The return of the “urban firestorm” could have been avoided. Now it can’t.
Ibrahim Rayintakath
It has been a year of fire extremes
In early February, the deadliest South American wildfires in a century swept through Valparaiso, Chile, killing more than a hundred people. It was almost six months to the day since the deadliest American fires in a century killed a hundred people when flames tore through Lahaina, in Maui, burning up much of Hawaii’s precolonial capital and forcing local residents to jump into the ocean for safety, the flames leaping over them to ignite the boats docked in the harbor.
Two record-setting episodes of fire death in the span of one half year may once have looked like a world-historical ecological coincidence, but it has been a year of fire extremes — and a year in which the world has mostly whistled past them. In the United States, mercifully little land burned — only 2.6 million acres, which was less than half the recent average. But in Canada, fires ate through more than twice as much forest as the country’s previous modern record, the total burn scar large enough that more than half the world’s countries could fit inside. In Greece, one fire forced the country’s largest-ever evacuation, and another became the largest fire in the history of the European Union. And in Australia, the bush fire season has burned over 150 million acres — three times more land than burned last year in Canada, and more than twice as much land as was destroyed in Australia’s “Black Summer” of 2019-2020, when Sydney Harbor was so choked with smoke that ferries couldn’t navigate the waters, at least a billion animals were consumed by flames, and panicked evacuees had to be rescued from the beach by military helicopter.
When the fire historian Stephen Pyne says that we are now living in the “pyrocene,” this is part of what he means: Forest fires are now burning twice as much tree cover, globally, as they did just 20 years ago, and the world is quickly inuring itself to that fact. In parts of the world as far-flung as Fort McMurray, Alberta; Lahaina, Hawaii; Boulder County, Colo.; and now Valparaiso, Chile — where at least 15,000 homes have been destroyed — the new age of fire has produced what the climate scientist Daniel Swain has called the return of the “urban firestorm.” Of the 10 deadliest fires anywhere on earth since 1900, five have occurred since 2018.
How did it get this way? The intuitive, conventional answer is climate change. But where people choose to live matters, too. And in the United States, especially, you increasingly hear a somewhat contrarian explanation that emphasizes fire suppression rather than warming.
That just-so story goes something like this: Beginning in the early 20th century, motivated particularly by horrific and deadly fires, Americans began a broad effort to suppress them by snuffing out any nascent blaze — no matter how remote or nonthreatening. They were so successful that over the course of many decades, the landscape accumulated an enormous amount of excess dry forest, which would have long since burned in the absence of human intervention. Instead, it was poised to burn much more spectacularly whenever it found a spark. Warming is exacerbating those base line conditions, the story goes, but the base line was set by fire suppression, forest management and the tremendous expansion of human settlement into what is called the “wildland-urban interface” — which both necessitated further fire suppression and helped bring many more people much closer to the risk of fire.
In its broad strokes, this story is true. For about a half century, fires were actively suppressed in the American wilderness, with one result being that there was, at the end of those decades, much more of what fire scientists coolly call “fuel.”
What that tells us about the meaning and the future of the pyrocene is a bit less clear. The forest-management story has been offered as a corrective to climate-focused wildfire alarm, and it is, in its way, hopeful: If forest policy is to blame for the terrifying risk of out-of-control fire, in theory forest policy should allow us to bring it under control, too, without requiring that we get a handle on global warming first.
But the hopeful story is also at least somewhat incomplete, particularly at the global level. Wildfires have raged out of control in places such as Australia and Canada and Siberia and Chile that haven’t used the same fire suppression doctrine as the United States did.
Every fire ecosystem has its own ecology and idiosyncratic causal map: how the density and character of regional forests has changed over time, both from human and natural influence; the work of the local timber industry and the pattern of residential development; shifting weather patterns and the behavior and responsibility of power companies and campers and arsonists, as well.
But there are also simpler and more universal ways of thinking of conceptualizing the risk. The fire scientist Mike Flannigan describes it straightforwardly as a matter of fuel load, ignition and fire weather. It’s mainly the last factor that varies much year to year, he says, or even decade to decade — and helps explain why, for instance, 200 times as much land burned in British Columbia last year as did in 2020. That isn’t because there were 200 times as many trees around to burn all of a sudden.
Even in the American context, the fire suppression story may be too simplistic. For one thing, the conventional estimates for 20th-century fire suppression are fairly crude and don’t take into account how human construction has reduced the amount of forested land that could burn. And recent research has suggested that the increase in area burned in California in recent decades is almost entirely attributable to anthropogenic climate change, though the researchers also caution that the increase has been observed against background conditions created by fire suppression.
It’s all a bit complicated. Put a hundred climate scientists and forest ecologists in a bar, the climate scientist John Abatzoglou and the forest ecologist Solomon Dobrowski tell me, and it’s a good bet they’ll all agree with a statement like “more heat, less moisture, more human-caused ignitions and more fuel have dramatically increased fire activity in the Western U.S. and beyond.” But ask the 100 scientists about the relative contributions from forest management and climate change, they say, and consensus collapses: The climate scientists might suggest that climate change contributes something close to two-thirds of our current fire predicament, while the ecologists might flip the estimate — two-thirds from forest management and one-third climate factors.
In other words, this isn’t an either-or set; it’s both-and. But that complexity is often maddeningly difficult to internalize.
This tension extends past wildfire. On one hand, there’s been a tendency among climate-conscious liberals to pin a vast array of social ills on global warming, sometimes downplaying other causes — a tendency that Mike Hulme, a Cambridge professor of geography, has called “climatism.” This critique is important: We can’t really talk about hurricane vulnerability, for instance, in isolation from coastal development, early-warning systems, local building codes and insurance policies.
But the inverse is also true: We can’t pretend that, if climate change is only one factor in determining overall risk and human hazard, we should therefore treat the growing threat from warming as irrelevant or trivial. It surely would have been wiser not to have built so many California homes — nearly half of all those built in the state between 1990 and 2010 — in areas of high and growing wildfire risk, but saying so doesn’t diminish the risk millions of Californians now face. Perhaps the controlled burning of a few million acres annually in the American West can offset the impact of global warming on wildfire in the decades ahead. That doesn’t mean warming doesn’t matter; in fact, it is one way of quantifying the cost.
And while is certainly wise to reintroduce some more fire to the landscape — to cultivate more of what Pyne calls “good fire,” in part to forestall future “bad fire” — the scale of that job is somewhat staggering, given the rate of human development across the west: According to some estimates, 20 million acres in California need to burn for its forest to re-equilibrate, a land mass of nearly one-fifth of the state.
In Chile, too, there are patterns of development and forest policy that might’ve prevented the loss of those hundred lives and those 15,000 homes. But one of the challenges of climate change, even in the present tense, is that none of us are living in those counterfactual histories. Instead, we’re living in a timeline in which large gaps have opened up between the climate we anticipated and the one we are now confronted with, between the infrastructure we built on the basis of those expectations and the world we might’ve engineered, and between the standards for safety and preparedness we once had and the ones we are now revising and haphazardly improvising in the face of rising threats.