Ecological Footprint Calculator - want to know how much of a burden you are to the planet?
Risk Factor from State Street - estimated flood, climate, and earthquake risk by address for the whole country.
Welcome to the Anthropocene - amazing timeline, imagery, cartography, and graphs regarding human impacts on the planet. A product of the remarkable Globaia Project that seeks to meld art and science to educate and inspire the public to action on the environment.
World Wildlife Fund - global environmental non-profit aiming to protect wildlife and human populations.
Google Earth Engine - brings together the world's satellite imagery — trillions of scientific measurements dating back over 40 years — and makes it available online. (Tutorial)
Natural Resources Defense Council - a non-profit organization dedicated to research and advocacy regarding U.S. natural resources.
One Planet, Many People (UNEP), 2000 - amazing atlas by the U.N. dedicated to tracking change on the planet using satellite imagery. Excellent essays explain the issues succinctly.