On 8/27/11 5:10 AM, Lowry, Roy K. wrote:
I would suggest some fine tuning of this to:
platform_name
platform_id (note this needs to be alphanumeric to support ICES ship codes
widely used in oceanography)
platform_id_authority (mandatory if platform_id present)
platform_description
I wonder if the concept of authority is relevant to names - who is the
authority for a ship's name? Even if relevant, there is no guarantee that the
authority will be the same as the platfom_id and somebody will want to include
both a name and an id. If people feel that a name authority is required then I
would label it platform_name_authority rather than having one name doing two
jobs.
Agreed - multiple authorities are needed. Our buoys have a
platform_name conferred by OceanSITES and, usually, a WMO
platform_id as well.
Naming_authority seems to me to be especially important for ships'
names; the 'authority' could be any body that maintains, or, preferably
serves, a list of these names in a standard form. That would enable us
to e.g. equivalence R.V. Ronald H. Brown and brown.
Do we need to specify whether the _id is numeric or character? I'd prefer
to leave that to the user and his code.
The nature of the platform dscription merits a little discussion. Controlled
terms, particularly if accompanied by definitions, are always much more helpful
than plaintext. There is an internationally-governed platform type vocabulary
used in the SeaDataNet and ICES systems (http://vocab.ndg.nerc.ac.uk/list/L06).
There is also at least one relevant WMO vocabulary (VOS types).
This is another good resource; thanks, Roy.
If formalisation of the description is agreed then we could either keep
'platform_description' for plaintext and add 'platform_type' plus
'platform_type_authority' or standardise 'platform_description' by adding
'platform_description_authority'.
Finally, I think we need to agree how an authority is represented. My choice
would be a namespace URL, but maybe there are other ideas.
I'd have thought something like 'WMO' or SeaDataNet would be enough,
but ... maybe not. We really don't want to get into needing to use a
platform_id_authority_authority.
On the other hand, if it's got to be a namespace URL, I sincerely hope
it's allowed to, or required to, be human-readable. It won't go well if
my platform_id is 372224 and my platform_id_authority is a url ending
in term/P00/4/41. My CF files are written by human-generated code,
and I like the CDL files to convey meaning to humans as well.
Maybe put the URL in yet another field, platform_id_authority_reference?
Cheers - Nan
________________________________________
From: ...Jeffrey F. Painter [paint...@llnl.gov]
Sent: 27 August 2011 01:27
To: cf-metadata@cgd.ucar.edu
Subject: Re: [CF-metadata] standard names for stations
It seems to me that we would need four standard_names to satisfy
everyone's needs. How does this sound?
platform_name: variable of character type containing a character ID or
name of an observing station or other platform
platform_id: variable of integer type, identifying an observing station
or other platform
platform_naming_authority: variable of character type, specifying the
naming authority or system used to choose a platform_id or platform_name
platform_description: variable of character_type which describes an
observing station or other platform
A typical station would have a platform_name or platform_id, but rarely
both. The reason for having both is that I expect that the numerical
WMO identifiers (of various lengths) will be used very frequently, and
it can be helpful to represent numbers as numbers. But Eiji's message
shows that we must allow for character identifiers. A relatively short
character identifier would have a different function from the kind of
long description suggested by Øystein. The most common
platform_naming_authority would be the originally conceived "WMO", of
course.
- Jeff
On 8/26/11 12:36 AM, Øystein Godøy wrote:
Date: Wed, 24 Aug 2011 16:26:55 -0700
From: "Jeffrey F. Painter"<paint...@llnl.gov>
Subject: [CF-metadata] standard names for stations
To: cf-metadata<cf-metadata@cgd.ucar.edu>
Message-ID:<4e5588bf.2090...@llnl.gov>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
The draft version 1.6 of the CF Conventions manual recommends use of
two
standard names which don't exist yet but are needed to describe discrete
data such as observations from stations or other discrete points. So
I'd like to propose the following two standard names:
- station_description : variable of character type containing a
description of a time series station
- wmo_platform_id : variable of integer type, containing the WMO
identifier of an observing station or other platform
- Jeff Painter
Hi,
I clearly see the need for this.
Concerning station_description, I think this is useful whether it is a time
series or not. There is a need to describe the actual location for the
station. E.g. describe the surface, horizon, and other aspects that may affect
the observations.
Concerning wmo_platform_id, I think Nan Galbraiths suggestion using an id
and a naming authority is useful and more flexible than specifying a WMO
reference directly. Concerning my institution, all stations operated by us,
whether being WMO stations or not, always have an internal ID. Not all
stations have a WMO id. It may even be useful to be able to use multiple ids
for stations to cover situations like the one I mention.
NACCD is good but it does not have the momentum that CF has. Many other
such discovery conventions for NetCDF files exist and are used, most of
course differing only slightly. I believe they will merge in time, but for now
I think NACDD is less used than CF. I certainly agree it should be promoted
(and we will probably move towards it), but these things take time.
Thus I would prefer put as much information as possible as CF-compliant
variables in the dataset, even if it means duplicating them as global
attributes for discovery purposes.
All the best
Øystein
--
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* Nan Galbraith (508) 289-2444 *
* Upper Ocean Processes Group Mail Stop 29 *
* Woods Hole Oceanographic Institution *
* Woods Hole, MA 02543 *
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