The world's tropical forests now emit more CO2 than all US cars and trucks combined

Scientists have a wake-up call for the world.

Tropical forests are now a threat in our fight against climate change. They emit more CO2 than all US cars and trucks combined, according to a study recently published in Science. This wasn't always the case.

After all, trees absorb CO2 from the atmosphere. But that's not the whole story. When those trees die, they decompose. This process returns some of that CO2 to the atmosphere.

Thanks to deforestation and sparser forests, dead trees have helped tip the balance.

The devastation is worldwide. The color red on this map indicates annual Co2 emission. Today, tropical forests absorb 1.6 billion metric tons of CO2 per year. But they emit nearly double that, 3.16 billion metric tons per year.

So, overall, they emit 1.56 billion total metric tons of CO2 annually. To compare, US cars and trucks emitted 0.9 billion metric tons in 2015.

That sounds bad, but scientists say there's a silver lining. If we limit deforestation and restore some of the forests, we could drastically reduce CO2 levels in the atmosphere.

Special thanks to lead author Alessandro Baccini for confirming the values of CO2 emissions in this video.