Atlas of Our Changing Environment
UNESCO's Atlas of Our Changing Environment tracks human impacts on the environment around the globe. Available as a free PDF book, a Google Maps mashup, or as a layer on the Google Earth application (find in the Layers folder "Global Awareness"), this web source graphically shows the sometimes permanent changes caused by human impacts. While the Google Earth layer is spectacular, the Google Maps view is particularly useful, as dropdown menus allow you to navigate by geographic location (such as Aral Sea), by type of impact (Agriculture or Aquaculture) or by type of natural feature (Water), making it easy to illustrate exactly the point you wish to make. Featured sites include both human and natural changes, from population explosion to volcanic eruption.