WMO Core Metadata
Dr Steve Foreman
Chair, Inter-Programme Expert Team on Metadata Implementation
Contents
• Data challenges facing meteorology
• What is “metadata”?
• WMO approach to metadata
• Implementation of the standards
Challenges facing WMO
Regional Associations
R.A. IR.A. IAfricaAfrica(56 Members(56 Members))
R.A.IIIR.A.IIISouth AmericaSouth America(13 Members)(13 Members)
R.A. VR.A. VSouth-West PacificSouth-West Pacific(22 Members)(22 Members)
R.A. VIR.A. VIEuropeEurope(49 Members)(49 Members)
R.A. IVR.A. IVNorth North America, America, Central Central AmericaAmericaAnd the And the CaribbeanCaribbean(25 (25 Members)Members)
R.A. IIR.A. IIAsiaAsia(35 Members)(35 Members)
Challenges for WMO Technical Commissions
Basic Commissions
Commission for Basic Systems (CBS)
Commission for Instruments and Methods of Observations (CIMO)
Commission for Hydrology (CHy)
Commission for Atmospheric Sciences (CAS)
Applications Commissions
Commission for Aeronautical Meteorology (CAeM)
Commission for Agricultural Meteorology (CAgM)
Joint WMO/IOC technical Commission for Oceanography and Marine Meteorology (JCOMM)
Commission for Climatology (CCl)
Challenges for WMO
Weather forecast
23 400 000
Surface temperature
3 050 000
Climate change
67 600 000
Hurricane warning
375 000
What is metadata?
• “Data about data”– describes data
• what are the data?• where are they for?• who is responsible?• what are the units?• ………..
What is metadata?
• In this context it is not– the conditions at an observing site
• although– these can be described by metadata
What is metadata?
Observing site name: AviemoreLocation (deg lat, deg long): 57N, 3WElevation: 226mParameter observed: temperatureOperator: Met OfficeStarted: 11:50 01/01/01Ended: 12:00 01/01/01
Value: 4Units: CelsiusInstrument
instrument number: 123456instrument inspection date: 01/01/01instrument type: Magic mercury 1234
Data
Metadata
What is metadata?
• Need to agree– what needs to be described– how they will be organised– what they will be called
• So that– non-specialists can find data– applications can handle data
WMO approach to metadata
• Build on existing standards– WMO
• GRIB and BUFR definitions
– ISO• 191xx series
– Geographic metadata (19115) – XML representation (19139) ?
– Open Geospatial Consortium
• Catalog service ?
WMO Core metadata
• Use ISO 19115– international standard
• evolving• lessons from other users
• Complex– select subset– expand where essential
• but can cause problems for others
WMO Core Metadata
• Core metadata:– subset of full standard– most appropriate elements for field– some extensions to cover specific needs
• Contents of Core:– Mandatory: required either by ISO standard
or by Core– Optional: elements expected to be
included, but not always applicable
WMO Core metadata - overview
About metadata
Metadata standard
Language
Maintenance
Dataset details
Title of dataset
Description (abstract), topics covered
Where data are, format
Time and space
Representative:
Area/volume covered by data
Time span for data
IPR issues
Owner and contact
Restrictions on use
Data types
Physical quantities, units, specific qualities
Quality control and processing information
WMO Core metadataWMO specifics
• TopicISO standard: climatology, meteorology,
atmosphere, environment, oceans
add: list of more specific topics
• Keywordsadd: define list of standard physical quantities
WMO Core MetadataWMO specifics
• Spaceadd: Irregular point set
• Timeadd: 360 day calendar
WMO Core metadataStatus
• Draft standard– presented to CBS XIII– available for testing
• does it cover needs of Programmes?• are all the extensions needed?• is it too biased to World Weather Watch?
WMO Core metadataStatus
• XML– practical method of exchanging information– schemas written and tested
• but now ISO standard agreed
WMO Core metadataStatus
Discover
Temperature in Sweden?
Stockholm,please
Select
Retrieve
WMO Core MetadataStatus
• Features– describe actual data
211620Z EGLL EGLL 211620Z 19007KT 170V230 9999 FEW038 BKN060 20/11 Q1020 NOSIG
WMO Core metadataStatus
• Tests:– Russian climatology– SIMDAT data supply– ACSYS polar information
Implementation
• Technical– define features– review standard
• ISO changes• extensions needed?• what in “metadata”, what in “features”?
– apply new standards• XML representation• Open Geospatial Consortium catalogues
Implementation
• Testing– needs of other Programmes– interoperability
• Processes– maintenance
• Core Profile• Catalogues• Lexicons• etc….
Summary
• Metadata– increase usefulness of data
• WMO Core– description available to all
• Implementation– test for non-World Weather Watch– XmL representation– feature definition– tools