Google Earth,a an Internet-based service originally developed by Keyhole, became instantly popular when it was rebranded and released by Google in early 2005. It allows users to view the Earth as a whole, zooming from global to local scales, using high-resolution imagery that shows individual buildings and vehicles, and to simulate a magic carpet ride over any part of the Earth’s surface. By releasing an application programmer interface (API), Google enabled thousands of individuals to add their own data and their own applications, and to make them easily accessible to anyone. In many ways, Google Earth represents a dramatic improvement in the accessibility of geospatial data and tools, allowing the general public to explore the Earth’s surface in ways that had previously been available only to geospatial professionals.
In the immediate aftermath of Hurricane Katrina, high-resolution images began to appear on the Google Earth site, showing in detail the impacts of the disaster. People from all over the world could explore the impacted area, seeing the levee breaks in New Orleans, the extent of the flooding, the damage to buildings, and the impacts on the environment. Images from Google Earth appeared on television newscasts around the world. Within the impacted area, however, where computers were damaged, electrical power networks were destroyed, and Internet communications were disrupted, it was impossible for emergency managers to make use of Google Earth’s data and tools for days and in some cases weeks or months. Paradoxically, access to geospatial data and tools resembled a donut—abundant far away from the impact area, but almost nonexistent where it was most needed in the donut’s center.
In this report, the term emergency is used to mean a sudden, unpredictable event that poses a substantial threat to life or property. Emergencies vary in magnitude, depending on the degree of threat, and they also vary in duration and in the geographic extent of their impacts. A disaster