Alison Pamment CF Standard Names Status and Development Alison Pamment

Overview  Current status of CF standard name table  Process for agreeing standard names  Development needs

Current Status  Currently 1039 names in table  Represents approx 30% increase in size of table over 12 months  A further 40 proposed names are agreed and ~30 are currently under discussion

Standard Name Process (1)  All proposals for new standard names must be made via the CF-Metadata mailing list  There are published guidelines for the construction of standard names  Proposals should include the unit and a definition

Standard Name Process (2)  Discussion of proposals takes place on the mailing list and all may participate  The aim is to achieve consensus  The standard names manager acts as moderator and keeps the discussion moving forwards

Standard Name Process (3)  Names for which consensus has been achieved are flagged as ‘accepted’ by the moderator  Accepted names will go into the table at the next bimonthly update  Accepted names can be used immediately – don’t have to wait for table update to take place

Standard Name Process (4)  Where consensus cannot be reached by discussion the moderator will ask the standard names committee to vote on the proposed names  The committee’s decision will be final  All versions of the standard name table and guidelines will be kept online

Development Needs – the problem  Many standard name proposals are pretty straightforward… BUT  A minority of name proposals are controversial and raise more questions than they answer FOR EXAMPLE:  For new name proposals how much weight should be given to current usage in communities beyond CF?

Development Needs – the problem  Should we use human readable strings or opaque URIs that point to a definition?  Should we put the definition in the file?  Are standard names too long to be useful?  We need a standard names ‘philosophy’

Standard Name Philosophy  Are the names aimed primarily at the proposing community or to be easily understood by the whole CF community?  Human readable names certainly shouldn’t be misleading  CF standard names can never be all things to all people

Development Needs  How do we express the relationship between CF standard names and external vocabularies?  Currently we have GRIB and AMIP equivalences but they are out of date  NDG vocabulary server  Tickets … : ‘common_concept’

Common_concept  The proposal is to allow a ‘bundling’ of CF metadata to include standard_name + other attributes, e.g, 2m temperature  The ‘bundle’ could consist of a standard_name alone  The bundle would have a scoped name and a URI that points to its definition  Need a way of defining the constraints on a common_concept definition (#29)  The URI could point to metadata not defined in CF (#27)

Common_concept  Registration of a common_concept would be quick (automated)  Another user could register a different scoped name for an existing common_concept but the URI would be identical  Common_concept would facilitate:  The creation of short names  Translation between standard_names and other vocabs

Other Development Needs  Instrument information – should it go in the standard name?  Chemistry names (IUPAC?)  Ticket 17: use cell_methods instead of ‘where’ names  Ticket 33: ‘count over days’ for use with standard names for climate statistics

Summary  Agreed rules for standard names proposals will be published on CF website  We need to develop a clear standard names ‘philosophy’  The common_concept idea has received unanimous support in principle – there is much work to do on the practical implementation