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

Timothy Arceri t.arceri at bom.gov.au
Sun Mar 31 11:16:40 UTC 2013

Tobias Conradi <tobias.conradi <at> gmail.com> writes:


First off I would like to thank all the people giving me their support on this
issue. There have been some very good arguments in support of my suggestion, I'm
glad to at least see a good discussion on the problem. I would just like to say
I'm yet to see any convincing argument for keeping the status quo vs updating
the database. In following post I attempt to address all the arguments against
so far.

RE: Paul Eggert

>I'm afraid that doesn't follow.  One can easily find disagreements
>with the contents of those links.  For example, you gave a link to the
>NSW Dept of Attorney General & Justice saying that in summer, eastern time
>is abbreviated "AEDT".  But that very web page also says, in another
>place, that the abbreviation is "EDST".  So this single source contradicts
>the assertion that abbreviations are consistently used by the NSW
No ii says “Daylight saving or summer time is commonly expressed as EDST”. My
name is commonly expressed as Tim Arceri. But my name is Timothy Arceri. It
clearly uses AEST/AEDT as the correct abbreviations.

RE: Robert Elz

>The general public don't care - they just want to know what time according
>to the clock on the wall things happen - local time - and that's all you
>ever need to tell them.

This is a simplistic and naive view especially when daylight savings is involved
as the clock on the wall is not always correct. For example not everyone
remembers to update their clock on the change over of daylight savings time.
With an emergency warning systems its our job to be as precise as possible as to
remove any potential confusion. Another example is a person in NSW ringing up
their family in QLD during daylight savings to warn them of a tsunami. They may
look at the time of arrival for a QLD location and tell their family that they
have 2 hours before the tsunami arrives but in fact it is only 1 hour as they
forgot to apply the daylight savings difference. Yes they may forget anyway but
by using EST/EDT we have at least given them all the information they need.

>If you were actually doing what you're suggesting that you're doing then
>you (or your organisation) ought to be prosecuted for criminal negligence
>(or something like that).    That is, you're suggesting that you're going
>to tell people that a Tsunami might arrive at 10:45 EST, and that will
>cause confusion because EST means different things in NSW and Qld.

Please read things properly before insulting someone I clearly said we need a
custom script to make EST/EDT abbreviations. Your argument above actually
supports the updating of abbreviations.

>You might not care much about the confusion between (Aust) EST and
>North American EST (and others between the different ISTs and JSTs and ...)
>but the people for whom timezone management really does matter do.
>For them, our abbreviations are useless, they either use their own
>identifying system, or numeric offsets - nothing we do can possibly
>solve their problems while simultaneously allowing the abbreviations to
>be used the way you apparently want to use them.

In your whole post you have mentioned not a single reason why its better to keep
the current abbreviations rather than updating them with my suggestions (unless
you count the fact you wish people didn't use them, but they do). But you have
yourself mentioned twice how the current abbreviations cause confusion. 

RE: Curtis Manwaring 

>Because we don't want to work ourselves to death with constant changes. 
>Someone will complain that we caved and will insist on changing it back to 
>what it was before or someone else will come in and say it was changed the 
>wrong way.  Until there is an agreed upon standard there will be no 
>stability; so to not change is the best move.  When everybody in Australia 
>comes to an agreement on what those abbreviations should be, let us know.
As I've already mentioned the current abbreviation used by the database EST
(Eastern Summer Time) is used by no one in Australia all I'm asking is that you
at least use something that is recognised and I think I've made a fairly decent
attempt are proving there are generally accepted abbreviations used by the state
Or as was very well put by David Patte: 
>I think its quite clear what the most common standard is. AEST / AEDT 
>(and likewise westward) are the national standards. It is also a clear 
>and unambiguous selection for those unfamiliar with local custom, and to 
>the majority of Australians that come to this list.

>And to finally clarify it and put it everything in perspective, the site 
>from the communityrelations.lawlink says the standards follow the above 
>rules, though "summer time is commonly expressed as EDST".

>When the approved standard is as in my first line, but a common usage is 
>often "EDST", then you go with the goverment standard, not the common 
>usage. This is not the USA we are talking about here - its Australia, 
>where its citizens tend to somewhat respect the national laws and 
>standards used by the government they have voted for.

>Are people suggesting we should go with Daylight Saving's' time (which 
>is the 'common expression' in many parts of the USA) when the standard 
>is Daylight Saving (no 's') time? Or worse yet, when some people use 
>one, and some the other - we should then impose a third ambiguous 
>expression upon users of our database, as we are doing now?

>I'm tired of this debate, as we all are, but clearly the noise can 
>reduced by using the AEST/AEDT (and like) abbreviations over what is 
>defined now.

>It clearly states on one of the examples presented that the Australian 
>standard is as above but in some calles
>It is difficult for tell what is current usage (e.g. see the first two links).
 >If the Australian government thinks that it is important to stop the confusion
>it would likely find an effective way to convince the people in Australia about
>that.  I don't think that it is a good idea for the Olson database to dictate
>what the people within Australian should do.
Every link you have posted uses the daylight savings abbreviations I'm asking
for. Yes the use of a beginning A is seen as somewhat optional (but I don't
think anyone would have any objections to its use ) but the daylight savings use
of D is consistent. As mentioned above the Olson database is already dictating
we use EST (Eastern Summer Time) when no one in Australia does.
RE: Clive D.W. Feather
>So if we did change them to a new set, we could well end up getting the
>same argument again, but this time the CWT etc. people would be complaining
>and filling up my mailbox while the AEZT people would be saying "there
>isn't consensus - no need to change it".

CWT - Is a separate time zone and is separate issue to the change I'm suggesting
. I'm not sure if that database currently supports it but I believe it does not
in which case there is no reason they would not be filling up your mailbox
anyway. If it is supported then it can possibly be left as is even with the
suggested changes although as far as I'm aware this is an unofficial time zone.
AEZT – What is this? 

Also as Tobias Conradi pointed out:
>The proposal made by Timothy is not to just change to a /new/ set, but to a set
>that lets users differentiate between different offsets by the acronym.

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