General Interest
- DATA.gov -- Provides access to datasets generated by the Federal Government and includes descriptions of the datasets (metadata), information about how to access the datasets, and tools that leverage government datasets.
- Data on the Net -- Links to websites offering numeric social science statistical data, data catalogs, data libraries, social science gateways, etc. Provided by University of California, San Diego.
- Google Dataset Search. Beta. A good starting point, searches multiple data depositories.
- Harvard Dataverse Network -- The world's largest collection of social science research data. Free and open to all researchers worldwide to share, cite, reuse and archive research data. Registration required.
- re3data.org -- Global registry of research data repositories that covers research data repositories from different academic disciplines.
International
- UKDataService -- Provides access to over 6,000 digital data collections for research and teaching purposes. Covers an extensive range of key economic and social data.
- Social Science Data Archives -- Australian Data Archive.
Natural Sciences
- EOSDIS -- NASA’s Earth science data from various sources – satellites, aircraft, field measurements, and various other programs. The vast majority of the data is free.
- NASA -- Earth Science data.
- NCDC Data Services -- The world’s largest provider of weather and climate data. Land-based, marine, model, radar, weather balloon, satellite, and paleoclimatic are just a few of the types of datasets available.
- SEDAC -- Socioeconomic Data and Applications Center, is one of the Distributed Active Archive Centers of the U.S. National Aeronautics and Space Administration. Focuses on human interactions in the environment.
- British Geological Survey -- Information and Data page has links to data catalogues and organizations.
Image source: Jorge Royan. Göttweig Abbey Library, Austria. CC BY-SA 3.0. Wikimedia Commons.
