On the occasion of the launch of the Landsat Data Continuity Mission (LDCM)*, the eighth Landsat satellite, NASA and the USGS have published a book about how Landsat data is used to serve society. The chapter on forests is made up of interviews with IES scientists on how the IES uses Landsat data for forest monitoring.
Landsat – Continuing to Improve Everyday Life, is a beautifully illustrated book that gives concrete examples of how Landsat imagery is used in helping to monitor and manage natural disasters, land use and land cover change, water use, food, ecosystems, and forests. In the chapter on forests, IES scientist Alan Belward emphasizes how important it is to monitor and make sensible decisions on how to manage forests and other natural resources. He explains how he and his colleagues contributed to a global remote sensing survey for the UN Food and Agriculture Organization (FAO)’s Global Forest Resource Assessment of 2010 which incorporates Landsat satellite measurements of forest extent for 13 000 plots around the world for the years 1990, 2000 and 2005. IES scientist Frédéric Achard explains how this was made possible thanks to the granting of free access to Landsat data, which can pick up subtle changes in the forest canopy and is of a fine enough resolution to provide accurate estimates of deforestation (each pixel in a Landsat image measures 0.09 ha or 900m2) .
The fact that Landsat satellites collected images of the Earth for over 40 years also makes it possible to determine how forests are changing. Alan is quoted as saying that about 180 million acres of forest were lost between 1990 and 2005. “We’re losing about a football field worth of forest every four seconds of every day. That’s net loss. That’s including all the new trees that have been planted around the world.”
The IES supports the Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (REDD+) initiative of the United Nations Framework Convention on Climate Change (UNFCCC). Under REDD+, donor countries provide incentives to developing countries to reduce their deforestation and degradation rates and to leave their forest intact so as to minimise net global carbon emissions and mitigate climate change. Developing countries will set carbon emission reference levels based on past rates of deforestation, and for this they need historical estimates. Accurate annual estimates of historical and current emissions, which Landsat can help generate, will be rewarded by larger payments.
* The LDCM (Landsat 8), launched on 11 February 2013, is the latest in the series of Landsat satellites, which have been recording images of the Earth’s surface for over 40 years, since 1972. The Landsat satellites provide decision makers with key information about the world’s food, forests, water and how these and other land resources are being used.