TimeZones and international waters

Christina Lawrence CLawrence at stopwatchmaps.com
Sun Jul 1 18:38:00 UTC 2007

Thank you for the response!

What distance from shore defines "the territorial waters of any nation"?
Is it nation specific, or an internationally recognized distance from

Thank you!


-----Original Message-----
From: Paul Eggert [mailto:eggert at CS.UCLA.EDU] 
Sent: Thursday, June 21, 2007 12:56 PM
To: tz at elsie.nci.nih.gov
Cc: Christina Lawrence
Subject: Re: TimeZones and international waters

To help clear this up I'll add something like the following to my next
proposed patch.  Comments welcome.

A ship within the territorial waters of any nation uses that nation's
time. In international waters, time zone boundaries are meridians
15° apart, except that UTC−12 and UTC+12 are each 7.5°
wide and are separated by the 180° meridian (not by the
International Date Line, which is for land and territorial waters
only). A captain can change ship's clocks any time after entering a
new time zone; midnight changes are common.

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