GeoDCAT-AP v1.0, key aspects of the geoespatial extension 

GeoDCAT-AP, available on the JoinUp portal, is the geospatial extension of DCAT-AP vocabulary designed for the European data portals, whose first working version was released in late 2015 by the working group belonging to the ISA programme.

Geographic information has always played an especially important role in open data movement. It is of vital importance because most information has a spatial component, both from the point of view of mapping and georeferencing of entities (such as POIs) as well as in domains related to the environment and agriculture. In fact, its impact is transversal, and almost any domain can be the subject of spatial analysis. For this reason, it is essential to facilitate the re-use of geographic information.

In this regard, the European INSPIRE initiative (through its Directive 2007/2/EC) promotes the creation of a European spatial data infrastructure, through web platforms known as IDEs, which provide information through APIs based on web services, according to the standards set by the Open Geospatial Consortium.

Moreover, these IDEs follow the technical specifications of INSPIRE metadata, which include rules for description of resources based on ISO 19115 (geographic information metadata) and ISO 19119 (service metadata and catalogues). In this context of interoperability, it is essential to be able to discover automatically new spatial datasets through descriptions (metadata) published by different INSPIRE IDEs . And this is where the GeoDCAT-AP extension is particularly important.

The goal of GeoDCAT-AP is to provide an RDF syntax for binding together INSPIRE schema metadata and ISO 19115, in a way that ISO19115/INSPIRE metadata records can be automatically transformed into RDF harmonized, easily extensible representations.

To the extent that GeoDCAT-AP extends DCAT-AP vocabulary, its main purpose is to provide a set of classes and properties for representing spatial metadata. The working line followed in this first version makes it clear that the intention is to align GeoDCAT-AP with already existing RDF vocabularies, such as Dublin Core and SKOS Core, while at the same time aligning the representation of concepts with the representations of controlled vocabularies such as GEMET, the topics of INSPIRE itself and, of course, Eurovoc.

Nevertheless, it is necessary to clarify that the mission of this vocabulary, GeoDCAT-AP, is only to offer new more expressive mechanisms for publication and discovery of spatial metadata. In no case does this specification replace the INSPIRE directive, nor the regulatory scheme for INSPIRE metadata.

Until now, the most significant example of GeoDCAT-AP adoption is the European Open Transport Net project, a collaborative network formed by cities and regions to add, harmonize and display geographic open data from all areas of European Union administration. This initiative also provides a number of tools for access and analysis of data in order for third parties to re-use the information and develop new products and services. In this case, GeoDCAT-AP is used in conjunction with DCAT-AP to describe geographic datasets, allowing users to search and access information through visual interfaces quickly and simply.

A report by the Open Data Institute on the re-use of open data by enterprises in the UK shows that geospatial data is the information most reused by the British infomediary sector. Up to 57% of the companies surveyed use this resource for their business. These results are another example of the value of geospatial information which, thanks to the efforts of the European community in the development of extensions such as GeoDCAT-AP, can be used to develop initiatives, services and products that impact positively on society.