Expansion of degraded land in Ferlo region of Senegal

Images from the Ferlo region of Senegal show the degredation of land between 1994 and 2011. The images are included in the U.S. Geological Survey Earth Resources Observation and Science Center book "Landscapes of West Africa: A Window on a Changing World." Geographer G. Gray Tappan used rephotography of sites across West Africa over the span of three decades to inform the work included in the atlas.