Disturbed rainforests release more carbon dioxide than they absorb

Deforestation in the Amazon. Photo: Marcelo Horn / iStock

Tropical rainforests are known for their greenhouse gas gobbling abilities, but human impacts may have changed that. According to a study published Thursday in Science, tropical rainforests may be emitting more CO2 than they soak up.

"Much of that carbon contribution is due to deforestation … but more than two-thirds comes from a less visible source: a decline in the number and diversity of trees in remaining forests," writes Carolyn Gramling for Science News.

Yes, but: NASA scientist Joshua Fisher told Science News that this study only looked at above-ground carbon. Much CO2 is absorbed by rainforest soils, and atmospheric data still indicates that rainforests are net carbon absorbers, not emitters.