[tz] Ambiguous abbreviations for Australian timezones when daylight savings is in affect

John Haxby john.haxby at oracle.com
Tue Apr 2 09:19:40 UTC 2013

On 02/04/13 09:30, Alan Barrett wrote:
> As long as different people can point to different web sites that say
> different things, and there is no overall summary, this matter is
> unlikely to be resolved.
> I have no decision making power here, and I have no wish to lay out a
> set of necessary conditions, but here's a stab at a set of sufficient
> conditions:
>     Provide a list of what abbreviations are actually in use by
>     the people in Australia, and what abbreviations are legislated
>     or standardised or recommended by governments or industry
>     bodies or interest groups.  If there is inconsistency,
>     then present a report on the relative frequency of use of
>     the different abbreviations.  If the report shows a clear
>     consensus in favour of one set of abbreviations, then those
>     are the abbreviations that the tz project should use.
> So far, we have identified that there is inconsistency, but I have no
> idea which abbreviations are in wider use.

I suspect that there isn't any consistency.

In the UK where we have just one timezone, commonly abbreviated to GMT
and BST depending on the time of year, we *still* have problems.   I've
had people refer to UK time as GMT regardless of the time of year (this
is especially confusing around March/April and October/November).

The man or woman on the street doesn't care about the abbreviation.
Apart from GMT (use and misuse) people usually refer to "summer time"
and "winter time", or, around the weekend of the clock change "old time"
and "new time".

In the US, it seems to be common to refer to ET and PT (Eastern,
Pacific).   I'm not a US resident, but I've seen TV trailers refer to
that quite a few times.    I also vividly recall a US manager insisting
that the time of a meeting would be 10am PST, just after the switch to
PDT.  (She insisted that it was Pacific Standard Time all year round.)

Most people don't use timezone names beyond "what time is it for Aunty
Clara in New Zealand/Canada/far-flung-country-of-choice?"   Many of
those people that really do car what time is it have multiple timezone
clocks that display a city name.

I would happily get rid of the abbreviations completely and, if an
offset needs to be expressed, use +/-HHMM.


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