Deutscher Wetterdienst Markus Heene, DWD [email protected] DAR Metadata.

Deutscher Wetterdienst

Markus Heene, DWD [email protected]

DAR Metadata

DAR Metadata Catalog 24.09.2010 Page: 2

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


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 19139 defines an XML representation for ISO 19115 metadata

This presentation shows DWDs approach to produce DAR Metadata



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.


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!


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


Live Demo


Introduction to DWD DAR metadata approach for GISC – conformance part

ISO 19139 conformance

WMO conformance

INSPIRE conformance – European Commission Directive (http://inspire.jrc.ec.europa.eu)

– More demanding than ISO

– Implementing guidelines (paper with 74 pages) (http://inspire.jrc.ec.europa.eu/reports/ImplementingRules/metadata/MD_IR_and_ISO_20090218.pdf)

– Increase metadata by ~ 20%


Requirements for DWD DAR metadata generator Metadata conforms to WMO, ISO 19139 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


DWD DAR Metadata generator - architecture

XML template

Database

XSLT templates

read data

DBReader

MetaDataFileGen.

read template

1

2

WorkFacade

3processtemplate

ISO 19139 schema

4 do XSLT

5validate document

6

outputdocument

Metadata


XML template for DAR metadata

Template is ISO 19139 and INSPIRE conform

Based mainly on examples from Jürgen (DWD) and inspirations from CMA, JMA and Météo France

Nodes you may wonder about:– <gmd:hierarchyLevelName>: map navigation (theme), alternative tag <gmd:MD_TopicCategoryCode> (well-

defined by ISO, only 2 or 3 revelant entries for meteorology in enumeration)

– <gmd:descriptiveKeywords uuidref="GEMET">: we need this for INSPIRE

– <gmd:MD_SecurityConstraints>: based on April 2009 workshop with CMA we use this element for priorities of products

– <gmd:extent uuidref="BBox">: each metadata record should contain one bounding box, in addition this extent contains <gmd:temporalElement> no separate <gmd:extent> for <gmd:temporalElement> (INSPIRE)

– <gmd:dataQualityInfo>: we need this for INSPIRE


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


DAR Metadata exchange GISC to GISC

– OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting)

– Example Implementations:

• jOAI http://www.dlese.org/dds/services/joai_software.jsp

• OAICat http://www.oclc.org/research/activities/oaicat/default.htm

NC/DCPCs uploading DAR Metadata to GISC– GTS: file-naming-convention


Resources and further information IPED-MDI – Final Report

http://www.wmo.int/pages/prog/www/WDM/IPET-MDI-I/report/Report_IPETMDI_I_20100503.doc

INSPIRE Editor - http://www.inspire-geoportal.eu/InspireEditor/

INSPIRE Metadata Implementing Rules - http://inspire.jrc.ec.europa.eu/documents/Metadata/INSPIRE_MD_IR_and_ISO_v1_2_20100616.pdf


Q&A

Deutscher Wetterdienst Markus Heene, DWD [email protected] DAR Metadata.

Documents

dar metadata slide

dar metadata catalog

presentation dar metadata

dar metadata usage

metadata records

metadata record b

dar metadata record

datasets metadata record