Forests have never been under more pressure. Demand for their natural wealth and a hunger for land causes forest clearance at alarming rates. The UN Food and Agriculture Organization (FAO) estimates that the Earth loses an area about the size of a football field every 3 seconds - in the time it takes to make a sandwich an area equivalent to the National Mall in Washington, D.C., is cleared... somewhere on Earth trees are falling every second of every day.
Based on a systematic sample of Landsat imagery at 4,016 locations around the tropical belt the European Commission's TREES 3 project is making estimates of forest cover change for the years 1990, 2000, 2005 and 2010 with new levels of precision. Preliminary results emphasize just how relentless the pressure on our planet is. Using archived and recent Landsat imagery we have measured dramatic changes to the African Continent for example. Since the 1970s natural vegetation (forests and savannas) have been converted to agricultural land at a tremendous pace. Around 50,000 sq. km per year are cleared - an area twice the size of Vermont. With the fastest growing population in the world such land cover conversions are unlikely to slow down any time soon, nor should the measuring programs. Landsat 8 and its European counterpart, Sentinel 2, are not being launched any sooner than they are needed.