Fires Are the Sum of Our Choices

In early February, the deadliest South American wildfires in a century swept through Valparaiso, Chile, killing more than 100 people. It was almost six months to the day since the deadliest American fires in a century killed more than 100 people when flames tore through Lahaina, in Maui, burning up much of Hawaii’s precolonial capital and forcing 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 half a year might 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 the land burned last year in Canada and more than twice as much land as was destroyed in Australia’s Black Summer of 2019-20, 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 a 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 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 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 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.