Wikipedia:Reference desk/Archives/Miscellaneous/2014 October 29

= October 29 =

Time zones at the shore
Looking at this map, I noticed several areas where a time zone boundary appears to coincide with a shoreline – the northern and western coasts of France, the coasts of Argentina and Uruguay, most of the West African coast, etc. In these places, does the time really change the moment I step from a pier onto a boat, or does the national time include, say, the 12 nautical miles of a country's territorial waters? --Lazar Taxon (talk) 06:34, 29 October 2014 (UTC)


 * See Nautical time and Time zone. The legal boundary appears to be the territorial limit, though in practice ships aren't obliged to change clocks as they cross - nautical time is really only important for radio communications and the like, where an agreed standard is essential. AndyTheGrump (talk) 06:50, 29 October 2014 (UTC)


 * Since each country is able to pass laws to define the time zone it wishes to use - and can presumably enforce those laws within it's territorial waters...it's hard to see how the legal boundary could be anything other than the territorial limit.  International law might say something different - but it's kinda irrelevant when a coastguard officer arrests you for entering their waters without appropriate lighting for that time of day because you're operating in a different time zone than that country chooses to impose. SteveBaker (talk) 14:26, 29 October 2014 (UTC)