[CF-metadata] New standard name: datetime_iso8601 (standard_name or units?)

From: Jonathan Gregory <j.m.gregory>
Date: Sat, 30 Mar 2013 13:44:50 +0000

Dear all

Here's a small contribution to this large discussion!

I agree with Aleksandar and others that if we permit strings formatted in a
particular way for date-times then they should have a standard_name that
indicates they are that kind of string, and no units. That is how we treat
other string-valued quantities, which have controlled vocabularies, in
particular region and area_type. Although Steve is right that this quantity is
still time, geophysically speaking, it is functionally different.

A calendar is not needed in the string or its units if this convention is
allowed only for the real-world calendar.

I don't really like the idea of allowing such strings, myself, because of the
redundancy and potential inconsistency. I think it would need a safeguard,
that if there was a string-valued (auxiliary) coordinate variable of formatted
date-time, there had also to be a numerical coordinate variable for the same
dimension, encoded in the usual way, giving the same date-time values. Then
inconsistency could be detected. But making such a requirement seems to me to
emphasise the point that the software used to read the netCDF files ought to
be able to do this translation itself, when required.

Cheers

Jonathan
Received on Sat Mar 30 2013 - 07:44:50 GMT