This Global Change Master Directory (GCMD) keyword set contains a preliminary set of (~100) keywords that represent an observable property, usually geophysical, geo-biophysical, physical, or chemical.
For example: (1) mass_per_unit_area
, (2) hydrological_evaporation
.
The keywords are arranged in a hierarchy. The top levels of the hierarchy represent the part of nature being measured; the lowest levels of the hierarchy are the measurements.
Any person or organization may request an addition, modification or deletion to the keywords. A requester can be from the user community, a provider of metadata to GCMD, or any other GCMD stakeholder.
Further information is available in the Governance and community guide and at the GCMD Keywords Community Forum.
Generic information about the GCMD keywords follows:
The keywords help facilitate the classification and discovery of Earth Science data by providing a rich vocabulary for characterizing the data. The GCMD keywords are used by hundreds of data providers worldwide for categorizing the ~33,000 records stored in the Common Metadata Repository.
For more information about the keywords and how to access them, please visit the Keyword Landing Page. The GCMD User Support staff can be reached at gsfc-gcmduso@mail.nasa.gov. Questions can also be directed to Valerie Dixon at valerie.dixon@nasa.gov.