Kristina Dahl

Whose responsibility is a wildfire? It is a kind of existential koan for fire scientists, given how many factors contribute. But this May, as off-the-charts Canadian fires burned, the Union of Concerned Scientists’ Kristina Dahl and her colleagues offered a spellbinding accounting: carbon emissions from the world’s largest fossil-fuel companies and cement makers were responsible for 37% of recent wildfire activity in the North American West. It was only the latest remarkable work from one of the great geographers of our disorienting new world.

Those worrying most over climate have long lamented that its impacts are too diffuse to appreciate and too distant in the future to really motivate people. In recent years, the weather itself has rewritten those rules. But so has Dahl’s work: on extreme heat, sea-level rise, and the evacuation complications of compound disasters. These days, even the most informed among us can feel like they are navigating a terrifying future without a map. Dahl provides one. And then another, and then another.

Wallace-Wells is a journalist and author of The Uninhabitable Earth

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