So I may be missing the mark, but I see Martin's request as being about 
encoding ISO-compatible data into NetCDF files, whereas at first glance the 
NOAA/Unidata work appears to be about transforming pure NetCDF data/metadata 
into ISO format. 

It seems to me a fundamental question is whether you want to encode a complete 
ISO file as a single text attribute, or ISO attributes as NetCDF attributes 
using a standard transformation. Either could be done systematically.  An 
entire file will gracefully interoperate with ISO tools with very little 
further negotation about the standard way to go back and forth; but will be 
relatively opaque with plain netCDF tools. An attribute-based approach will 
require a bit more thought and specification up front, but will give you 
independent netCDF attributes which might be more easily viewable in a strictly 
netCDF context. (Of course, all those attributes could bury the native 
attributes.)

In OOI's CI software we may want to capture ISO metadata in the Common Data 
Model, so the resolution of this question will be of some interest.

John

On Feb 21, 2011, at 04:27, Rich Signell wrote:

> Martin,
> 
> Ted Habermann & Dave Neufeld at NOAA and Ethan Davis at Unidata have been 
> making great strides in this department.    I'm sure they'll chime in with 
> more info, but to get going, check this out:
> 
> https://geo-ide.noaa.gov/wiki/index.php?title=NcISO
> 
> -Rich
> 
> On Mon, Feb 21, 2011 at 5:52 AM, Schultz, Martin <[email protected]> 
> wrote:
> Dear all,
> 
>    after searching the mailing list archive without success, I would like to 
> bring up the topic of the ISO19115 metadata standard for geographical 
> information and how to best map this into CF. Obviously, the ISO standard 
> builds on XML and its hierarchical structures, while (global) attributes in 
> netcdf files are "flat". While "professional" applications can organize 
> databases and maintain proper links between metadata information in XML files 
> and data in netcdf files, the normal user risks loosing a lot of metadata 
> information if he relies solely on the content of the file. All that CF1.5 
> lists for the "Description of file contents" is:
> 
> "
> title:    A succinct description of what is in the dataset.
> institution:    Specifies where the original data was produced.
> source:    The method of production of the original data. [...]
> history:    Provides an audit trail for modifications to the original data. 
> [...]
> references:  Published or web-based references that describe the data or 
> methods used to produce it.
> comment:    Miscellaneous information about the data or methods used to 
> produce it.
> "
> 
> As an example of the level of detail ISO19115 defines, here is an excerpt 
> from http://eden.ign.fr/xsd/isotc211/isofull/20090316/gmd/citation.xsd/view:
> 
> <xs:complexType name="CI_Citation_Type">
>                <xs:annotation>
>                        <xs:documentation>Standardized resource 
> reference</xs:documentation>
>                </xs:annotation>
>                <xs:complexContent>
>                        <xs:extension base="gco:AbstractObject_Type">
>                                <xs:sequence>
>                                        <xs:element name="title" 
> type="gco:CharacterString_PropertyType"/>
>                                        <xs:element name="alternateTitle" 
> type="gco:CharacterString_PropertyType" minOccurs="0" maxOccurs="unbounded"/>
>                                        <xs:element name="date" 
> type="gmd:CI_Date_PropertyType" maxOccurs="unbounded"/>
>                                        <xs:element name="edition" 
> type="gco:CharacterString_PropertyType" minOccurs="0"/>
>                                        <xs:element name="editionDate" 
> type="gco:Date_PropertyType" minOccurs="0"/>
>                                        <xs:element name="identifier" 
> type="gmd:MD_Identifier_PropertyType" minOccurs="0" maxOccurs="unbounded"/>
>                                        <xs:element 
> name="citedResponsibleParty" type="gmd:CI_ResponsibleParty_PropertyType" 
> minOccurs="0" maxOccurs="unbounded"/>
>                                        <xs:element name="presentationForm" 
> type="gmd:CI_PresentationFormCode_PropertyType" minOccurs="0" 
> maxOccurs="unbounded"/>
>                                        <xs:element name="series" 
> type="gmd:CI_Series_PropertyType" minOccurs="0"/>
>                                        <xs:element 
> name="otherCitationDetails" type="gco:CharacterString_PropertyType" 
> minOccurs="0"/>
>                                        <xs:element name="collectiveTitle" 
> type="gco:CharacterString_PropertyType" minOccurs="0"/>
>                                        <xs:element name="ISBN" 
> type="gco:CharacterString_PropertyType" minOccurs="0"/>
>                                        <xs:element name="ISSN" 
> type="gco:CharacterString_PropertyType" minOccurs="0"/>
>                                </xs:sequence>
>                        </xs:extension>
>                </xs:complexContent>
>        </xs:complexType>
> 
> I believe it would be nice if these two worlds could be better connected. 
> Obviously, an easy way would be via URI (for example in a global attribute 
> called iso19115 which would point to a location where the XML file can be 
> obtained). However, this is rather fragile and it would be nice to save the 
> extended metadata information in the file itself. One way could be an 
> attribute named xml (either global or variable attribute(s)" which would 
> contain XML text - this text could then identify itself as being ISO19115 
> compliant, for example. A virtue of such a concept would be that automated 
> data servers could insert the "external" metadata information in the file 
> upon delivery. Since the present attributes to describe the file content are 
> optional anyway, CF wouldn't need to be modified much, except for mentioning 
> the xml attribute and its purpose.
> 
> If there are other ways to integrate ISO19115 and CF which have proven 
> efficient in practice, I'd be happy to learn about them.
> 
> Best regards,
> 
> Martin Schultz
> 
> = Dr. Martin G. Schultz, IEK-8, Forschungszentrum Jülich  =
> = D-52425 Jülich, Germany                                 =
> = ph: +49 (0)2461 61 2831, fax: +49 (0)2461 61 8131       =
> = email: [email protected]                          =
> = web: http://www.fz-juelich.de/icg/icg-2/m_schultz       =
> 
> 
> ------------------------------------------------------------------------------------------------
> ------------------------------------------------------------------------------------------------
> Forschungszentrum Juelich GmbH
> 52425 Juelich
> Sitz der Gesellschaft: Juelich
> Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498
> Vorsitzender des Aufsichtsrats: MinDirig Dr. Karl Eugen Huthmacher
> Geschaeftsfuehrung: Prof. Dr. Achim Bachem (Vorsitzender),
> Dr. Ulrich Krafft (stellv. Vorsitzender), Prof. Dr.-Ing. Harald Bolt,
> Prof. Dr. Sebastian M. Schmidt
> ------------------------------------------------------------------------------------------------
> ------------------------------------------------------------------------------------------------
> _______________________________________________
> CF-metadata mailing list
> [email protected]
> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
> 
> 
> 
> -- 
> Dr. Richard P. Signell   (508) 457-2229
> USGS, 384 Woods Hole Rd.   
> Woods Hole, MA 02543-1598
> 
> _______________________________________________
> CF-metadata mailing list
> [email protected]
> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata



John Graybeal   <mailto:[email protected]> 
phone: 858-534-2162
Product Manager
Ocean Observatories Initiative Cyberinfrastructure Project: 
http://ci.oceanobservatories.org
Marine Metadata Interoperability Project: http://marinemetadata.org   

_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata

Reply via email to