Deutscher Wetterdienst Markus Heene, DWD DAR Metadata
Page: 2DAR Metadata Catalog Agenda Welcome Notes Metadata record types & associated datasets DAR Metadata Identifiers Introduction to DWD DAR metadata approach for GISC – conformance part Requirements for DWD DAR metadata generator DWD DAR Metadata generator – architecture XML template for DAR metadata Usage and some facts Points for discussion
Page: 3DAR Metadata Catalog Notes I’m not member of IPED-MDI This presentation is an introduction to DAR Metadata For this presentation –DAR Metadata are XML files –Are well-formed XML documents –Validate against a schema (ISO 19139) –ISO defines an XML representation for ISO metadata This presentation shows DWDs approach to produce DAR Metadata
Page: 4DAR Metadata Catalog
Page: 5DAR Metadata Catalog Metadata record types & associated datasets Metadata Record A describes a dataset of bulletins which are stored in the 24-hour cache of the GISC. The metadata record A is equivalent (although more informative) to a record in WMO vol C1 & describes the normal contents of this type of bulletin; for example SYNOPS from several observation stations; including MLO (Mauna Loa, Hawaii). Metadata record B describes a long-term climate record from station MLO which is comprised of a collection of SYNOPTIC observations from, say, 1954.
Page: 6DAR Metadata Catalog Metadata record types & associated datasets Whilst both datasets are continually changing, both metadata records are ‘quasi-static’; only needing to be changed when the observation regime changes (i.e. a new instrument is deployed or the exact observation location changes) The critical differences between records A & B in this example are: –Temporal extent: A has a relative temporal extent in any 24-hour period, whilst B has a temporal extent from 1954 to (almost) present day; –Citation authority: authority for A is int.wmo.wis, whilst B is gov.noaa –Quality control: the dataset described by B may have undergone additional quality control to validate the observation record for inclusion in a long-term archive Whilst the meeting noted that there may be significant overlap between A and B, one cannot assume that overlap exists. The meeting concluded that metadata records A and B describe entirely different products!
Page: 7DAR Metadata Catalog DAR Metadata Identifiers urn:x-wmo:md: –int.wmo.wis –de.dwd Separator is “:” Examples –urn:x-wmo:md:int.wmo.wis::SMAA01EDZW –urn:x-wmo:md:int.wmo.wis::FCUK31EGRR –urn:x-wmo:md:cn.gov.cma::NMC.NWP.HCXA05BABJ Case insensitive check for duplication Check uniqueness of a DAR Metadata Record –gmd:MD_Metadata/gmd:fileIdentifier –gmd:MD_Metadata/gmd:dateStamp
Page: 8DAR Metadata Catalog Live Demo
Page: 9DAR Metadata Catalog Introduction to DWD DAR metadata approach for GISC – conformance part ISO conformance WMO conformance INSPIRE conformance –European Commission Directive ( –More demanding than ISO –Implementing guidelines (paper with 74 pages) ( –Increase metadata by ~ 20%
Page: 10DAR Metadata Catalog Requirements for DWD DAR metadata generator Metadata conforms to WMO, ISO and INSPIRE Automatic generation of metadata Basic information is stored in GISC database model Bulk generation for tests of DAR catalogues Logging: need to identify easily issues Extendable and maintainable Reusable for other components Easy to distribute
Page: 11DAR Metadata Catalog DWD DAR Metadata generator - architecture XML template Database XSLT templates read data DBReader MetaDataFileGen. read template 1 2 WorkFacade 3 process template ISO schema 4 do XSLT 5 validate document 6 output document Metadata
Page: 12DAR Metadata Catalog XML template for DAR metadata Template is ISO and INSPIRE conform Based mainly on examples from Jürgen (DWD) and inspirations from CMA, JMA and Météo France Nodes you may wonder about: – : map navigation (theme), alternative tag (well- defined by ISO, only 2 or 3 revelant entries for meteorology in enumeration) – : we need this for INSPIRE – : based on April 2009 workshop with CMA we use this element for priorities of products – : each metadata record should contain one bounding box, in addition this extent contains no separate for (INSPIRE) – : we need this for INSPIRE
Page: 13DAR Metadata Catalog Usage and some facts Usage: –Whole production is based on ant (all necessary libs, source code for metadata generator are provided) –Customize build.properties to your needs (check documentation) –Load basic information for metadata generation into DB –Type “ant” at CLI that’s it Facts: –Roughly 1 sec per metadata document on standard PC –Metadata are reviewed by external company (con terra) received positive feedback, suggestions for improvement are already implemented –Still prototype software
Page: 14DAR Metadata Catalog DAR Metadata exchange GISC to GISC –OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting) –Example Implementations: jOAI OAICat NC/DCPCs uploading DAR Metadata to GISC –GTS: file-naming-convention
Page: 15DAR Metadata Catalog Resources and further information IPED-MDI – Final Report I/report/Report_IPETMDI_I_ dochttp:// I/report/Report_IPETMDI_I_ doc INSPIRE Editor - INSPIRE Metadata Implementing Rules pdf 16.pdf
Page: 16DAR Metadata Catalog Q&A