Element Description
The platform elements enable the specification of platforms used to collect the data available in the dataset. Platforms provided in CMR metadata must be chosen from a controlled keyword hierarchy maintained in the Keyword Management System (KMS). A list of valid platform keywords can be found here: https://gcmdservices.gsfc.nasa.gov/static/kms/platforms/platforms.csv?
Best Practices
Platform keywords are important for the discovery of data. All relevant platforms should be listed for each dataset. It is preferred that more specific platform keyword terms be chosen from the KMS when available. For example, if data were collected from the NASA DC-8 aircraft, it is preferred that "NASA DC-8" be listed as the platform as opposed to the more generic "AIRCRAFT" keyword. If a particular platform keyword is missing from the KMS, it is possible to put in a request to have it added. The KMS is managed by the Global Change Master Directory (GCMD) and new keyword requests may be made through the GCMD Keywords Community Forum.
In the KMS, there is a hierarchy for platform keywords. Platform keywords should be provided in the metadata field corresponding to the appropriate position of the keyword hierarchy, otherwise the keyword will be rendered invalid. For example, the platform short name specified in the KMS should not be provided in the platform 'long name' field in the metadata. When listing platforms a platform short name will always be required. While platform long names are not required, it is highly encouraged that long names be provided if one is listed in the KMS. Many platform short names are comprised of acronyms, so inclusion of the long name provides additional context to a user who may not be familiar with the acronym. Platform keywords are not case sensitive.
It is recommended that platform keywords be assigned in a consistent manner. For example, if data for several collections were collected by the "LANDSAT-8" satellite, it is recommended that the metadata for all of those collections list "LANDSAT-8" as the platform short name. Providing "LANDSAT-8" as the platform in some records, but the more generic "LANDSAT" as the platform in other records, results in an inconsistent experience for a user discovering data. This is especially true for users narrowing down their search results in the Earthdata Search client by using the faceted search options.
Assigning platform keywords for data collected in-situ and for model derived datasets may not always be straightforward.
Examples:
Terra > Earth Observing System, Terra (AM-1)
METOP-A > Meteorological Operational Satellite - A
Element Specification
An unlimited amount of science keywords may be listed (Cardinality: 1..*)
Model | Element | Type | Constraints | Required? | Cardinality |
---|---|---|---|---|---|
UMM-C | ScienceKeywords/Category | String | KMS controlled | Yes | 1 |
UMM-C | ScienceKeywords/Topic | String | KMS controlled | Yes | 1 |
UMM-C | ScienceKeywords/Term | String | KMS controlled | Yes | 1 |
UMM-C | ScienceKeywords/VariableLevel1 | String | KMS controlled | No | 0..1 |
UMM-C | ScienceKeywords/VariableLevel2 | String | KMS controlled | No | 0..1 |
UMM-C | ScienceKeywords/VariableLevel3 | String | KMS controlled | No | 0..1 |
UMM-C | ScienceKeywords/DetailedVariable | String | Uncontrolled (Free-Text) | No | 0..1 |
ARC Priority Matrix
Priority Categorization | Justification |
---|---|
This element is categorized as highest priority when:
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This element is categorized as medium priority when:
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Not Applicable | |
The element is provided, and follows all applicable criteria specified in the best practices section above. |
Dialect Mappings
UMM Migration
None
Future Mappings
History
UMM Versioning
Version | Date | What Changed |
---|---|---|
1.0.0 | Initial Release |
ARC Documentation
Version | Date | What Changed | Author |
---|---|---|---|
1.0 | 5/4/18 | Recommendations/priority matrix transferred from internal ARC documentation to wiki space | Jeanne' le Roux |