[tz] Propose new zone for Crozet Islands

Tobias Conradi tobias.conradi at gmail.com
Thu May 24 07:46:59 UTC 2012

On Thu, May 24, 2012 at 4:52 AM, Tobias Conradi
<tobias.conradi at gmail.com> wrote:
> On Wed, May 23, 2012 at 7:09 PM, Antoine Leca <Antoine-TZ at leca-marti.org> wrote:
>> I have no information whether the clocks might have been different from
>> the "natural" UTC+4 time zone (which extends up to 52°W 30') at any
>> moment in the past (long-timers and archivists may record unclear and
>> unchecked informations this about in 1986); so the correct move seems to
>> create a new zone, perhaps along the attached changes (AFT is my
>> invention, anything better will be fine with me;
> TFT, according to widespread use of "<ISO 3166-1 alpha-2>T"
Withdraw TFT, since with the proposal there are two zones for TF.

ftp://ftp.iana.org/tz/data/antarctica gives
Indian/Kerguelen ... TFT
so TFT is ambiguous there too.

The AFT mentioned by Antoine is used for Afghanistan says

Fixing the data proposed for zone.tab, using coordinates from
ftp://ftp.iana.org/tz/data/antarctica for Crozet Islands:
TF    -492110+0701303 Indian/Kerguelen most locations
TF    -462551+0515152 Indian/Alfred-Faure Crozet Islands

So maybe for
Crozet Islands and Kerguelen Islands
TFWT and TFET (West/East)
can be used.

I would prefer TFCT and TFKT, which are based on toponyms.

But ftp://ftp.iana.org/tz/code/Theory says
"When a country has multiple time zones, take the first three
letters of an English place name identifying each zone
and then append `T', `ST', etc. as before;
e.g. `VLAST' for VLAdivostok Summer Time."

which would lead to:
AFBT - Alfred-Faure Base (Crozet)
PAFT - Port-aux-Francais (Kerguelen)

The rule in the Theory file can easier lead to double assignments of
abbreviations, since
a) there seems to be no list in the source code for all abbreviations, and
b) the iana.org site seems not to host a tool for online look-up of

If instead the first two letters of abbreviations are taken from the
ISO 3166-1 alpha-2 code, then double assignments are less likely since
they are recorded closer to each other in the source code.

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin


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