There seems to be surprisingly broad support for this idea, so I've been
re-reading the thread, looking for a reasonable use case. I can't say that
I've found any description of why we actually need this - am I missing
something?
Anyway, going back to Aleksandar's original (slightly amended) proposal of
Jan 11 just for a moment... I'd like to clarify one detail. As far as
I know,
ISO 8601 calls for the default time zone to be local, not UTC.
If we're going to add this option to CF, we should *at least* require
the time
zone to be specified. Allowing a default, and having that default NOT align
with ISO, is just too much to ask. Either we're implementing ISO, or not -
changing the default meaning of the time zone would truly mislead our
imaginary post-apocalyptic researchers - and I know how much we all
worry about them.
From Wikipedia (my only available ISO documentation):
/Time zones in ISO 8601 are represented as local time (with the location //
//unspecified), as UTC, or as an offset from UTC.//
//If no UTC relation information is given with a time representation, the //
//time is assumed to be in local time. /
Cheers - Nan
On 1/11/13 12:00 PM, Aleksandar Jelenak - NOAA Affiliate wrote:
> Dear All:
>
> Here's the modified proposal for the datetime_iso8601 standard name:
>
> standard_name: datetime_iso8601
>
> Units: N/A
>
> String representing date-time information according to the ISO
> 8601:2004(E) standard. Variables with this standard name cannot serve
> as coordinate variables. Date-time information is in the Gregorian
> calendar. For dates preceding the Gregorian calendar the date-time
> information is in the proleptic Gregorian calendar. Possible date-time
> string forms are:
>
> <datetime> = <date> "T" <time> <timezone> ;
>
> <date> = YYYY "-" MM "-" DD | YYYY "-" DDD ;
>
> <time> = hh | hh ":" mm | hh ":" mm ":" ss | hh ":" mm ":" ss "." S
> | hh ":" mm ":" ss "," S ;
>
> <timezone> = "" | "Z" | "+" hh | "+" hh ":" mm | "-" hh | "-" hh ":" mm
>
> Where:
>
> * "YYYY" is a four-digit year (0000-9999).
> * "MM" is a two-digit month of the year (01-12).
> * "DD" is a two-digit day of the month (01-31).
> * "DDD" is a three-digit ordinal day of the year (001-366).
> * "hh" is a two-digit hour (00-23).
> * "mm" is a two-digit minute (00-59)
> * "ss" is a two-digit second (00-60).
> * "S" is one or more digits representing a decimal fraction of the
> second.
>
> * The value of any designator when not specified is zero.
>
> * If <timezone> is ommitted the default value is "Z".
>
--
*******************************************************
* Nan Galbraith Information Systems Specialist *
* Upper Ocean Processes Group Mail Stop 29 *
* Woods Hole Oceanographic Institution *
* Woods Hole, MA 02543 (508) 289-2444 *
*******************************************************
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Received on Tue Mar 19 2013 - 13:08:57 GMT
