The USGS and Advanced Topographic Development and Images(ATDI) have formed a partnership to distribute USGS geographic data to make more public domain data available at no charge while enabling the private sector to have a greater role in the distribution of USGS data.
The USGS Spatial Data Transfer Standard Digital Elevation Models (SDTS DEMs) being distributed by ATDI describe the topography of the land surface. Private industry, government, nongovernmental organizations, and individual citizens depend on a common set of base information that describes the Earth's surface. They use this information as tools for economic and community development, land and natural resource management, health and safety services, emergency management, defense and environmental protection.
SDTS data contribute to The National Map--a seamless, continuously maintained set of geographic base information that will serve as a foundation for integrating, sharing, and using other data easily and consistently. Additional information about USGS SDTS data is available at mcmcweb.er.usgs.gov.
The USGS is committed to meeting the Nation's needs for current base geographic data and maps. By working with partners, the USGS will continue to provide the Nation with access to current, accurate, and nationally consistent digital data and topographic maps derived from those data.
ATDI is the latest commercial vendor to partner with the USGS to distribute free SDTS DEMs on the Internet. ATDI is an online resource for the location and acquisition of a variety of digital map data. ATDI provides the ICS Map Server package that allows import and export of SDTS DEMs, re-projection, tiling, and generic functions for handling DEMs, Images and Land Cover files. ATDI’s interface allows users to enter a central coordinate and immediately retrieve the selected quadrangles. ATDI also sells a worldwide catalogue of digital elevation models, reference images, and ground occupancy information. The SDTS DEMs are available at this ATDI web site http://18.104.22.168/.
USGS partners will continue to receive SDTS versions of the DEMs as they are made available by the USGS. Native format DEMs are still available for sale from USGS on various media through Earth Explorer.