- AfricaMap (Harvard WorldMap Project)
WorldMap solves the problem of discovering where things happen. It draws together an array of public maps and scholarly data to create a common source.
- Arcata Maps/GIS
(City of Arcata)
- ArcGIS - ArcMap Optimized- Landsat Global Land Survey (GLS) Imagery
Global Land Survey (GLS) datasets are created by the U.S. Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA) using Landsat images. These global minimal cloud cover, orthorectified Landsat data products support global assessments of land cover, land cover change, and ecosystem dynamics such as disturbance and vegetation health.
- Association of Bay Area Governments
Includes Census, earthquake and other hazard geospatial data.
- Atlas of Historical County Boundaries
Author: Newberry Library -- Dr. William M. Scholl Center for American History and Culture
The Atlas presents (in maps, text, and downloadable GIS data) complete data about the creation and all subsequent changes (dated to the day) in the size, shape, and location of every county in the fifty United States and the District of Columbia. It also includes non-county areas, unsuccessful authorizations for new counties, changes in county names and organization, and the temporary attachments of non-county areas and unorganized counties to fully functioning counties. The principal sources for these data are the most authoritative available: the session laws of the colonies, territories, and states that created and changed the counties.
Coverage: 1788 - present
(California Energy Commission) Includes GIS data sets that identify potential climate change risks in specific geographic areas throughout California.
- Cal-Atlas Geospatial Clearinghouse
This government site provides free downloads for frequently used datasets of California, including basemaps, elevation, transportation, political boundaries, scanned USGS topographic maps and 2005 and 2009 aerial photography.
- Cal-Atlas Geospatial Clearinghouse: Map Surfer v2.0 - Imagery Download Tool
This interface allows you to easily locate and download California DRGs, DOQQs, NAIP Imagery, HiRes Urban Imagery, and Landsat Imagery.
- California Environmental Information Catalog
An online directory for reporting and discovery of information resources for California. Participants include cities, counties, utilities, state and federal agencies, private businesses, and academic institutions that have spatial and other types of data resources.
- California GAP: GIS Data
(California GAP Analysis Project) Contains GIS data sets developed for the California GAP Analysis Project. Data is available in statewide datasets or in subsets by ecological region and is available in ARC/INFO export file format. Datasets include landcover, land stewardship and ownership, Jepson ecological region boundaries, predicted distribution of 455 terrestrial vertebrate species, and other basic reference datasets. The same data is available on the GAP Analysis of Mainland California: An Interactive Atlas of Terrestrial Biodiversity and Land Management (Atlas QH 76.5 C2 C34 1995).
- California Geographical Survey
(California State University, Northridge) Includes DEM data for California.
- California Geoportal
(California Technology Agency) Search and discover geospatial data on California. Searches can include California, federal, ArcGIS online and Oregon sources.
- California Geospatial Data
(University of Arkansas Libraries) Links to California state agencies and other sources that have geospatial data available.
- California GIS Map and Information Sites
(Coordinated Legal Technologies) Directory of county GIS sites.
- California Spatial Information Library (CaSIL)
This state government site allows you to download free frequently used datasets for California, including vector data, DRGs, DOQQS, and other image data.
- California Vegetation Map Catalog
(Information Center for the Environment) Contains metadata records for more than 50 California vegetation map data sets. Searchable by county, ecoregion, or hydrologic unit.
- Center for International Earth Science Information Network - CIESIN
(Columbia University) Specializes in data and applications related to human interactions with the environment.
- Central Coast Joint Data Committee
Encompasses the central coast of California
- City of Davis — Mapping & Geographic Information Systems
Online maps and downloadable digital layers for the City of Davis
- CropScape - NASS CDL Program
The geospatial data product called the Cropland Data Layer (CDL) is hosted on CropScape. Currently, all historical products are hosted, available for use and free for download through CropScape.
- Data Access Tools from the Census Bureau
Access Tiger/Line files, downloadable decennial census data, and equal employment opportunity data from this website. Also links to American Factfinder, where data can be searched and tables can be generated and downloaded.
- Data Basin
(Conservation Biology Institute) Search for spatial datasets, maps, people and centers of expertise that focus on conservation. Download available datasets.
Data.gov increases the ability of the public to easily find, download, and use datasets that are generated and held by the Federal Government. Data.gov provides descriptions of the Federal datasets (metadata), information about how to access the datasets, and tools that leverage government datasets.
- Database of the Geologic Map of North America--Adapted from the Map by J.C. Reed, Jr. and others (2005)
The Geological Society of America’s (GSA) Geologic Map of North America (Reed and others, 2005; 1:5,000,000) shows the geology of a significantly large area of the Earth, centered on North and Central America and including the submarine geology of parts of the Atlantic and Pacific Oceans. This map is now converted to a Geographic Information System (GIS) database that contains all geologic and base-map information shown on the two printed map sheets and the accompanying explanation sheet.
- DFG GIS Clearinghouse
(California Department of Fish and Game)
(US Geological Survey) Identify geospatial products available from the US Geological Survey including aerial photography, satellite imagery, digital orthophoto quads, digital line graphs, digital elevation models, digital raster graphics, and other map products. Determine spatial coverage by defining coverage on a map, entering geographic coordinates, or entering a place name.
- Environmental Data Explorer
(United Nations Environment Programme) Includes data sets used in the Global Environment Outlook (GEO) report and other environment assessments. The database holds more than 400 variables that are available as national, subregional, regional and global statistics or as geospatial data sets (maps). Topics covered include themes like Freshwater, Population, Forests, Emissions, Climate, Disasters, Health and GDP. Data can be displayed on-the-fly as interactive maps, graphs, data tables or downloaded in different formats.
- ESRI's Downloadable Data site
This commercial site has both free and for-fee downloadable files.
- Eureka Geographic Information System
(City of Eureka)
- FAO GeoNetwork
(Food and Agriculture Organization of the United Nations) Includes interactive maps, GIS datasets, satellite imagery and related applications.
- FRAP Data
(California Department of Forestry and Fire Protection. Fire and Resource Assessment Program) Contains approximately 50 datasets in ARC/INFO or shapefile export format that relate mainly to California forestry, fire, land use, and vegetation.
- Free GIS Datasets
Categorized by physical geography, human geography and by individual country/area.
(US Geological Survey) Major gateway to national, state and local geospatial data. Browse or search 400,000 records.
The GIS DataDepot has numerous data holdings that are available for free download, additional data can be downloaded via a "Premium" option or written to CD-ROM for a fee.
- GeoConnections Discovery Portal
(Canadian Geospatial Data Infrastructure) Guide to geospatial data, organizations that provide data, and services provided by Canadian and other international organizations.
(State of California) Part of Data.CA.gov
The OpenGeoportal was collaboratively developed as an open source, federated web application to discover, preview, and retrieve geospatial data from different repositories. Several of the country's leading universities and a state agency have formed a partnership to make thousands of geospatial data layers available through a single, open source interface. The application also incorporates some new innovative search techniques. Partners include Tufts, Harvard, MIT, Princeton, MassGIS, Stanford and UC Berkeley.
(CERES) Use a map interface to find and retrieve geographic and environmental data from the California Resources Agency and other partner organizations. Drill down through a map of California using predefined geographies like zip code, watershed, bioregion, county, urban area or by place name. Once an area of interest is identified, you can retrieve digital orthophoto quads; scanned USGS map sheets; a list of rare species and natural communities inventoried by the California Natural Diversity Data Base; and other datasets and projects.
- Geographic Network Explorer
(Geography Network) Directory of free and commercial GIS data. Search by placename, data content, and data theme.
Federal agencies and their partners collect and manage large amounts of place-based (geospatial) data. The Geospatial Platform is an Internet-based capability providing shared and trusted geospatial data, services, and applications for use by the public and by government agencies and partners to meet their mission needs.
- Geospatial and Attribute Links
(University of Arkansas Libraries) Lists attribute and geospatial resources available at a national level and individually by state.
- Geospatial Data
(US Forest Service. Pacific Southwest Region) Includes geospatial data for national forests in California, along with regionwide, provincewide, and statewide datasets. Includes existing vegetation on national forests and other lands in California through a cooperative mapping program with California Department of Forestry and Fire Protection.
- GeoSpatial Data Downloads
(US Bureau of Land Management.California Office)
- GIS Data Depot
(Geocommunity) Includes GIS data for the individual countries, states and counties. Some data products are free (DEM, NWI, DLG, LU/LC, and TIGER). Other data products (DRG, DOQ, DOQQ, FEMA) are available for purchase at a nominal fee.
- GIS Data Depot: California
(Geocommunity) Includes Statewide Data and Countywide Data.
- GIS Data Depot: Humboldt County, Del Norte County, Siskiyou County, Trinity County and Mendocino County
(GIS Data Depot) Datasets available for downloading for each county include DEMs, DLGs, DOQs, DRGs, FEMA Q3 Flood Data, Land Use/Land Cover and 2000 TIGER/Line files.
- GIS Inventory
(National States Geographic Information Council) Gateway to state, county and city data.
- GISUser.com - 2009 GIS Spatial Data Clearinghouse Directory
A compilation of GIS data portals from U.S. states.
- Historical GIS Clearinghouse and Forum (Association of American Geographers)
The Historical GIS Clearinghouse and Forum provides a central reference point for scholars seeking to access or catalogue projects that apply geographic technologies to historical research.
- Home - census.ire.org
Investigative Reporters and Editors is pleased to announce the next phase in our ongoing Census project, designed to provide journalists with a simpler way to access 2010 Census data so they can spend less time importing and managing the data and more time exploring and reporting the data.
- Humboldt Bay and Eel River Delta Data Inventory
Prepared by the Humboldt Bay Harbor, Recreation and Conservation District and PhotoScience
- Humboldt Bay Atlas
(Humboldt Bay Harbor, Recreation and Conservation District) Geographical information system containing biological, physical and infrastructure data for Humboldt Bay; includes interactive maps, pdf maps and a depository of downloadable gis coverages.
- Humboldt County GIS Data Download
(Humboldt County Planning Division)
- International Geospatial and Attribute Links
(University of Arkansas Libraries) Lists resources by country or region.
- Lake Tahoe Data Clearinghouse
(U.S. Geological Survey Western Geographic Science Center) Includes general information, digital data, online maps and images of Lake Tahoe.
LandScan provides ambient population (24-hour average) data by country, administrative unit (state/province), pixel (sq km), and custom area. Data is broken down by gender ratio and age group. Access is provided by East View Geospatial through the East View LandScan Global Web Applications. Coverage is from 2000-2014. Off-campus access is available through campus client VPN.
Data can be downloaded from the Web App for use in GIS software. GIS users can also access the data directly through their GIS software using the Web Map Service (WMS) or Web Coverage Service (WCS) , though this access has been spotty, especially off-campus
- Maps and GIS Resources: United States, by State
(University of Oregon Libraries) Lists major data servers for each state
- Mojave Desert Ecosystem Program
The Data Explorer and the Data Index can be used to identify and access natural resource geospatial data for the entire Mojave Desert ecoregion.
- National Atlas home page
Create online maps or download data collected from more than 20 U.S. federal agencies
- National Geologic Map Database
The Data Portal is intended to: 1) give you a quick browse and query of our Nation's geologic maps, in a standardized format, and 2) link you to the source information found via the NGMDB Map Catalog and Geologic Names Lexicon.
- National Historical Geographic Information System
The National Historical Geographic Information System (NHGIS) is a project to create and freely disseminate a database incorporating all available aggregate census information for the United States between 1790 and 2010. Census Tract Shapefiles are available for select areas for the 1940 - 2010 census.
Free access, but requires you to register and login to use.
Date: 1790 - 2011
- Natural Earth
(North American Cartographic Information Society and other sponsors) Contains public domain vector and raster map datasets at 1:10m, 1:50m, and 1:110 million scales. For each scale, datasets are listed under Cultural, Physical, and Raster themes. Unlike other datasets intended for scientific analysis or military mapping Natural Earth datasets are designed to meet the needs of production cartographers.
- Natural Resources and Environment: Databases/Information Systems
From the Food and Agriculture Organization of the United Nations (FAO), databases about agricultural land use and soil worldwide.
- NGA Raster Roam
Satellite images from the National Geospatial Intelligence Agency at various resolutions.
- Northern California
(US Environmental Protection Agency. Environmental Monitoring and Assessment Program) Dataset produced for the Western EMAP Northern California Pilot Study Area (NCPSA). The dataset study area boundary includes the Pacific Ocean coastline from Tomales Bay in California extending to the mouth of the Rogue River in Oregon on the west, trends along the Oregon-California state line to near Goose Lake on the north, and follows the western edge of California’s Central Valley to a location near the community of Petaluma on the east and south. The purpose of the dataset is to help resource managers better "understand and access the status and trends in the condition of the area's ecological resources and the stressors affecting these systems."
- Northern Sierra Nevada Geographic Information Systems
(Sierra Planning Organization and Sierra Economic Development District)
Open source, federated web application to discover, preview, and retrieve data housed in geospatial respositories.
- Sacramento Area Council of Governments (SACOG) Mapping Center
Includes reference maps, downloadable gis data and an interactive mapper for the counties of El Dorado, Placer, Sacramento, Sutter, Yolo and Yuba.
- San Diego Geographic Information Source (SanGIS)
(City and County of San Diego) Geographic data warehouse that includes a map gallery, an interactive mapper and downloadable geospatial data.
- San Francisco Bay Area Regional Database (BARD)
(U.S. Geological Survey Western Geographic Science Center) Includes the Bay Area Digital Map Library.
- SANDAG Maps and GIS
(San Diego Association of Governments) Includes several interactive mappers and downloadable geospatial data.
- School District Demographics System - Data Viewer
Map or download demographic data about school districts and other geographies.
- SNEP Map/Data Site
(Sierra Nevada Ecosystem Project)
- Southern California Association of Governments Data Center
(Southern California Association of Governments) Search metadata information and download data.
- The National Atlas of the United States
Downloadable map layers from the United States Geological Survey (USGS). Most of the map layers were compiled at a scale of 1:2,000,000 and cover the full geographic extent of the United States of America, although some cover the conterminous United States only. Some map layers include Puerto Rico and the U.S. Virgin Islands.
- UC Atlas of Global Inequality
Time series maps of the world enable the user to see changes in global patterns of inequality every 10 years from 1960 to 2000. With these map sequences you can examine changes in life expectancy, GDP (Gross Domestic Product) per person, and many other measures. An interactive database enables you to produce tables and graphs showing change in selected indicators for chosen countries and periods.
- United States | ArcGIS Resource Center
Vector data for the United States
- University of Maryland, Global Land Cover Facility
The GLCF is a center for land cover science with a focus on research using remotely sensed satellite data and products to access land cover change for local to global systems.
- US by State | Stanford University Libraries
Links to U.S. state geospatial data portals
- US Census Bureau's Cartographic Boundary Files
Download boundary files that are selected generalized extracts from the Census Bureau's TIGER geographic database and are designed for use in a Geographic Information System (GIS) or similar mapping system.
US2010 presents here a Longitudinal Tract Data Base (LTDB), which provides public-use tools to create estimates within 2010 tract boundaries for any tract-level data (from the census or other sources) that are available for prior years as early as 1970.
- USDA Geospatial Gateway
The Geospatial Data Gateway (GDG) from USDA Natural Resources Conservation Service is the One Stop Source for environmental and natural resources data. The Gateway allows you to choose your area of interest, browse and select data from our catalog, customize the format, and have it downloaded or shipped on CD or DVD. Data sets include: Common Land Units, Transportation, Government Units, Census, Landmarks, Digital Raster Graphics (DRG), Elevation, Ortho Imagery, Landuse/Landcover, Geology, Soils, Precipitation, Temperature.
- USGS Africa Ecosystems Mapping
The USGS RMGSC has modeled the distribution of terrestrial ecosystems for Africa using the global mapping methodology that was developed from a deductive, biophysical stratification approach to delineate ecosystems by their major structural elements. Each major structural component of ecosystems (land surface forms, surficial lithology, bioclimates, topographic position, and so forth) were modeled for the continent at the highest possible resolution and then spatially combined to produce a new map of biophysical settings for the continent, termed ecosystem structure footprints. Each structural footprint represents a unique combination of the input layers resulting from the union, and the result is a biophysical stratification of the continent into a set of unique physical environments. These ecosystem structure units characterize the abiotic (physical) potential of the environment.
- USGS Geographic Data Download
Links to information on DEMs, DLGs, and land use/land cover data from the USGS.
- USGS/EROS Find Data
Portal including aerial photos, satellite imagery, land cover and elevation data, and digitized maps.
(Lakes Environmental Software) Provides easy to use map interface for downloading DEMs, DLGs,and Land Use and Land Cover (LULC) data.
- Websites for Digital GIS Data
Stanford University's Branner Library site that provides many useful links to GIS Data resources.
- Welcome to NHGIS — National Historical Geographic Information System
The National Historical Geographic Information System (NHGIS) provides, free of charge, aggregate census data and GIS-compatible boundary files for the United States between 1790 and 2000.
- World Resources Institute Congo Basin Forest Atlases
The Congo Basin Forest Atlases are a living forest information system, merging the latest technology in remote sensing and GIS with ground-truthing to monitor and sustainably manage forests. WRI works in the following Congo Basin countries: Cameroon, Central African Republic, Congo, Democratic Republic of Congo, Equatorial Guinea, and Gabon.
- World | ArcGIS Resource Center
Vector data for the world, downloadable into ArcGIS.