The carbon dioxide emissions caused by the destruction of tropical forests have been significantly overestimated, according to a new study. The work could undermine attempts to pay poor countries to protect forests as a cost-effective way to tackle global warming.
The loss of forests in countries such as Brazil and Indonesia is widely assumed to account for about 20% of all carbon dioxide produced by human activity – more than the world's transport system. The 20% figure was published by the Intergovernmental Panel on Climate Change in 2007 and was widely quoted after being highlighted by the Stern review on the economics of the problem. It is repeatedly used by Prince Charles and others as an incentive to push efforts to include forests in carbon trading.
Curbing emissions from deforestation is one of the main issues being discussed at a UN climate meeting in Barcelona this week, before crucial talks in Copenhagen next month.