Since 1972, the Landsat series of satellites has been completing an orbit of the earth every 84 minutes, recording footage of the surface of our planet. Google Earth software has been used to sort through the data to find the best images and stitch them together into an animation of the changing surface of the earth over the decades. The timelapse brings together trillions of pixels of image data that have never before been available to the public, comprising satellite images from 1984 to 2012.
The footage shows, very clearly, urban expansion, the retreat of glaciers, the disappearing Amazonian rainforest, natural resource extraction (like coal mining and the Tar Sands), irrigation projects in the Middle Eastern deserts, and much more. And this data is available to everyone – members of the public, universities, non-profit groups and governments.
NASA have just launched Landsat 8, but the US Congress is currently deciding whether to continue the whole project. Those involved argue that having this clear picture of the earth and our impacts on it help hold us accountable for what we do, and that this accountability would be harder to maintain if we stop this record and display of the ‘undeniable’ changes we make to our planet.