- CEOS International Directory Network
An international effort headed by the Committee on Earth Observation Satellites developed to assist users in locating Earth science data sets, data services, and visualizations using DIF metadata.
- Global Change Master Directory
The GCMD uses DIF metadata to promote the discovery, access, and use of Earth science data and data-related services worldwide, parcitularly focusing on NASA data.
- DIF - Directory Interchange Format
An early metadata initiative from the Earth sciences community, intended for the description of scientific data sets. It inlcudes elements focusing on instruments that capture data, temporal and spatial characteristics of the data, and projects with which the dataset is associated.
- Repository-Developed Metadata Schemas
Some repositories have decided that current standards do not fit their metadata needs, and so have created their own requirements.