In 2004, wildfires burned an area of Alaska the size of Massachusetts. Researchers feared that the CO2 released by the fires would accelerate climate change and that the destroyed boreal forests would no longer serve as the immense carbon sinks they once did. 

Now, nearly two decades later, scientists have been pleasantly surprised by the fact that the forests are not only regenerating but are on track to hold even more carbon than they did before. 

Before the fires, the boreal forests were largely composed of slow-growing black spruce trees. Since the blaze, there has been room for aspen and birch to move in, varieties that grow more quickly and suck more carbon out of the air as they go. 

Aspen forests are more resistant to fire and over the span of 100 years, come to hold 160 percent more carbon than spruce forests. This regrowth is a silver lining in the cloud of increased forest fires. Boreal fires used to burn every 100 years or so and then regenerate. Now, fires in boreal forests in Canada and Russia are becoming more common, emitting large amounts of carbon as they go. 

Although we must still fight to prevent these fires and the warming climate that increases their frequency, this is a glimmer of hope that boreal forests are more resistant to climate change than we once thought.