The U.S. Geological Survey Earth Resources Observation Systems Data Center responds to emergencies in support of various government agencies for human-induced and natural disasters. This response consists of satellite tasking and acquisitions, satellite image registrations, disaster-extent maps analysis and creation, base image provision and support, Web-based mapping services for product delivery, and predisaster and postdisaster data archiving. The emergency response staff are on call 24 hours a day, 7 days a week, and have access to many commercial and government satellite and aerial photography tasking authorities. They have access to value-added data processing and photographic laboratory services for off-hour emergency requests. They work with various Federal agencies for preparedness planning, which includes providing base imagery. These data may include digital elevation models, hydrographic models, base satellite images, vector data layers such as roads, aerial photographs, and other predisaster data. These layers are incorporated into a Web-based browser and data delivery service that is accessible either to the general public or to select customers. As usage declines, the data are moved to a postdisaster nearline archive that is still accessible, but not in real time.
