The JRC recently published a paper in Global Change Biology on tropical deforestation rates and carbon losses over the past two decades.
Using satellite imagery, JRC-IES scientists estimated the changes in forest cover (deforestation and forest regrowth) in the tropics for the periods 1990-2000 and 2000-2010. These results were combined with recent pan-tropical biomass maps to estimate carbon losses. The analysis showed a gross loss of tropical forests, mainly humid forests, of 8.0 million hectares per year in the 1990s and 7.6 million hectares per year in the 2000s.
Carbon remaining in the atmosphere due to loss of forest cover and other wooded land cover was estimated at 887 million tonnes per year for the 1990s and 880 million tonnes per year for the 2000s, which is the equivalent of circa 10% of carbon emissions from fossil fuel combustion and cement production. The annual removals of carbon from forest regrowth were estimated at 115 million tonnes per year for the 1990s, and 97 million tonnes per year for the 2000s.
Deforestation and forest degradation are key issues addressed by the REDD+ mechanism (Reduction of Emissions from Deforestation and forest Degradation) of the United Nations Framework Convention on Climate Change (UNFCCC), which aims at mitigating climate change by reducing emissions of greenhouse gases and removing greenhouse gases through sustainable forest management in developing countries.
Deforestation results in the immediate release of the carbon that was originally stored in the trees. For the Intergovernmental Panel on Climate Change (IPCC), reducing and/or preventing deforestation is the mitigation option that has the largest and most immediate impact on carbon stock in the tropics. For this reason, the inclusion of reducing emissions from land use change is considered to be essential to achieving the objectives of the UNFCCC.
The JRC has been monitoring tropical forests through remote sensing since the early 1990s, with the goal of reducing uncertainties in measuring forest change and related carbon emissions. The study presented in this paper was carried out in support of the Remote Sensing Survey of the Global Forest Resource Assessment of the United Nations Food and Agriculture Organization (FAO). Unlike global country surveys that present tables with national data, this remote sensing survey provides a sample of spatially explicit data distributed across the whole tropical belt. Compared with the cost of carrying out field inventories in the tropics and given the lack of comparable historical national forest inventory data, the use of satellite imagery facilitates the consistent monitoring of forest cover change over very large regions.