Remote sensing tracks relentless urban spread
Looking back through the decades, these snapshots from space — created exclusively for CNN by NASA’s Landsat department in collaboration with the U.S. Geological Survey — reveal the impact of the vast population shift on cities around the world.
http://edition.cnn.com/SPECIALS/world/road-to-rio/satellite-photos-urban-sprawl/index.html
example of LAS VEGAS:
