John raises some good points, which I think are apropos of the fact that
a set of terms for area_type will probably have to be more comprehensive
than what are currently in use in CF for cell_methods use. Maybe I'm
assuming that this was the original idea behind the list (for cell
methods),
because that's what ticket 17 is about.
It seems like it's worth it to try to create a reasonably complete list
of area
types, though, if one doesn't exist already, since it could be useful in
different contexts (i.e. for observational data). It will probably be used
beyond the original intended purpose, in any case.
I'm also confused by one additional item that hasn't been mentioned yet.
Does the fact of the 'ice_free_sea' area type imply that plain 'sea'
has ice?
Or is 'sea' just a less definitive term that may or may not have ice? This
might be clear in cell methods use, but it would be confusing in more
general
uses of this kind of list.
Also, I could not find a discussion of the difference between
floating_ice and
sea_ice in ticket 17. If one of these terms excludes icebergs by common
usage
in the modeling community, I'm not aware of the convention.
Cheers - Nan
> I have a few suggestions for the area_type info. Well, more like
> questions.
>
> An area_type that I imagine being useful within a year or two, if not
> within months, is the benthic floor (i.e., land under the sea). And
> by analog: land under a lake, or the more general
> water_covered_ground. I'm not recommending those changes now, but they
> raise the following question: Is 'land' is intended to be
> all-encompassing in this regard? Definitions would help make this
> clear. As a general observation, discussing terms without associated
> definitions can lead to confusion on all parts.
>
> I don't see how all_standard_names makes sense as an area_type.
>
> If lake_ice_or_sea_ice excludes icebergs, does sea_ice? This is
> counterintuitive to a lay person, admittedly not the target audience.
> (Also note, this is where the relation between terms is useful
> information to have -- somewhere in my assumed hierarchy
> floating_ice
> lake_ice_or_sea_ice
> sea_ice
> there is a discrepancy, perhaps intentional. Suggest the discontinuity
> be made explicit in the definition (i..e, explain why
> lake_ice_or_sea_ice excludes icebergs, while floating_ice does not;
> and address whether sea_ice includes icebergs. The definition is
> where people will look to understand the relationships.
>
> I assume the absence of lake_ice is deliberate. (Just a thought:
> Sometimes completeness is helpful for clarity, especially when there
> are no definitions, even though there may not be any immediate use for
> the term. Otherwise it makes some of us wonder why something *wasn't*
> included.)
>
>
> John
>
>
>
>
>
> On Dec 4, 2008, at 6:03 AM, Pamment, JA (Alison) wrote:
>
>> Dear All,
>>
>> Velimir and I have been working on creating the new table of
>> standardized area_type strings as agreed under trac ticket 17. The
>> table lists the values permitted in variables with a standard_name of
>> area_type. To view version 1 of the table please go to
>> http://cf-pcmdi.llnl.gov/documents/cf-standard-names/area-type-table/cur
>> rent/area-type-table. Clicking on the individual table entries will
>> reveal explanatory text, although currently there is only help available
>> for the two new floating_ice strings. Please let us know if you have
>> any comments about the format of the table.
>>
>> For ease of reference, there is also now a link from the area_type
>> description text in the html version of the standard_name table to the
>> new area_type table.
>>
>> At the top of the standard name table a link has been created to the
>> standard name Guidelines document. This has been done with the
>> intention of giving greater prominence on the website to the existence
>> of the Guidelines.
>>
>> The html copy of the standard name table has been rebuilt to add the new
>> links, but this in no way affects the contents of the table which
>> remains at version 11. There are no changes to the xml version of the
>> table.
>>
>> Velimir has converted the standard name Guidelines document to the
>> docbook format (similar to the conventions document) and this hopefully
>> will make it more navigable. In addition, we have introduced version
>> numbering of the Guidelines. This is in response to the fact that there
>> has been a number of recent changes to the document and it looks likely
>> that there will be more in the future. The Guidelines are currently at
>> version 1 and this number will be incremented each time a change is
>> made.
>>
>> If you have any comments regarding any of the above, please send them to
>> the list.
>>
>> Best wishes,
>> Alison
>>
>> ==> Please note new email address: alison.pamment at stfc.ac.uk <==
>>
--
*******************************************************
* Nan Galbraith (508) 289-2444 *
* Upper Ocean Processes Group Mail Stop 29 *
* Woods Hole Oceanographic Institution *
* Woods Hole, MA 02543 *
*******************************************************
Received on Fri Dec 05 2008 - 08:05:53 GMT
