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Timezone boundaries
by Oscar van Vlijmen Jan. 5, 2000

Jan. 5, 2000

This was part of a mail from Oscar van Vlijmen: > [...] Theoretical timezones: > Take [0;15W), [15;30W),..., [165;180W), [180E;165E),..., [15E;0E) > Times in hours from UT. [ means including, ) means not including. > 0-15E +1 [...] Gwillim Law wrote: Minor correction: what I was trying to express was that ships at sea should use UTC between 7.5 degrees E and 7.5 degrees W, UTC+1 between 7.5 degrees E and 22.5 degrees E, etc. Oscar replies: Gwillim could be very right. Looking carefully at for instance the "standard time zones" map from HM Nautical Almanac Office and the map "standard time zones of the world" from the CIA world factbook (both of which maps btw are not up to date), then I can see that they reflect the situation Gwillim depicts. Another flaw in my list was the absence of a UT+0 zone. Thanks for all your remarks. Here is the new list: Theoretical timezones: Times in hours from UT. [ ] means including, ( ) means not including. This rather arbitrary distinction is needed for mathematical reasons, i.e. when implementing in a program. longitude range time offset [7.5W-7.5E) +0 [7.5E-22.5E) +1 [22.5E-37.5E) +2 [37.5E-52.5E) +3 [52.5E-67.5E) +4 [67.5E-82.5E) +5 [82.5E-97.5E) +6 [97.5E-112.5E) +7 [112.5E-127.5E) +8 [127.5E-142.5E) +9 [142.5E-157.5E) +10 [157.5E-172.5E) +11 [172.5E-180E) +12 (172.5W-180W] -12 (157.5W-172.5W] -11 (142.5W-157.5W] -10 (127.5W-142.5W] -9 (112.5W-127.5W] -8 (97.5W-112.5W] -7 (82.5W-97.5W] -6 (67.5W-82.5W] -5 (52.5W-67.5W] -4 (37.5W-52.5W] -3 (22.5W-37.5W] -2 (7.5W-22.5W] -1 Oscar van Vlijmen 2000-01-05

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International Date Line, international waters
by Oscar van Vlijmen Jan. 5, 2000

Jan. 5, 2000

Gwillim Law wrote: >The International Date Line is not defined by any international standard, >convention, or treaty. Mapmakers are free to draw it as they please. >Reputable mapmakers will simply ensure that every point of land appears on >the correct side of the IDL, according to the date legally observed there. >When Kiribati adopted a uniform date in 1995, thereby moving the Phoenix and >Line Islands to the west side of the IDL (or, if you prefer, moving the IDL >to the east side of the Phoenix and Line Islands), I suppose that most >mapmakers redrew the IDL following the boundary of Kiribati. Even that line >has a rather arbitrary nature. The straight-line boundaries between Pacific >island nations that are shown on many maps are based on an international >convention, but are not legally binding national borders. It is possible that this is the most accurate answer given thusfar. About those straight line borders between the Pacific island nations: My copy of the "Reference map of oceania" from the University of Hawaii Press shows only CURVED boundaries. The latest edition of the Times Atlas, the 10th comprehensive edition, shows super straight boundary lines. On the University of Hawaii press map you can find a large spot of "no man's water" enclosed by the boundaries of Micronesia, Nauru, Gilbert Islands, Tuvalu, Solomon Islands and Papua New Guinea. The Times atlas gives the impression that this "no man's water" is just part of the Solomon Islands, Papua New Guinea and the rest respectively. Furthermore, the Times atlas gives the impression that Niue, the example Gwillim Law gave, is part of the Cook Islands including (!) Tokelau and that a straight border runs immediately left of Niue's island with main city Alofi. The University of Hawaii press map by contrast, shows a curved border about 200 kilometers left of Niue, and also separate curved borders around the Cook Islands and the Tokelau Islands. Tokelau is annotated being a dependency of New Zealand, the Cook Islands are "free associated" with New Zealand and Niue has no status. The US Office of the Geographer and Global Issues of the State Department lists Niue as a New Zealand dependency, just like Tokelau and Cook (http://www.state.gov/www/regions/dependencies.html) There is probably more on the subject boundaries in: Law of the Sea, student edition: Chapter 5. Baselines, zones, limits and boundaries. I can't find a complete on-line edition and I do no possess a printed copy. It appears that in 1994 60 nations ratified the UN-sponsored Law of the Sea Treaty of 1982, which establishes a 12-mile limit for territorial waters, but many provisions already have been internationally accepted. These are 12 nautical miles, so 1852 x 12 = 22224 meters. The Treaty stipulates a 200 nautical mile exclusive economic zone, for instance for regulating fishing rights and rights for mineral exploitation. The forerunner of the Law of the sea Treaty 1982, with respect to territorial boundaries, is the Convention on the Territorial Sea and the Contiguous Zone of 1958. This one is on-line: http://sedac.ciesin.org/pidb/texts/territorial.contiguous.zone.1958.html Are we still talking timezones? Yes, Gwillim Law noted: >An Anglo-French Conference on Time-Keeping at Sea (June, 1917) agreed that >legal time on the high seas would be zone time, i.e., the standard time at >the nearest meridian that is a multiple of fifteen degrees. When you are out of territorial waters (12 nm) you are in international waters and you should obey the theoretical timezone, innit? I made up the following list: Theoretical timezones: Take [0;15W), [15;30W),..., [165;180W), [180E;165E),..., [15E;0E) Times in hours from UT. [ means including, ) means not including. 0-15E +1 15-30E +2 30-45E +3 45-60E +4 60-75E +5 75-90E +6 90-105E +7 105-120E +8 120-135E +9 135-150E +10 150-165E +11 165-180E +12 0-15W -1 15-30W -2 30-45W -3 45-60W -4 60-75W -5 75-90W -6 90-105W -7 105-120W -8 120-135W -9 135-150W -10 150-165W -11 165-180W -12 Is all this information useful or too silly to talk about? Oscar van Vlijmen 2000-01-05

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RE: International Date Line, international waters
by Law, Gwil Jr. Jan. 5, 2000

Jan. 5, 2000

Oscar van Vlijmen wrote: > [...] Gwillim Law noted: >>An Anglo-French Conference on Time-Keeping at Sea (June, 1917) agreed that >>legal time on the high seas would be zone time, i.e., the standard time at >>the nearest meridian that is a multiple of fifteen degrees. > [...] Theoretical timezones: > Take [0;15W), [15;30W),..., [165;180W), [180E;165E),..., [15E;0E) > Times in hours from UT. [ means including, ) means not including. > 0-15E +1 [...] Minor correction: what I was trying to express was that ships at sea should use UTC between 7.5 degrees E and 7.5 degrees W, UTC+1 between 7.5 degrees E and 22.5 degrees E, etc. Gwillim Law

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For your amusement
by Manavendra Thakur Jan. 4, 2000

Jan. 4, 2000

Hi folks, I've been an observer ("lurker") of this mailing list for some years now. In my previous life, I used to use the information to provide free timezone patches for European customers of the operating system my previous company produced. My grateful and humble thanks to all of you who have contributed to the upkeep of this precious resource over the years! As a small token, here's something for your amusement that I saw in the New York Times newswire... I find it amazing that Cameron's Corner in Australia straddles three timezones. (But probably this isn't news to anyone on this mailing list!) Manavendra Thakur mthakur(a)alum.mit.edu December 29, 1999 'Auld Lang Syne' by 3 By THE ASSOCIATED PRESS SYDNEY, Australia, Dec. 28 -- Party, party, party! New Year's Eve celebrations at Cameron's Corner, a remote settlement in Australia's Outback, will be in triplicate, the local bar owner said today. The tiny village about 740 miles northwest of Sydney straddles three state boundaries, and three times zones. This means it will witness the end of the old and the start of the new millennium not once, not twice, but three times in the space of just one hour and one minute. Cameron's Corner's usual population -- four -- is expected to swell to around 1,000 on Dec. 31 as revelers head there for a millennium party with a difference. Copyright 1999 The New York Times Company

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RE: International date line
by Law, Gwil Jr. Jan. 3, 2000

Jan. 3, 2000

John Cowan wrote: >> Niue, to take a simple example, is shown in my Rand McNally International >> Atlas surrounded by a rectangle extending from approximately 166.5 to 170.5 >> degrees West, and 17.5 to 23.5 degrees South. > > Okay. And this bounding box is defined by an international convention? > Or is it just RMcN's convention? I think it's an international convention. That's based on something I read several years ago. I don't have any reference for it at this date. As I tried to state, my original posting on this topic was more than mere speculation, but less than authoritative. Gwillim Law

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RE: International date line
by Law, Gwil Jr. Jan. 3, 2000

Jan. 3, 2000

John Cowan wrote: >> The straight-line boundaries between Pacific >> island nations that are shown on many maps are based on an international >> convention, but are not legally binding national borders. > > I'm confused. Does this mean that there are overlapping claims to sovereignty, > or what? What is a "legally binding national border" anyway? As I understand the situation, sovereignty extends to the land area of each island, plus its territorial waters (the twelve-mile limit, or whatever the individual country claims). The "straight-line boundaries" I was talking about divide a large part of the Pacific into contiguous zones, extending well beyond the limits of sovereignty. Niue, to take a simple example, is shown in my Rand McNally International Atlas surrounded by a rectangle extending from approximately 166.5 to 170.5 degrees West, and 17.5 to 23.5 degrees South. The actual extent of Niue, including its territorial waters, can be contained within a rectangle from about 169.5 to 170.2 degrees West, and 18.7 to 19.4 degrees South. It would take me some time and effort to define "legally binding national border". I would define a "not-legally-binding-national-border" as a line on a map with no particular significance. Does that help? Gwillim Law

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RE: International date line
by Law, Gwil Jr. Jan. 3, 2000

Jan. 3, 2000

> Does anybody know the exact geographical coordinates of the international > date line? The International Date Line is not defined by any international standard, convention, or treaty. Mapmakers are free to draw it as they please. Reputable mapmakers will simply ensure that every point of land appears on the correct side of the IDL, according to the date legally observed there. When Kiribati adopted a uniform date in 1995, thereby moving the Phoenix and Line Islands to the west side of the IDL (or, if you prefer, moving the IDL to the east side of the Phoenix and Line Islands), I suppose that most mapmakers redrew the IDL following the boundary of Kiribati. Even that line has a rather arbitrary nature. The straight-line boundaries between Pacific island nations that are shown on many maps are based on an international convention, but are not legally binding national borders. An Anglo-French Conference on Time-Keeping at Sea (June, 1917) agreed that legal time on the high seas would be zone time, i.e., the standard time at the nearest meridian that is a multiple of fifteen degrees. The date is governed by the IDL; therefore, even on the high seas, there may be some places as late as fourteen hours later than UTC. And, since the IDL is not an international standard, there are some places on the high seas where the correct date is ambiguous. This information is the best I could find when I was studying the question a few years ago. If any of the readers of this list have anything more authoritative, I would welcome corrections. Gwillim Law

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International date line
by Oscar van Vlijmen Jan. 3, 2000

Jan. 3, 2000

Wishing every reader the very best for this millennium, I would like to ask: Does anybody know the exact geographical coordinates of the international date line? I have compiled from some of the better maps a very speculative list of coordinates and I hope that somebody is able to correct this list. 90N 180W (North pole) 75N 180W 68N 168W 66N 168W 53N 170E 47N 180W and now the Kiribati swing 2.5N 180W 0N 177W 0N 166.5W 3.3S 166.5W 3.3S 160W 2N 160W and now diagonally to, or first via 2N 162W? 5N 162W 5N 154.5W 2.3N 152.25W 7S 149W 12S 149W 12S 157W 7S 157W 7S 178.5W and following again the original line: 15.5S 172.25W 45S 172.25W 51S 180W 90S 180W (South pole) Regards, Oscar van Vlijmen 2000-01-01

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Re: Could anyone help, corrected URL
by Oscar van Vlijmen Dec. 29, 1999

Dec. 29, 1999

To: "Dave's DHL Mail" <dkelly(a)lhr-sys.dhl.com> And copy to: tz(a)elsie.nci.nih.gov Dave wrote: >I'd like to produce a list of all the distict beginnings of the new >millenium - listing the zone and UTC time when they will first see the new >millenium, e.g.: > >Pacific/Chatham Island Dec 31 10:15 UTC >.... >Europe/Paris Dec 31 23:00 UTC >Europe/London Jan 1 00:00 UTC >... >etc.. > >Dave Kelly Hi! I have recently made a Macintosh HyperCard application, based upon the TZ database information. Can be found on my site. Furthermore, I have made a small list with the first zones and the last zones that will greet the new millennium. This list can be found at: http://www.tip.nl/users/o.van.vlijmen/firstlatestzones.html Without any notice my service provider changed something in the naming of URL's, resulting in an error if you try to follow the given URL. My page still exists, use the 'direct' address: http://www1.tip.nl/~t876506/firstlatestzones.html Regards, Oscar van Vlijmen 29-12-1999

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Could anyone help
by Dave's DHL Mail Dec. 29, 1999

Dec. 29, 1999

Hello Everyone, First, thanks to all on the list for the useful (and often amusing) information that's been passed round for the last couple of years. Next, I wonder if anyone can help with a little light hearted excercise - I'm afraid my coding isn't up to it and I don't have access to a compiler at home anyway... I'd like to produce a list of all the distict beginnings of the new millenium - listing the zone and UTC time when they will first see the new millenium, e.g.: Pacific/Chatham Island Dec 31 10:15 UTC .... Europe/Paris Dec 31 23:00 UTC Europe/London Jan 1 00:00 UTC ... etc.. I'd be really grateful if anyone can help with this, or alternatively point me to a list that already exists on the web somewhere. Thanks again, and best wishes for *your* new Millennium Dave Kelly

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