LMT information, geographics of Antarctica bases

Paul Eggert eggert at CS.UCLA.EDU
Mon Mar 21 23:26:59 UTC 2005

Oscar van Vlijmen <ovv at hetnet.nl> writes:

> Some LMT (local mean time) values in the tz database seem to be incorrect.
> Below are the values I believe to be correct.
> Alaska    America/Juneau    -8:57:41
> Alaska    America/Anchorage    -9:59:36
> Alaska    America/Nome    -11:01:38
> Alaska    America/Adak    -11:46:38
> Philippines    Asia/Manila    8:04:00
> Guam    Pacific/Guam    9:39:00
> Northern Mariana Islands    Pacific/Saipan    9:43:00
> Samoa    Pacific/Apia    -11:26:56
> American Samoa    Pacific/Pago_Pago    -11:22:48

These LMT offsets agree with the current tz database.  I would guess
that your procedure got confused by the fact that these locations
started out on the opposite side of the International Date Line,
compared to where they are now.

> Alaska    America/Yakutat    -9:14:55

Are you sure about that one?
<http://www.welcometoalaska.com/yakutat.htm> says Yakutat is 139.72722
degrees west, which corresponds to -9:18:55, which is what is in the
current tz database.

> Note that West Samoa is no longer the correct name; it is Samoa.

Thanks; I'll update australasia and iso3166.tab accordingly.

> No LMT information was given for:
> BIOT    Indian/Chagos    4:49:40
> Cocos Islands    Indian/Cocos    6:27:40

This was because we don't know when standard time was introduced in
these locations.  Might as well put something in rather than nothing,
so I'll guess 1907 and 1900, respectively.  1907 because Chagos was
part of Mauritius at the time, and we have Mauritius introducing
standard time in 1907.  1900 because all we know is that it must have
occurred while the Ross family was ruling Cocos (1830-1978) and we
might as well guess 1900 as any other time.

> Some time ago I looked the latitude/longitude up from various sources, some
> more reliable than others.
> Locations missing in the tz database are:

Thanks; I'll update the base info accordingly.  (One minor point: I
don't bother to keep coordinates in "antartica" if they're already in
zone.tab, or if they are for large regions like the South Orkneys.)

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