How to connect your data centre

The GCW Data Portal is a metadata driven data portal. This implies that data are hosted and served by contributing data centres which expose discovery metadata on the datasets. Once initiated, the GCW Data Portal regularly (once daily) harvests discovery metadata from the contributing data centres and ingests this in the GCW Data Catalogue which is integrated in this site. Provided the data is provided in the appropriate form (encoding) the GCW Data Portal is developing software to transform and combine datasets as well as extracting the most recent observations for ingestion into WMO GTS if required by the GCW community.

In order to connect your data centre to the GCW Data Portal an OAI-PMH end point serving either GCMD DIF or ISO19115 discovery metadata is required. If ISO19115 is used, discovery metadata should include GCMD Science Keywords to describe the parameters measured. If your data centre is hosting much data and GCW relevant data is mixed between other data, a dedicated OAI-PMH set is welcome to simplify the harvest process for the portal. When you serve GCMD DIF discovery metadata this is quite straightforward if the standard is used. If you use ISO19115 we require to add GCMD Science Keywords to describe the content of a dataset. Furthermore we require URLs to be identified using the OSGeo keywords for catalogue Interoperability.

Other technologies (OGC CSW and OpenSearch) are explored and to a certain extent support, but the simplest way forward is to use OAI-PMH.

For data we build services that rely on data encoded according to the Climate and Forecast Convention. This can be NetCDF file, but preferable data served through OPeNDAP as OPeNDAP allows us to do data streaming without downloading files. When preparing NetCDF (or other data) we recommend that the Attribute Convention for Dataset Discovery (ACDD) is used to include discovery metadata in the files. If you prepare NetCDF/CF files with ACDD we offer a compliance checker that you can access through this site at https://gcw.met.no/dataset_validation/form. Discovery data should include links to e.g. OGC WMS GetCapabilities and OPenDAP for the datasets. Please remember that we need GetCapabilities per dataset, but many datasets included in the same GetCapabilities document.