Tropical forests have emerged as a crucial factor in the fight against climate change, according to a new NASA-led study published Friday which finds that they are absorbing carbon dioxide at a far higher rate than previously thought.

As atmospheric levels of greenhouse gases have continued to rise, tropical forests, like those found in Malaysia, have been absorbing roughly 1.4 billion metric tons of carbon dioxide out of a total global absorption of 2.5 billion, NASA found. Those rates are not only higher than previously estimated, they are also higher than those of the vast boreal forests found in northern regions like Canada and Siberia—which are diminishing.

“This is good news, because uptake in boreal forests is already slowing, while tropical forests may continue to take up carbon for many years,” said Dr. David Schimel, NASA Jet Propulsion Laboratory senior research scientist and lead author of a paper on the study.

Forests use human-made emissions to grow faster, which in turn reduces the amount of carbon dioxide in the atmosphere—an effect known as carbon fertilization. They also remove up to 30 percent of airborne human emissions through photosynthesis. If those processes slowed down, the rate of global warming would increase.

Why was it important to determine which kind of forest are more adept at that process?

Because the answer “has big implications for our understanding of whether global terrestrial ecosystems might continue to offset our carbon dioxide emissions or might begin to exacerbate climate change,” said Britton Stephens, co-author of the study and a scientist at the National Center for Atmospheric Research.