A Timezone Gazetteer (and Map Maybe)

Dave Skinner dave at kirdu.jpl.nasa.gov
Wed Mar 19 22:58:28 UTC 1997

Any help in obtaining either or both of the following

	Internal Political Boundary Maps as Digital Line Graphs
	  (DLGs) instead of Bitmaps


	Surveyor Type Legal Descriptions of the Internal Timezone

for the countries that are currently composed of multiple different
timezones would be appreciated.  Note that in the United States, this
resolution has to go down to the county level, not just the state level,
and possibly only a surveyor type legal description will do in cases like


where the current description in the timezone database is "part of Crawford
County".  I believe that I can easily get the county maps for all 50 states
in this form, but I still need a surveyor type legal description of
situations like this, and complete lists of counties by timezone in states
that have more than one timezone.

At the international level, I already located a copy of the 132 MB CIA
Digital Line Graph database of the world that was released around 1990 under
the Freedom of Information Act.  It is composed only of line strokes, and
my ultimate goal is polygons.  So, the complete set of polygons that describe
the current international boundary of each country and any internal regional
timezones therein still have to be generated.  Nevertheless, it does have
international political boundaries as well as the boundaries of the states
of the United States and the provinces of Canada.  Other internal political
boundaries within the various countries are missing, however, and the
database also suffers from being out-of-date.  It is circa 1989.  Back on
the good news front, in case it should prove useful, the database does have
all significant rivers and other bodies of water down to a fairly fine level
of detail.

So, unless I find a better source of data, I need to bring this database
up-to-date.  To that end, I also need the current international political
boundaries, probably in surveyor type legal descriptions, that correct
all that has happened, especially in Europe and Asia, since the reunification
of Germany and the breakup of the Soviet Union.

At the internal political boundary level, I analyzed the timezone database
and extracted a complete list of all countries (21 in all) that have
multiple different current timezones, where "different" is defined as either
a different current GMT offset and/or a different current daylight savings
time rule.  This list is summarized in the table that appears below.

Within this table are 6 timezones

	9.*     australasia/New_Zealand
	11.*    europe:Norway
	12.*    europe:Portugal
	14.*    europe:Spain
	20.*    southamerica:Chile
	21.*    southamerica:Ecuador

that were edited to have an asterisk ("*") appended to their number to
indicate that it seems obvious where to draw a boundary between their
constituent timezones.  It seems obvious because the two distinct timezones
involved in each case are distinguished from each other by one being on the
mainland and the other being on an offshore island.

This leaves the following 15 countries

	1.      africa:Zaire
	2.      asia:Indonesia
	3.      asia:Japan
	4.      asia:Kazakhstan
	5.      australasia:Australia
	6.      australasia:French_Polynesia
	7.      australasia:Kiribati
	8.      australasia:Micronesia
	10.     europe:Denmark
	13.     europe:Russia
	15.     europe:Ukraine
	16.     northamerica:Canada
	17.     northamerica:Mexico
	18.     northamerica:United_States
	19.     southamerica:Brazil

where the exact boundary lines between their internal regional timezones
must still be identified.

	File:Country				   GMT	 DST
	Timezones				Offset	Rule

1.	africa:Zaire
	Africa/Kinshasa				  1:00	None
	Africa/Lubumbashi			  2:00	None

2.	asia:Indonesia
	Asia/Jakarta				  7:00	None
	Asia/Ujung_Pandang			  8:00	None
	Asia/Jayapura				  9:00	None

3.	asia:Japan
	Asia/Ishigaki				  8:00	None
	Asia/Tokyo				  9:00	None

4.	asia:Kazakhstan
	Asia/Aqtau				  4:00	E-Eur
	Asia/Aqtobe				  5:00	E-Eur
	Asia/Alma-Ata				  6:00	E-Eur

5.	australasia:Australia
	Indian/Christmas			  7:00	None
	Australia, Western			  8:00
		Australia/Perth		 	  8:00	None
	Australia, Central			  9:30
		Australia/Adelaide		  9:30	AS
		Australia/Darwin		  9:30	Aus
	Australia, Eastern			 10:00
		Australia/Brisbane		 10:00	AQ
		Australia/Sydney		 10:00	AN
	Australia/Lord_Howe			 10:30	LH

6.	australasia:French_Polynesia
	Pacific/Tahiti				-10:00	None
	Pacific/Marquesas			 -9:30	None
	Pacific/Gambier				 -9:00	None

7.	australasia:Kiribati
	Pacific/Tarawa				 12:00	None
	Pacific/Enderbury			 13:00	None
	Pacific/Kiritimati			 14:00	None

8.	australasia:Micronesia
	Pacific/Yap				 10:00	None
	Pacific/Ponape (Pohnpei)		 11:00	None
	Pacific/Kosrae				 12:00	None

9.*	australasia/New_Zealand
	Pacific/Auckland			 12:00	NZ
	Pacific/Chatham				 12:45	Chatham

10.	europe:Denmark
	America/Thule				 -4:00	Thule
	America/Godthab (Nuuk)			 -3:00	EU
	America/Scoresbysund (Ittoqqortoormiit)	 -1:00	EU
	Atlantic/Faeroe (Faroe Islands)		  0:00	EU
	Europe/Copenhagen			  1:00	EU

11.*	europe:Norway
	Atlantic/Jan_Mayen			 -1:00	None
	Europe/Oslo				  1:00	EU

12.*	europe:Portugal
	Atlantic/Azores				 -1:00	EU
	Europe/Lisbon				  0:00	EU

13.	europe:Russia
	Europe/Kaliningrad			  2:00	Russia
	Europe/Moscow				  3:00	Russia
	Europe/Samara				  4:00	Russia
	Europe/Yekaterinburg			  5:00	Russia
	Asia/Novosibirsk			  6:00	Russia
	Asia/Krasnoyarsk			  7:00	Russia
	Asia/Irkutsk				  8:00	Russia
	Asia/Yakutsk				  9:00	Russia
	Asia/Vladivostok			 10:00	Russia
	Asia/Magadan				 11:00	Russia
	Asia/Kamchatka				 12:00	Russia
	Asia/Anadyr				 13:00	Russia

14.*	europe:Spain
	Atlantic/Canary				  0:00	EU
	Europe/Madrid				  1:00	EU

15.	europe:Ukraine
	Europe/Kiev				  2:00	EU
	Europe/Simferopol			  3:00	Crimea

16.	northamerica:Canada
	Canada, Pacific				 -8:00
		America/Vancouver	 	 -8:00	Vanc
	Canada, Mountain			 -7:00
		America/Dawson_Creek	 	 -7:00	None
		America/Edmonton	 	 -7:00	Edm
	Canada, Central				 -6:00
		America/Regina		 	 -6:00	None
		America/Winnipeg	 	 -6:00	Winn
	Canada, Eastern				 -5:00
		America/Montreal	 	 -5:00	Mont
	Canada, Atlantic			 -4:00
		America/Halifax		 	 -4:00	Halifax
	Canada, Newfoundland			 -3:30
		America/St_Johns	 	 -3:30	StJohns

17.	northamerica:Mexico
	Mexico, Pacific				 -8:00
		America/Tijuana		 	 -8:00	Mexico
	Mexico, Mountain			 -7:00
		America/Mazatlan	 	 -7:00	Mexico
	Mexico, Central				 -6:00
		America/Mexico_City	 	 -6:00	Mexico

18.	northamerica:United_States
	United_States, Samoa			-11:00
		Pacific/Midway			-11:00	None
	United_States, Hawaii-Aleutian		-10:00
		America/Adak			-10:00	US
		Pacific/Honolulu		-10:00	None
	United_States, Alaska			 -9:00
		America/Anchorage	 	 -9:00	US
	United_States, Pacific			 -8:00
		America/Los_Angeles	 	 -8:00	US
	United_States, Mountain			 -7:00
		America/Denver		 	 -7:00	US
		America/Phoenix		 	 -7:00	None
	United_States, Central			 -6:00
		America/Chicago		 	 -6:00	US
	United_States, Eastern			 -5:00
		America/Indianapolis		 -5:00	None
		America/New_York	 	 -5:00	US

19.	southamerica:Brazil
	America/Porto_Acre			 -5:00	None
	Brazil, Western				 -4:00
		America/Cuiaba			 -4:00	Brazil
		America/Manaus			 -4:00	None
	Brazil, Eastern				 -3:00
		America/Fortaleza		 -3:00	None
		America/Sao_Paulo		 -3:00	Brazil
	America/Noronha				 -2:00	None

20.*	southamerica:Chile
	Pacific/Easter				 -6:00	Chile
	America/Santiago			 -4:00	Chile

21.*	southamerica:Ecuador
	Pacific/Galapagos			 -6:00	None
	America/Guayaquil			 -5:00	None

The following list of timezone database entries that are currently
operational duplicates of table entries above is provided for completeness.
This list was generated by Paul Eggert.

	Africa/Ceuta (duplicate of Europe/Madrid)
	America/Boise (duplicate of America/Denver)
	America/Dawson, America/Whitehorse \
	  (duplicates of America/Vancouver)
	America/Detroit, America/Louisville \
	  (duplicates of America/New_York)
	America/Glace_Bay, America/Goose_Bay, America/Pangnirtung \
	  (duplicates of America/Halifax)
	America/Ensenada (duplicate of America/Tijuana)
	America/Indiana/Knox, America/Indiana/Marengo, \
	  America/Indiana/Vevay (duplicates of America/Indianapolis)
	America/Inuvik, America/Yellowknife \
	  (duplicates of America/Edmonton)
	America/Iqaluit, America/Nipigon, America/Thunder_Bay \
	  (duplicates of America/Montreal)
	America/Juneau, America/Nome, America/Yakutat \
	  (duplicates of America/Anchorage)
	America/Maceio (duplicate of America/Sao_Paulo)
	America/Menominee (duplicate of America/Chicago)
	America/Rainy_River, America/Rankin_Inlet \
	  (duplicates of America/Winnipeg)
	America/Swift_Current (duplicate of America/Regina)
	Asia/Omsk (duplicate of Asia/Novosibirsk)
	Atlantic/Madeira (duplicate of Europe/Lisbon)
	Australia/Broken_Hill (duplicate of Australia/Adelaide)
	Australia/Hobart, Australia/Melbourne \
	  (duplicates of Australia/Sydney)
	Australia/Lindeman (duplicate of Australia/Brisbane)
	Pacific/Truk (duplicate of Pacific/Yap)

Anyhow, thanks in advance for any help that you end up providing.

Dave Skinner
dave at kirdu.jpl.nasa.gov

P.S.  I also wanted to thank both Paul Eggert and Eric Ulevik for replying
to my original email (to tz at elsie.nci.nih.gov), and I especially wanted to
thank Paul Eggert for reviewing my original version of this email as well.

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