photo: Wagner T. Cassimiro via flickr.
New research published in Nature Geoscience shows that the oft-used figure for the contribution of deforestation towards total carbon dioxide is a bit too high. Rather than 20%, as was estimated by the 2007 IPCC report and which would mean that deforestation emissions were greater than the global transport sector, a more accurate estimate is 12%:According to scientists led by Guido van der Werf of VU University Amsterdam, the high estimate was based on out-of-date information derived from forest surveys done in the 1980s and 1990s.
Emissions Vary Yearly
That said, this new 12% estimate is still just that, an estimate. The researchers say that the figure could be anywhere between 6-17%, and is highly variable on a year-to-year basis.
Adding another wrinkle to story:
Peatland Degradation Now Accounted For
Previously, emissions from tropical peatland degradation -- as the land is cleared for agricultural plantation or by logging, the soil starts oxidizing and released massive amounts of stored carbon -- had not been quantified. However, this new research has done so, and says that this emission source could be as high at 3% of global CO2.
So in total, the latest research shows that the contribution to global CO2 emissions from deforestation, forest degradation and peatland degradation is 15%. Less than the global transport sector (note to self: retire that comparison...), but still very much significant.
Financing Forest Protection Tougher
As to the implications for REDD forest protection schemes, currently being negotiated, The Guardian quotes Van der Werf as saying this lower figure makes it harder to reward forest protection as now "you would get less carbon for you money."
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