But authors of a new study warn that as the climate becomes hotter and drier, future fires could be far more damaging.

They project that the amount of forest burned could double by 2050 and consume 16 percent of the rainforest -- an area nearly the size of the entire state of Michigan, according to Paulo Brando, a professor at the University of California-Irvine and a lead author of the study.

When the rainforest is healthy, its trees and plants pull billions of tons of heat-trapping carbon dioxide from the atmosphere each year, and it is one of the planet's best defenses against climate change.

But fires could imperil its ability to fight climate change, the study found, to the point that the forest actually could begin contributing more planet-warming gases to the air than it absorbs by 2050 -- or sooner.

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