ABSTRACT
On January 31, 1998, former U.S. Vice President Al Gore described his vision for a Digital Earth-a virtual representation of the Earth connecting the world’s digital knowledge archives. This multi-resolution, three-dimensional representation of our blue planet would make it possible to visualize and make sense of the vast amounts of spatial imagery and geo-referenced information on our physical and social environments.1 Today, satellite and aerial imagery provides humanitarian organizations with a visual representation of the Earth during relief efforts. As noted in Chapter 4, groups like Humanitarian OpenStreetMap, Tomnod, and Zooniverse have all turned to microtasking to make sense of this “Digital Earth.” But even then, microtasking alone can’t actually keep up with 1.5 million square miles (4 million square kilometers) of new satellite imagery produced every day-a figure that will increase substantially within just a few years.2
