[tz] Theory - proposal to delete the reference to population

Tobias Conradi tobias.conradi at gmail.com
Sat May 12 01:37:39 UTC 2012

References to population in tzcode2012b/Theory
1) "However, uninhabited ISO 3166 regions like Bouvet Island do not need
locations, since local time is not defined there."

2) "Use UTC (with time zone abbreviation "zzz") for locations while

http://wikitravel.org/en/Bouvet_Island reports Olav Peak exists on
Bouvet Island, without discussing a need for the peak.

It is out of the scope of the tzdb as defined in the Theory file to
decide on whether regions need locations.

1b) there is no definition of "uninhabited"
German WP reports a team of people has been there after the 1970-01-01
cutoff point:
"Vom 24. Dezember 1978 bis zum 8. März 1979 hielt sich ein
norwegisches Forschungsteam auf der Insel auf und führte biologische
und geologische Forschungsarbeiten durch."

There are more sources supporting the claim that it had been populated.

1c) There is no evidence that local time is not defined if a
population is absent.

is mostly uninhabited but the whole area is observing UTC-09:00 according to

maybe covered by
America/Anchorage	Alaska Time
but no further geographic description found

HM as no zone, but
"To ensure accuracy of information, timegenie.com contacted the
Australian Antarctic Division [http://www.antarctica.gov.au/] . On
January 3, 2005, a senior official confirmed that Heard Island and
McDonald Islands are UTC/GMT +5 hours."

2a) A location changes its UTC offset when people move out or in?
on UTC most of the year?

A ship landing on an island, changes the UTC offset observed on that island?

The time a meteorite lands on island depends on whether people have
been there or not?

1+2) Violate tzcode2012b/Theory:

----- Scope of the tz database -----

The tz database attempts to record the history and predicted future of
all computer-based clocks that track civil time.  To represent this
data, the world is partitioned into regions whose clocks all agree
about time stamps that occur after the somewhat-arbitrary cutoff point
of the POSIX Epoch (1970-01-01 00:00:00 UTC).

1+2) Are inconsistently applied. Uninhabited locations are treated
differently, depending on whether they are located in countries that
have been inhabited during all time between 1970-01-01 and 2012-05-12
or not.

If Bouvet Island would be part of TF, it could be included in a zone
but since it is covered by BV it is not.

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin


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