FGDC RSE to ISO Crosswalks: Identification Information
The RSE dataset_identifier is defined as a “unique string to identify a dataset”. It could fit into one of two ISO elements. The metadata.fileIdentifier is defined as a “unique identifier for this metadata file”. The identifier that is included in the identificationInfo object (metadata.identificationInfo.identificationInfo.citation.identifier) is probably closer to an identifier for the dataset. In many cases these identifiers may be the same or very similar.
The documentation section of the RSE includes citations for data dictionaries, user guides, and scientific papers. The data dictionary reference may be handled by the feature catalog associated with a dataset. There are many citations spread throughout ISO 19115. Some of these may be appropriate for scientific papers or user guides.
The aggregateInformation object may work for associated papers with an associationTypeCode = crossReference and initiativeTypeCode = study.
An online resource in the identificationInformation would be a good place for these links, assuming that they were online.
The RSE Spatial_Domain section includes three new elements: Frame_Area: The area of a frame given in Frame_Area_Units (square miles, square km, etc.). Multiple_Image_Alignment: Information about overlapping datasets (identifier and % overlap). Worldwide_Reference_System: Global notation for Landsat images.
The processing level is in ISO 19115 as an MD_Identifier at a lower level: metadata.imageDescription.processingLevelCode.code. This includes the authority for the processing level definition and the code. Note that inclusion of this information, and the Platform_and_Instrument_Information, in the Identification Information of the RSE essentially makes these items mandatory.
This section provides quick and easily accessible information about mission, platform, and instrument. Similar information is included in the MI_Operation object in ISO 19115-2. This object is defined as “general information about an identifiable activity which provided the data”. The operation.description field is defined as “description of the mission on which the platform observations are made and the objectives of that mission”. The Operation object includes multiple platform and instrument objects, both of which include identifiers, descriptions and citations.
The RSE short and long names for platforms and instruments are derived from the NASA Global Change Master Directory keyword lists for these items. They could be included in MD_Keyword objects with appropriate KeywordTypeCodes (need to be added) and a citation to the GCMD.
Band_Identification or Thematic_Layer_Identification
This section gives either the number of bands and the ID and measurement mode (channel, wavelength, and/or field of view) for each band, or the number of thematic layers and identification information about each of those layers. This information seems potentially redundant at this point in the record. The band information describes the instrument rather than the dataset and shows up again in the detailed instrument description (see Scan_Spectral_Properties). The thematic layers seem more appropriate for 1) theme keywords or 2) the entity and attributes section.
The approach to aggregation taken in the RSE includes identification of the aggregation that the dataset is a member of (the Container_Packet_ID) as well as information about the members of the aggregation (Component_Information). The inclusion of the component information could cause several problems. First, it could become large as more components are added and, more importantly, it has to be maintained in all members of the aggregation as it grows.
The ISO aggregation approach avoids these problems by including only information about the aggregations that the particular dataset is included in (aggregateDataSetName and aggregateDataSetIdentifier) and the reasons for inclusion (associationType and initiativeType).