The EarthPortal Metadata Schema is built upon the Metadata Vocabulary for Ontology Description and Publication (MOD 2.0). This comprehensive schema integrates various vocabularies, such as Dublin Core, OMV, DCAT, and VoID, and was introduced by Dutta et al. 2017. Its primary purpose is to empower ontology developers to annotate and describe their ontologies, while also enabling ontology libraries to provide semantic descriptions of ontologies in the form of linked data.

EarthPortal with other members of the OntoPortal Alliance has embraced a set of 106 elements, comprising classes and properties organised into distinct categories. Each metadata element is linked to a FAIR principle, adding a layer of semantic richness to the description. The assessment of metadata elements is facilitated through the O’FAIRe tool, ensuring a systematic evaluation of the ontology’s Findability, Accessibility, Interoperability, and Reusability aspects.

EarthPortal administrators encourage the creators of semantic artefacts to compile the metadata fields by adding as much detail as possible to ensure the accurate communication of information to users and to be compliant to the FAIR principles when publishing a resource.