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)
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: Aviemore Location (deg lat, deg long): 57N, 3W Elevation: 226m Parameter observed: temperature Operator: Met Office Started: 11:50 01/01/01 Ended: 12:00 01/01/01 Value: 4 Units: Celsius Instrument instrument number: 123456 instrument inspection date: 01/01/01 instrument 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 metadata WMO specifics Topic ISO standard: climatology, meteorology, atmosphere, environment, oceans add: list of more specific topics Keywords add: define list of standard physical quantities
WMO Core Metadata WMO specifics Space add: Irregular point set Time add: 360 day calendar
WMO Core metadata Status 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 metadata Status XML –practical method of exchanging information –schemas written and tested but now ISO standard agreed
WMO Core metadata Status Discover Temperature in Sweden? Stockholm, please Select Retrieve
WMO Core Metadata Status Features –describe actual data 211620Z EGLL EGLL 211620Z 19007KT 170V230 9999 FEW038 BKN060 20/11 Q1020 NOSIG
WMO Core metadata Status 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