[time-nuts] GMT vs. UTC

[Magnus Danielson]

From: John Ackermann N8UR <jra at febo.com>
Subject: Re: [time-nuts] GMT vs. UTC
Date: Mon, 20 Nov 2006 15:16:36 -0500
Message-ID: <45620D24.7010507 at febo.com>

> Magnus Danielson wrote:
> > Dear arch-time-nuts,
> > 
> > Today I came up with a question onto which I have no simple and quick answer in
> > the back of my head, so what is better than turning to my time-nut friends?
> > 
> > The question relates to weither GMT and UTC is the same time-scale or not.
> > If they are not, what is the difference? Where would I find any authority
> > information showing that they are the same or are not the same.
> > 
> > Now, if you would write law, which one would you use, GMT or UTC?
> > Personally, I would go for UTC (since I understand its connection to TAI).
> > GMT? I am not sure.
> > 
> > I really need to understand this issue.
> 
> Magnus, I read about this recently -- it might even have been on 
> Wikipedia -- and of course, getting old I don't recall all the details. 
>   But the short story is that, at least today, GMT has no legal or 
> official meaning.  When the term is used, it's simply a synonym for UTC.

Interstingly, this does not correlate with "Directive 2000/84/EC of the
European Parliament and of the Council of 19 January 2001 on summer-time
arrangements"

http://europa.eu.int/smartapi/cgi/sga_doc?smartapi!celexapi!prod!CELEXnumdoc&lg=EN&numdoc=32000L0084&model=guichett

in at least these translations:

http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:CS:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:ET:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:EN:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:LV:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:LT:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:HU:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:MT:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:PL:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:SK:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:FI:HTML
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:SV:HTML

Particular interest may be put into the danish translation (Poul-Henning - this
is your wakeup call!) where they refer to UTC:
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:DA:HTML

Other UTC translations are:
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:SL:HTML

Then, considering that the Swedish summertime law is indirectly refering to
UTC make me wonder, what the hell is the time at summertime? 

So, saying that GMT has no legal meaning is interesting, considering Article 7:

Member States shall bring into force the laws, regulations and administrative provisions necessary to comply with this Directive by 31 December 2001 at the latest. They shall forthwith inform the Commission thereof.

When Member States adopt those measures, they shall contain a reference to this Directive or be accompanied by such a reference on the occasion of their official publication. Member States shall determine how such reference is to be made.

Oh, and if I look up the reference and the law say UTC and the text says GMT,
how do I handle it all? If I need to transfer legal time from one country to
another, how do I do it?

This is just one of the intersting aspects I've found in laws.

Does my question start to make sense? :-)

Cheers,
Magnus