Tropical Forests Fight Carbon Better Than We Hoped

And just when we thought it was all bad news, a study recently led by NASA experts has revealed that the Earth's tropical forests are somehow absorbing more carbon dioxide (CO2) than experts thought possible, taking the harmful greenhouse gas from our atmosphere at unprecedented rates.

The study, recently published in the journal Proceedings of National Academy of Sciences (PNAS), details how NASA experts and their peers determined a stunning new way to conduct the normal "apples-to-apples" comparison between various forms of vegetation as a carbon sink. Namely, the researchers discovered how to differentiate between and measure carbon absorbed by various forests across the globe.

That kind of knowledge not only helps scientists make more accurate and detailed carbon-cycle models, but it also helps experts better focus conservation efforts, highlighting what kinds of forests in what parts of the world are invaluable in the fight against greenhouse gas release.

Forests and other land vegetation currently remove up to 30 percent of human carbon dioxide emissions from the atmosphere during photosynthesis, but thanks to this latest study, experts now know that we have tropical forests to thank for a great deal of this work - absorbing a whopping 1.4 billion metric tons of CO2 out of a total total global absorption of 2.5 billion metric tons. That's more than what is absorbed by most boreal forests types (as found in Canada, Siberia, and other northern regions) combined!

"This is good news, because uptake in boreal forests is already slowing [with climate change], while tropical forests may continue to take up carbon for many years," lead researcher David Schimel, of NASA's Jet Propulsion Laboratory, said in a statement.

He explains that while some studies have shown that all trees can benefit from cranked carbon levels to a point, the consequential hiked temperatures in the north are leaving boreal forests unhealthy, and thus their carbon sink potential is dwindling. Meanwhile, tropical forests are quite used to heat, and can be commonly found in regions that are suffering from climate change in other ways (not necessarily with temperature spikes).

In that sense, it's a wonderful stroke of luck that tropical tree species are the greater carbon sink, as "tropical forests may continue to take up carbon for many years," Schimel said. (Scroll to read on...)

He added that with hiked carbon levels, these tropical species will grow faster and make greater use of their photosynthetic processes, taking in more CO2 along the way.

That result "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," added co-author Britton Stephens of the National Center for Atmospheric Research.

However, it's important to note that this won't really change much in terms of conservations trends, especially since the battle against deforestation has already been aimed at rainforests across the globe.

That in-part has to do with the fact that researchers have long thought that slash-and-burn tactics used in regions like Ecuador and Brazil for the sake of making livestock pastures was dumping far more carbon back into the atmosphere than the remaining forests could ever hope to make up for. Worse yet, what fractured forests remain would start to suffer from "lonely tree syndrome," in which their health and potential as a carbon skink drops severely.

Now, according to the researchers, we can be more certain that protecting these tropical forests is a very high priority in the battle against carbon-driven climate change. And, happily, we now also suspect that tropical forests can in fact make up for the released carbon of their fallen brethren... to a point, of course.

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