• DOWNLOAD PORTALS •
Government agencies, academic institutions, advocacy organization and businesses often operate websites with FTP (File Transfer Protocol) capability. This makes it possible for interested users in the geospatial technology community to get high-credibility data straight from the authors for use in their desktop GIS work.
The gold standard for download portals is a bunch of State and Federal government websites that exist soley for the purpose of data distribution (aka "data gateways", "data marts" or "data clearinghouses"). The products typically available on these sites are complete databases pulled from a robust archive and tranferred intact to users. Full documentation for each database is usually included in the downloaded fileset. It would be great if we could get everything we needed from the high-end data portals, but sometimes we need to turn to less robust options. Web-mapping applications, which are primarily used to compose informative on-screen maps, often offer users the ability to download limited-sized chunks of their source data.
State-Level and Local-Level Data
- Michigan Geographic Data Library is used by the state's Department of Technology, Management & Budget to distribute their spatial data.
- Outagamie County Data Download is used by the county's Land Information Office to distribute selected databases from their geographic information system.
- WisconsinView.org is a UW-Madison based program that distributes Wisconsin-specific aerial photography, Landsat imagery, LiDAR-derived elevation data, flood data and tornado data.
US Federal-Level Data
- National Atlas Data Download is used by the National Atlas to distribute their library of small-scale (1:10,000,000 and 1:1,000,000) spatial databases.
- National Map Viewer is a web-mapping application used by the US Geological Survey to distribute a variety of their background maps, base data layers and natural hazards data
- Natural Resources Conservation Service Geospatial Data Gateway (GDG) is used by NRCS to distribute data from a number of important programs. The Watershed Boundary Dataset, the National Agriculture Imagery Program and its predecessors, USGS scanned topographic maps, SSURGO and STATSGO soil surveys and the National Elevation Dataset are a few examples of data resources accessible via the GDG.
- US Forest Service FIA Data Mart is used by the Forest Service to distribute data from the Forest Inventory and Analysis National Program
- US Forest Service Raster Data Gateway is used by the Forest Service to distribute data from several map programs - FSTopo, Primary Base Series (PBS), Secondary Base Series, National Forest Biomass Dataset and National Forest Type Dataset
- US Geological Survey Products & Data is used to distribute the Earth Resources Observation and Science (EROS) Center collections including aerial photography (NAPP and NHAP programs), digitized maps, elevation products, land cover and satellite imagery.
Continental-Level (North America) Data
- Geogratis is used by Natural Resources Canada to distribute their maps, data and publications.
- North American Atlas Data Download is used by the National Atlas to distribute their library of small-scale (1:10,000,000) spatial databases.
- Conservation GIS Data is a gateway to the Nature Conservancy's core global spatial data.
- Global Visualization Viewer (GLOVIS) is used by the US Geological Survey to distribute satellite imagery from the ASTER, EO, Landsat, GLS and MODIS programs.
- SEDAC Data Sets is used by NASA's Socioeconomic Data and Applications Center to distribute their data