record to plan for the future,” says LeRoy Westerling, a management professor who studies wildfires at UC Merced. “Now we have to use physics and complex interactions to project how things could change.”

Wildfires were always part of a complex system. Climate change—carbon dioxide and other greenhouse gases raising the overall temperature of the planet—added to the complexity. The implications of that will play out for millennia. “On top of that is interaction between the climate system, the ecosystem, and how we manage our land use,” Westerling says. “That intersection is very complex, and even more difficult to predict. When I say there’s no new normal, I mean it. The climate will be changing with probably an accelerating pace for the rest of the lives of everyone who is alive today.”

That’s not to say there’s nothing more to learn or do. To the contrary, more data on fire behavior will help researchers build models of what might happen. They'll look at how best to handle “fuel management,” or the removal of flammable plant matter desiccated by climate change-powered heat waves and drought. More research will help with how to build less flammable buildings, and to identify places where buildings maybe shouldn’t be in the first place. Of course, that all presumes policymakers will listen and act. They haven’t yet. “People talk about ‘resilience,’ they talk about ‘hardening,’” Westerling says. “But we’ve been talking about climate change and risks like wildfire for decades now and haven’t made a whole lot of headway outside of the scientific and management communities.”