Re: [CF-metadata] Request for standard names: sea ice age and fraction of first year ice
Dear Laurent, Bruce, Jonathan, and all, May I step in? Laurent expresses a need for new standard names related to sea ice type, from a modellers point of view. I would like to take the opportunity to also discuss standard names for such quantities, but from a satellite observation point of view. The reason I step-in, and not start a new discussion is because I guess both Laurent and I will use the same definition of what is first-year-ice (by opposition to multi-year-ice). The way we use these definitions to build our gridded products is, however, different. Some satellite products we distribute via the MyOcean project (SIW TAC) are observations of sea ice types. However, unlike what Laurent's model computes, the satellite product is a classification where each non-land pixel in the grid is either open_water, first_year_ice, multi_year_ice, or ambiguous. The latter is for cases where we do not feel confident for deciding if the (ice) grid cell is first- or multi- year ice. In essence, the satellite product is a classification, very similar to e.g. a land-cover product, where each cell contains a code, that code corresponds to a class (with associated label and definition). All classes are exclusive from all others. In my case (sea ice type classification), I wonder: 1) if an appropriate standard name could be sea_ice_type_classification. 2) Do you have previous experience with 'classifications' in CF? 3) if my 'classification' could re-use (in a more generic way) the structure of CF 'flags', with flag_values, flag_masks and flag_meanings. Since my data would be a 'sea ice type classification' (and not 'flags'), I would fancy using 'sea_ice_type_values', and 'sea_ice_type_meanings' (I would not use 'sea_ice_type_masks'). In the case of Laurent, Jonathan proposes: first_year_sea_ice_area_fraction The main point here, is probably to agree if the variable holds a first year ice fraction of total ice concentration, or a concentration of first year ice (first year ice fraction of total cell area): first_year_sea_ice_area_fraction + multi_year_sea_ice_area_fraction = sea_ice_area_fraction or first_year_sea_ice_fraction * sea_ice_area_fraction = firt_year_sea_ice_area_fraction and multi_year_sea_ice_fraction * sea_ice_area_fraction = multi_year_sea_ice_area_fraction (first_year_sea_ice_fraction + multi_year_sea_ice_fraction = 1) Concerning the discussion if the standard name should define first year sea ice age only (always less than... 1 year!), or the age of sea ice (from 0 to X years), I guess both standard names will proove handy in the end. Fowler et al (at NSIDC) deliver a sea ice age product, based on sea ice motion estimates from satellites. Their gridded values are from 0 to 3 or 4 years, as far as I remember. I hope this helps, and does not broaden too much the focus of Laurent's original request. We can start a different thread on CF generic classifications if you deem it more appropriate. All the best, Thomas ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
Re: [CF-metadata] WS querying cf meta data catalog
Dear Uwe, It exists. A copy of the Standard Names is served through the NERC Vocabulary Server (http://www.bodc.ac.uk/products/web_services/vocab/). The references to the Standard Names list are: Live terms: http://vocab.ndg.nerc.ac.uk/list/P071/current/ Deprecated terms: http://vocab.ndg.nerc.ac.uk/list/P072/current/ These list addresses may be incorporated into either the SOAP or HTTP-POX APIs described in the URL reference above. Individual Standard Names are addressed through BODC-assigned opaque identifiers such as: http://vocab.ndg.nerc.ac.uk/term/P072/17/CFSN0012 The associated canonical units will be found in references containing 'P061' in the mappings section of the payload XML document, such as skos:minorMatch rdf:resource=http://vocab.ndg.nerc.ac.uk/term/P061/37/KMP2; /. The Standard Name list is also maintained in the MMI Ontology Registry and Repository which again provides programmatic access through an API. I'll leave it to the MMI folks to provide you with pointers to the detail. Cheers, Roy. -Original Message- From: cf-metadata-boun...@cgd.ucar.edu [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of Uwe Rosebrock Sent: 26 May 2011 00:41 To: cf-metadata@cgd.ucar.edu Subject: [CF-metadata] WS querying cf meta data catalog Hi all, is there or is there a plan to establish a web service to query the standard_name list and units programatically (without human interaction)? would such a service be useful as vocabulary by anybody? Cheers Uwe ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata -- This message (and any attachments) is for the recipient only. NERC is subject to the Freedom of Information Act 2000 and the contents of this email and any reply you make may be disclosed by NERC unless it is exempt from release under the Act. Any material supplied to NERC may be stored in an electronic records management system. ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
[CF-metadata] CF Metadata - CF Convention 1.5
Hi, Having recently taken up an appointment that involves me working with meteorological/ocenographic datasets I have been reading the CF Conventions documentation. I've noted that the documention, when refering to the units variable attribute, references UNIDATA's udunits package and the data file udunits.dat. This data file appears to relate specifically to v1.12.11 of the udunits package, while I note that the current release is v2.1.23. Does the CF Convention only recognise unit values listed in v1.12.11 or is it meant to encompass v2.1.23 as well. Note: I have not determined if there are any differences in the units database between v.1.12.11 and v2.1.23. Kind regards, Glenn Comiskey Data System Administrator Fugro Global Environment Ocean Sciences Fugro House, Hithercroft Road Wallingford, Oxfordshire OX10 9RB, UK Registration No: 2985431 / VAT No: GB 655475606 Tel: +44 (0) 1491 820500 (Switchboard) / Tel: +44 (0) 1491 820559 (Direct) / Fax: +44 (0) 1491 820599 E-mail: g.comis...@geos.com mailto:g.comiskey@g.comis...@geos.com / Website: www.geos.com http://www.geos.com/ Please note: * The information contained in this message is privileged and confidential and intended only for the use of the addresses. If you are not the intended recipient you should not read, copy, distribute or otherwise use the information; * Fugro Global Environment Ocean Sciences accepts no responsibility for loss or damage of any kind arising from the use of this message; * If you have received this message in error, please note the sender immediately and delete the message. ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
Re: [CF-metadata] WS querying cf meta data catalog
Dear Uwe: You can look here: http://marinemetadata.org/orrcf for information about using our representation of the CF Standard Names and example related queries. Carlos On Thu, May 26, 2011 at 1:20 AM, Lowry, Roy K. r...@bodc.ac.uk wrote: Dear Uwe, It exists. A copy of the Standard Names is served through the NERC Vocabulary Server (http://www.bodc.ac.uk/products/web_services/vocab/). The references to the Standard Names list are: Live terms: http://vocab.ndg.nerc.ac.uk/list/P071/current/ Deprecated terms: http://vocab.ndg.nerc.ac.uk/list/P072/current/ These list addresses may be incorporated into either the SOAP or HTTP-POX APIs described in the URL reference above. Individual Standard Names are addressed through BODC-assigned opaque identifiers such as: http://vocab.ndg.nerc.ac.uk/term/P072/17/CFSN0012 The associated canonical units will be found in references containing 'P061' in the mappings section of the payload XML document, such as skos:minorMatch rdf:resource= http://vocab.ndg.nerc.ac.uk/term/P061/37/KMP2; /. The Standard Name list is also maintained in the MMI Ontology Registry and Repository which again provides programmatic access through an API. I'll leave it to the MMI folks to provide you with pointers to the detail. Cheers, Roy. -Original Message- From: cf-metadata-boun...@cgd.ucar.edu [mailto: cf-metadata-boun...@cgd.ucar.edu] On Behalf Of Uwe Rosebrock Sent: 26 May 2011 00:41 To: cf-metadata@cgd.ucar.edu Subject: [CF-metadata] WS querying cf meta data catalog Hi all, is there or is there a plan to establish a web service to query the standard_name list and units programatically (without human interaction)? would such a service be useful as vocabulary by anybody? Cheers Uwe ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata -- This message (and any attachments) is for the recipient only. NERC is subject to the Freedom of Information Act 2000 and the contents of this email and any reply you make may be disclosed by NERC unless it is exempt from release under the Act. Any material supplied to NERC may be stored in an electronic records management system. ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata -- Carlos A. Rueda, PhD MMI Technical Lead - marinemetadata.org caru...@mbari.org - 831-775-1929 Monterey Bay Aquarium Research Institute - mbari.org ___ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
