This is a list of repositories and databases for open data.

ASTRONOMY - An astronomical database provides basic data, cross-identifications, bibliography and measurements for astronomical objects outside the solar system.

ATMOSPHERIC and OCEANOGRAPHIC SCIENCE - This 55-terabyte-and-growing archive, composed of more than 600 datasets, is made up of a high-quality collection of observations and analyzed atmospheric, oceanographic, and related data.

BIOLOGY - A Resource for Studying Biological Macromolecules. The PDB archive contains information about experimentally-determined structures of proteins, nucleic acids, and complex assemblies.

BIOLOGY - A comprehensive, high-quality and freely accessible resource of protein sequence and functional information.

CHEMISTRY - BioAssay Database, Compounds Database, and Substances Database and structures from MIC Scientific.
National Center for Biotechnology Information
NLM | NIH | HHS

COMPUTER SCIENCE - For the promotion of cooperative macroscopic measurement and analysis of Internet traffic and performance, collection of data for scientific analysis of network function.
CAIDA collects several different data types at geographically and topologically diverse locations, and makes this data available to the research community to the extent possible while preserving the privacy of individuals and organizations who donate data or network access.

EARTH SCIENCE - Portal for sharing, publishing, and integrating data. Funded by NSF.

OCEANOGRAPHY - comprehensive sources of marine environmental data and information.

SNOW and ICE - archives cryospheric data. NSIDC acknowledges all data providers in documentation, metadata (Directory Interchange Format (DIF)), and references, and is also willing to hold or restrict data distribution until providers publish.
NASA and NSF

TAXONOMY: organism names, we provide a selection of external links, organism strains and viral host information.
KEYWORDS:Listed on categories and subsets.

Data formats and codes. NODC Code lookup utilities (tools) - Country, Institution, Platform (Ships), Project, Person, Seaname.