A revolutionary new approach to measuring changes in forest carbon density has helped scientists determine that the tropical forest regions now emit more carbon than they capture, due to extensive deforestation and degradation.
The landmark paper, “Tropical forests are a net carbon source based on aboveground measurements of gain and loss”, was published online in the October issue of the journal Science.
Dr. Wayne Walker will discuss the paper – as well as the process and implications of this new forest monitoring technology. The lead author on the paper was Alesandro Baccini, also a scientist at the Wood Hole Research Center.
Using 12 years (2003-2014) of satellite imagery, laser remote sensing technology and field measurements, Baccini and his team were able to capture losses in forest carbon from wholesale deforestation as well as from more difficult-to-measure fine-scale degradation and disturbance, which has previously proven a challenge to the scientific community over large areas.
While it can be a challenge to map the forests that have been completely lost, it’s even more difficult to measure small and more subtle losses of forest. In many cases throughout the tropics, forest loss is a result of selective logging, or smallholder farmers removing individual trees for fuel wood. These losses can be relatively small in any one place, but added up across large areas they become considerable.
The technology can help countries quantify changes in their forest carbon stocks – especially in the context of Nationally Determined Contributions under the Paris Agreement. It can also be used to provide more certainty to carbon-offset markets.