Carbon credit programs overstate forest preservation, study reveals

Projects aimed at offsetting carbon emissions by reducing deforestation overestimate their impact, causing projects to issue more carbon credits than they should. This conclusion is the result of research conducted by scientists from the Vrije Universiteit in Amsterdam and the University of Cambridge. Their findings were published in the academic journal Science on Thursday.

"Only a handful of projects genuinely reduce deforestation, while many others either don't or achieve far less than they claim," says VU researcher Thales West. He added that it is challenging to determine whether this is intentional or unintentional. "We mostly notice methodological errors."

According to the researchers, approximately two-thirds of the carbon credit programs are based on projects with minimal to no real impact on deforestation. They assessed forest projects in Peru, Colombia, Cambodia, Tanzania, and the Democratic Republic of Congo. In their study, they contrasted areas with active projects against comparable regions without any. 16 of the 18 projects claimed to have prevented significantly more deforestation than observed in the comparable areas.

Companies buy the "carbon credits" that these programs sell, allowing them to offset their carbon emissions, at least on paper. Consumers wishing to counteract the environmental footprint of, for example, a flight can use these carbon credits, which are initially acquired by the airline.

The logic behind these projects rests on the fact that trees absorb CO2. Thus, every tree spared from being cut down offsets a certain amount of greenhouse gases. While there are projects that focus on planting new trees, this study exclusively examined the conservation of existing forests.

Andreas Kontoleon, a researcher from Cambridge, highlighted that major polluters leverage carbon credits to enhance their reported climate performance. "However, we find many of the claims about preserving vast areas of forest from logging to be overstated," he noted. He also observed that the calculations of many offset programs are "often overly simplistic."

"If you use a flawed methodology, you're bound to get flawed results," West added. He believes that the certification process urgently requires to be improved.