A new, satellite-based survey released by the UN Food and Agriculture Organization (FAO) provides a more comprehensive picture of changes in the world’s forests, showing forest area continued to decline between 1990 and 2005. The global remote sensing survey estimated the world’s total forest area in 2005 to be 3.69 billion hectares, or 30 percent of the global land area.

The results were presented at a side event to the COP17 meeting in Durban by FAO and technical partners from the European Commission Joint Research Centre (JRC) summarizing the work and initial results of the Global Forest Remote Sensing Survey. This session was the launch of a summary report presenting new results on global deforestation estimates, including estimates of gross and net gain and loss of forest at the global scale, by region and by broad climatic domain (temperate, tropical etc). These new results are important inputs to the work being carried by the UN-REDD Programme countries as well as a range of processes where forest loss and gain are vital such as REDD+ discussions as part of the UNFCCC.

The study showed that the rate of world deforestation, mainly the conversion of tropical forests to agricultural land, averaged 14.5 million hectares per year between 1990 and 2005. The net loss of forest area - in which losses of forest cover are partially offset by afforestation or natural expansion - totalled 72.9 million hectares between 1990 and 2005. The new data also show that the net loss of forests accelerated, increasing from 4.1 million hectares per year between 1990 and 2000 to 6.4 million hectares between 2000 and 2005.

During the launch at Durban, Dr Frédéric Achard from the JRC outlined the technical methods for processing the satellite imagery to get estimates of land cover change focusing on the tree cover as Adam Gerrand from FAO presented the analysis on forest land-use change and the initial results by climatic domain and by regions. Over 100 countries through 200 national experts reviewed the data in a series of workshops around the world. Examples demonstrating the the benefits and use for national forest monitoring work were given from Papua New Guinea by Joe Pokana and from Angola by Mateus Andre who described the involvement of national experts in the review process.

The meeting agenda and presentations are available online here.

For more information on the launch read the FAO Press release.