proposed tz changes for Argentina, Cuba, Hong Kong, Mongolia, Sonora

Paul Eggert eggert at twinsun.com
Tue Jan 11 08:15:42 UTC 2000


Here are some proposed changes to the tz database reflecting recent
discussions on this list, plus some research and private email.
Thanks to everybody who contributed.

* Changes to data.
  - Argentina switched from UTC-3 without DST to UTC-4 with DST last spring.
    Wall clocks are affected starting March 5.
  (Thanks to Rives McDow for this info.)

  - Sonora stopped observing DST last year; new zone America/Hermosillo.
  (Thanks to Gwillim Law and Rives McDow for this info.)

  - Mongolia stopped observing DST last year.
  - New Zone Asia/Hovd for east Mongolia.
  - Asia/Ulaanbaatar renamed from Asia/Ulan_Bator, to reflect most popular
    spelling these days.  Backward entry created.
  (Thanks to Gwillim Law, Rives McDow, and Oscar van Vlijmen for this info.)

  - Post-1999 Cuban DST starts the first Sunday in April, not April 1.
  (Thanks to Gwillim Law for this info.)

  - Add backward entry for GB-Eire, a Zone that was removed in 1993.
  (Sorry, I've forgotten who reported this problem.)

  - Change Hong Kong time abbreviation back to `HKT', as it's the most popular.

* Changes to commentary
  - Update web links.  Add pointers to HyperCard port, to Astrodienst for
    Shanks data, to NRAO for astronomical time, to JPL for spaceflight time,
    and to webexhibits for DST history (replacing energy.ca.gov).
  - Fix HTML typos in Arts.htm, found by nsgmls.
  - Add discussion of the International Date Line (thanks to Gwillim Law).
  - Update Antarctic base info.
  - More comments about the Nunavut time zone controversy.

===================================================================
RCS file: RCS/antarctica,v
retrieving revision 1999.5
retrieving revision 1999.5.0.1
diff -pu -r1999.5 -r1999.5.0.1
--- antarctica	1999/08/17 18:42:13	1999.5
+++ antarctica	2000/01/11 07:46:46	1999.5.0.1
@@ -1,9 +1,9 @@
 # @(#)antarctica	7.16
 
-# From Paul Eggert (1999-03-22):
+# From Paul Eggert (1999-11-15):
 # To keep things manageable, we list only locations occupied year-round; see
-# <a href="http://www.delm.tas.gov.au/comnap/members.html">
-# Antarctic Activities of Member Nations of the Antarctic Treaty (1996-05-24)
+# <a href="http://www.comnap.aq/comnap/comnap.nsf/P/Stations/">
+# COMNAP - Stations and Bases
 # </a>
 # and
 # <a href="http://www.spri.cam.ac.uk/bob/periant.htm">
@@ -35,18 +35,24 @@ Rule	ChileAQ	1999	max	-	Oct	Sun>=9	0:00	
 Rule	ChileAQ	2000	max	-	Mar	Sun>=9	0:00	0	-
 
 
-# Argentina - 6 year-round bases
-# General Belgrano II
-# 5 others
+# Argentina - year-round bases
+# Belgrano II, Confin Coast, -770227-0343737, since 1972-02-05
+# Esperanza, San Martin Land, -6323-05659, since 1952-12-17
+# Jubany, Potter Peninsula, King George Island, -6414-0602320, since 1982-01
+# Marambio, Seymour I, -6414-05637, since 1969-10-29
+# Orcadas, Laurie I, -6016-04444, since 1904-02-22
+# San Martin, Debenham I, -6807-06708, since 1951-03-21
+#	(except 1960-03 / 1976-03-21)
 
 # Australia - territories
 # Heard Island, McDonald Islands (uninhabited)
 #	previously sealers and scientific personnel wintered
 #
 # year-round bases
-# Casey, Bailey Peninsula, since 1969
-# Davis, Vestfold Hills, since 1957-01-13 (except 1964-11 - 1969-02)
-# Mawson, Holme Bay, since 1954-02-13
+# Casey, Bailey Peninsula, -6617+11032, since 1969
+# Davis, Vestfold Hills, -6835+07759, since 1957-01-13
+#	(except 1964-11 - 1969-02)
+# Mawson, Holme Bay, -6736+06253, since 1954-02-13
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone Antarctica/Casey	0	-	___	1969
 			8:00	-	WST	# Western (Aus) Standard Time
@@ -70,15 +76,16 @@ Zone Antarctica/Mawson	0	-	___	1954 Feb 
 # Brazil - year-round base
 # Ferraz, King George Island, since 1983/4
 
-# Chile - 4 year-round bases
+# Chile - year-round bases
+# Escudero, South Shetland Is, -621157-0585735, since 1994
+# Frei, King George Is, -6214-05848, since 1969
+# O'Higgins, Antarctic Peninsula, -6319-05704, since 1948-02
+# Prat, -6230-05941
 
 # China - year-round bases
 # Great Wall, King George Island, since 1985-02-20
 # Zhongshan, Larsemann Hills, Prydz Bay, since 1989-02-26
 
-# Finland - year-round base
-# Aboa, Queen Maud Land, since 1988
-
 # France - year-round bases
 #
 # From Antoine Leca <Antoine.Leca at Renault.FR> (1997-01-20):
@@ -103,7 +110,7 @@ Zone Indian/Kerguelen	0	-	___	1950	# Por
 			5:00	-	TFT	# ISO code TF Time
 #
 # year-round base in the main continent
-# Dumont-d'Urville, Terre Adelie (Adelie Land), -6640+14001, since 1956-11
+# Dumont-d'Urville, Ile des Petrels, -6640+14001, since 1956-11
 #
 # Another base at Port-Martin, 50km east, began operation in 1947.
 # It was destroyed by fire on 1952-01-14.
@@ -172,11 +179,11 @@ Rule	NZAQ	1990	max	-	Mar	Sun>=15	2:00s	0
 # Peter I Island (never inhabited)
 
 # Poland - year-round base
-# Arctowski, King George Island, since 1977
+# Arctowski, King George Island, -620945-0582745, since 1977
 
 # Russia - year-round bases
-# Bellingshausen, King George Island
-# Mirny
+# Bellingshausen, King George Island, -621159-0585337, since 1968-02-22
+# Mirny, Davis coast, -6633+09301, since 1956-02
 # Molodezhnaya
 # Novolazarevskaya
 # Vostok
@@ -198,11 +205,12 @@ Rule	NZAQ	1990	max	-	Mar	Sun>=15	2:00s	0
 #	and a garrison was deployed briefly
 #
 # year-round bases
+# Bird Island, South Georgia, -5400-03803, since 1983
 # Halley, Coates Land, -7535-2619, since 1956-01-06
 # Rothera, Adelaide Island, -6734-6808, since 1976-12-01
 
 # Uruguay - year round base
-# Artigas, King George Island
+# Artigas, King George Island, -9621104-0585107
 
 # USA - year-round bases
 #
===================================================================
RCS file: RCS/Arts.htm,v
retrieving revision 7.27
retrieving revision 7.27.0.1
diff -pu -r7.27 -r7.27.0.1
--- Arts.htm	1999/11/15 23:43:22	7.27
+++ Arts.htm	2000/01/11 07:46:46	7.27.0.1
@@ -5,11 +5,9 @@
 </HEAD>
 <BODY>
 <H1>Time and the Arts</H1>
-<P>
 <H6>
 @(#)Arts.htm	7.27
 </H6>
-</P>
 <PRE>
 "Is that a pertinent fact, or are you trying to dazzle me with your command
 of time zones?"
@@ -30,7 +28,7 @@ Personnel:	Karrin Allyson, vocal
 Notes:		CD notes "additional lyric by Karrin Allyson;
 		arranged by Russ Long and Karrin Allyson"
 ADO Rating:	1 star
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A175928">AMG Rating:	4 stars</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A175928">AMG Rating:	4 stars</A>
 Penguin Rating:	3.5 stars
 --------------------------------------------------------------------------
 Artist:		Kevin Mahogany
@@ -45,7 +43,7 @@ Personnel:	Kevin Mahogany, vocal
 		Ralph Moore, tenor saxophone
 		Lewis Nash, drums
 ADO Rating:	1.5 stars
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A262654">AMG Rating:	3 stars</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A262654">AMG Rating:	3 stars</A>
 Penguin Rating:	3 stars
 --------------------------------------------------------------------------
 Artist:		Joe Williams
@@ -59,7 +57,7 @@ Personnel:	Joe Williams, vocal
 Notes:		This CD is also available as part of a 3-CD package from
 		Telarc, "Triple Play" (CD-83461)
 ADO Rating:	black dot
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A194434">AMG Rating:	2 stars</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A194434">AMG Rating:	2 stars</A>
 Penguin Rating:	3 stars
 --------------------------------------------------------------------------
 Artist:		Charles Fambrough
@@ -76,7 +74,7 @@ Personnel:	Charles Fambrough, bass
 Notes:		On-line information and samples available at
 		<A HREF="http://wwmusic.com/~music/audioq/rel/1033.html">http://wwmusic.com/~music/audioq/rel/1033.html</A>
 ADO Rating:	2 stars
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A224430">AMG Rating:	unrated</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A224430">AMG Rating:	unrated</A>
 Penguin Rating:	3 stars
 ==========================================================================
 Also of note:
@@ -93,7 +91,7 @@ Personnel:	Holly Cole, voice
 Notes:		Lyrical reference to "Eastern Standard Time" in
 			Tom Waits' "Purple Avenue"
 ADO Rating:	2.5 stars
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A157959">AMG Rating:	3 stars</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A157959">AMG Rating:	3 stars</A>
 Penguin Rating:	unrated
 --------------------------------------------------------------------------
 Artist:		Milt Hinton
@@ -124,7 +122,7 @@ Notes:		tunes include Old Man Time, Time
 		On-line samples available at
 		<A HREF="http://www.globalmusic.com/labels/chiaroscuro/chiaro_cd_gallery.html">http://www.globalmusic.com/labels/chiaroscuro/chiaro_cd_gallery.html</A>
 ADO Rating:	3 stars
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A162344">AMG Rating:	4.5 stars</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A162344">AMG Rating:	4.5 stars</A>
 Penguin Rating:	3 stars
 --------------------------------------------------------------------------
 Artist:		Paul Broadbent
@@ -138,7 +136,7 @@ Personnel:	Paul Broadbent, piano
 		Frank Gibson, Jr., drums
 Notes:		The CD cover features an analemma for equation-of-time fans
 ADO Rating:	1 star
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A223722">AMG Rating:	4 stars</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A223722">AMG Rating:	4 stars</A>
 Penguin Rating:	3.5 stars
 --------------------------------------------------------------------------
 Artist:		Anthony Braxton/Richard Teitelbaum
@@ -153,7 +151,7 @@ Personnel:	Anthony Braxton, sporanino an
 		Leroy Jenkins, violin and miscellaneous instruments
 		Richard Teitelbaum, modular moog and micromoog synthesizer
 ADO Rating:	black dot
-<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&sql=A310757">AMG Rating:	unrated</A>
+<A HREF="http://www.allmusic.com/cg/x.dll?p=amg&amp;sql=A310757">AMG Rating:	unrated</A>
 --------------------------------------------------------------------------
 Artist:		Jules Verne
 Book:		Le Tour du Monde en Quatre-Vingts Jours
===================================================================
RCS file: RCS/asia,v
retrieving revision 1999.10
retrieving revision 1999.10.0.1
diff -pu -r1999.10 -r1999.10.0.1
--- asia	1999/11/13 19:27:44	1999.10
+++ asia	2000/01/11 07:46:46	1999.10.0.1
@@ -84,8 +84,7 @@ Zone	Asia/Kabul	4:36:48 -	LMT	1890
 # <edd at AIC.NET> reported (1996-05-04) that Yerevan probably wouldn't use DST
 # in 1996, though it did use DST in 1995.  IATA SSIM (1991/1998) reports that
 # Armenia switched from 3:00 to 4:00 in 1998 and observed DST after 1991,
-# but started switching at 3:00s in 1998.  IATA SSIM (1999-02) reports
-# that they switch one day later in 2001 (i.e. on Mondays).
+# but started switching at 3:00s in 1998.
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Yerevan	2:58:00 -	LMT	1924 May  2
 			3:00	-	YERT	1957 Mar    # Yerevan Time
@@ -235,8 +234,7 @@ Rule	HK	1979	1980	-	May	Sun>=8	3:30	1:00
 Rule	HK	1979	1980	-	Oct	Sun>=16	3:30	0	-
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Hong_Kong	7:36:36 -	LMT	1904 Oct 30
-			8:00	HK	HK%sT	1997 Jul  1 # return to China
-			8:00	PRC	C%sT
+			8:00	HK	HK%sT
 
 
 ###############################################################################
@@ -853,31 +851,62 @@ Zone	Indian/Maldives	4:54:00 -	LMT	1880	
 			5:00	-	MVT		# Maldives Time
 
 # Mongolia
+
 # Shanks says that Mongolia has three time zones, but usno1995 and the CIA map
 # Standard Time Zones of the World (1997-01)
 # both say that it has just one.
-# Let's comment out the western and eastern Mongolian time zones
-# till we know what their principal towns are.
+
+# From Oscar van Vlijmen (1999-12-11):
+# <a href="http://www.mongoliatourism.gov.mn/general.htm">
+# General Information Mongolia
+# </a> (1999-09)
+# "Time: Mongolia has two time zones. Three westernmost provinces of
+# Bayan-Ulgii, Uvs, and Hovd are one hour earlier than the capital city, and
+# the rest of the country follows the Ulaanbaatar time, which is UTC/GMT plus
+# eight hours."
+
+# From Rives McDow (1999-12-13):
+# Mongolia discontinued the use of daylight savings time in 1999; 1998
+# being the last year it was implemented.  The dates of implementation I am
+# unsure of, but most probably it was similar to Russia, except for the time
+# of implementation may have been different....
+# Some maps in the past have indicated that there was an additional time
+# zone in the eastern part of Mongolia, including the provinces of Dornod,
+# Suhbaatar, and possibly Khentij.
+
+# From Paul Eggert (1999-12-15):
+# For now, we'll comment out the east zone (Choybalsan)
+# and use Shanks's and the IATA's data for the daylight-saving rules.
+# Naming and spelling is tricky in Mongolia.
+# We'll use Hovd (also spelled Chovd and Khovd) to represent the west zone;
+# the capital of the Hovd province is sometimes called Hovd, sometimes Dund-Us,
+# and sometimes Jirgalanta (with variant spellings), but the name Hovd
+# is good enough for our purposes.
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Mongol	1981	1984	-	Apr	1	0:00	1:00	S
 Rule	Mongol	1981	1984	-	Oct	1	0:00	0	-
 Rule	Mongol	1985	1990	-	Mar	lastSun	2:00	1:00	S
 Rule	Mongol	1985	1990	-	Sep	lastSun	3:00	0	-
-Rule	Mongol	1991	max	-	Mar	lastSun	0:00	1:00	S
+Rule	Mongol	1991	1998	-	Mar	lastSun	0:00	1:00	S
 Rule	Mongol	1991	1995	-	Sep	lastSun	0:00	0	-
 # IATA SSIM (1996-09) says 1996-10-25; go with Shanks.
 Rule	Mongol	1996	only	-	Oct	lastSun	0:00	0	-
-Rule	Mongol	1997	max	-	Sep	lastSun	0:00	0	-
+Rule	Mongol	1997	1998	-	Sep	lastSun	0:00	0	-
+# IATA SSIM (1999-09) says Mongolia no longer observes DST.
+
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
-#Zone	Asia/Dariv	6:14:32 -	LMT	1905 Aug
-#			6:00	-	DART	1978	# Dariv Time
-#			7:00	Mongol	DAR%sT
-Zone	Asia/Ulan_Bator	7:07:32 -	LMT	1905 Aug
-			7:00	-	ULAT	1978	# Ulan Bator Time
+Zone	Asia/Hovd	6:06:36 -	LMT	1905 Aug
+			6:00	-	HOVT	1978	# Hovd Time
+			7:00	Mongol	HOV%sT
+Zone	Asia/Ulaanbaatar 7:07:32 -	LMT	1905 Aug
+			7:00	-	ULAT	1978	# Ulaanbaatar Time
 			8:00	Mongol	ULA%sT
-#Zone Asia/Baruun-Urt	7:33:00 -	LMT	1905 Aug
-#			8:00	-	BART	1978	# Baruun-Urt Time
-#			9:00	Mongol	BAR%sT
+# We're not sure about this entry yet, so we'll omit it for now.
+#Zone Asia/Choybalsan	7:38:00 -	LMT	1905 Aug
+#			8:00	-	CHOT	1978	# Choybalsan Time
+#			9:00	Mongol	CHO%sT	19??
+#			8:00	Mongol	ULA%sT
 
 # Nepal
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
@@ -1097,7 +1126,8 @@ Rule	Syria	1993	only	-	Mar	26	0:00	1:00	
 Rule	Syria	1993	only	-	Sep	25	0:00	0	-
 # IATA SSIM (1998-02) says 1998-04-02;
 # (1998-09) says 1999-03-29 and 1999-09-29; (1999-02) says 1999-04-02,
-# 2000-04-02, and 2001-04-02; ignore all these claims and go with Shanks.
+# 2000-04-02, and 2001-04-02; (1999-09) says 2000-03-31 and 2001-03-31;
+# ignore all these claims and go with Shanks.
 Rule	Syria	1994	1996	-	Apr	 1	0:00	1:00	S
 Rule	Syria	1994	max	-	Oct	 1	0:00	0	-
 Rule	Syria	1997	1998	-	Mar	lastMon	0:00	1:00	S
===================================================================
RCS file: RCS/australasia,v
retrieving revision 1999.10
retrieving revision 1999.10.0.1
diff -pu -r1999.10 -r1999.10.0.1
--- australasia	1999/11/13 19:27:44	1999.10
+++ australasia	2000/01/11 07:46:46	1999.10.0.1
@@ -177,9 +177,6 @@ Zone Australia/Lord_Howe 10:36:20 -	LMT	
 # The Australian Bureau of Meteorology FAQ
 # </a> (1999-09-27) writes that Macquarie Island follows Tasmanian practice
 # irrespective of any local use of DST.  This is unclear; ignore it for now.
-#
-# Manihiki, Penrhyn, Rakehanga
-# no information
 
 # Christmas
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
@@ -348,7 +345,7 @@ Zone	Pacific/Norfolk	11:11:52 -	LMT	1901
 			11:12	-	NMT	1951	# Norfolk Mean Time
 			11:30	-	NFT		# Norfolk Time
 
-# Palau
+# Palau (Belau)
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Palau	8:57:56 -	LMT	1901		# Koror
 			9:00	-	PWT	# Palau Time
@@ -854,8 +851,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 
 ###############################################################################
 
-# New Zealand, from Elz' asia 1.1
-# Elz says "no guarantees"
+# New Zealand
 
 # From Mark Davies (1990-10-03):
 # the 1989/90 year was a trial of an extended "daylight saving" period.
@@ -896,6 +892,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 
 ###############################################################################
 
+
 # Fiji
 
 # Howse writes (p 153) that in 1879 the British governor of Fiji
@@ -907,6 +904,9 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # until 0300 local time 1999-02-28.  Each year the DST period will 
 # be from the first Sunday in November until the last Sunday in February.
 
+# From Paul Eggert (2000-01-08):
+# IATA SSIM (1999-09) says DST ends 0100 local time.  Go with McDow.
+
 # From the BBC World Service (1998-10-31 11:32 UTC):
 # The Fijiian government says the main reasons for the time change is to
 # improve productivity and reduce road accidents.  But correspondents say it
@@ -914,10 +914,12 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # islands in the effort to attract tourists to witness the dawning of the new
 # millenium.
 
+
 # Johnston
 
 # Johnston data is from usno1995.
 
+
 # Kiribati
 
 # From Paul Eggert (1996-01-22):
@@ -925,6 +927,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # ``declared it the same day throught the country as of Jan. 1, 1995''
 # as part of the competition to be first into the 21st century.
 
+
 # Kwajalein
 
 # In comp.risks 14.87 (26 August 1993), Peter Neumann writes:
@@ -933,6 +936,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # respect to the International Date Line, to rejoin its fellow islands,
 # going from 11:59 p.m. Thursday to 12:00 m. Saturday in a blink.
 
+
 # N Mariana Is, Guam
 
 # Howse writes (p 153) ``The Spaniards, on the other hand, reached the
@@ -940,6 +944,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # (now called the Marianas) kept American date for quite some time.
 # Ignore this for now, as we have no hard data.  See also Asia/Manila.
 
+
 # Micronesia
 
 # Alan Eugene Davis <adavis at kuentos.guam.net> writes (1996-03-16),
@@ -957,6 +962,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # that Truk and Yap are UTC+10, and Ponape and Kosrae are UTC+11.
 # We don't know when Kosrae switched from UTC+12; assume January 1 for now.
 
+
 # Pitcairn
 
 # From Rives McDow (1999-11-08):
@@ -980,6 +986,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # Pacific Standard Time. They used to be 1/2 hour different from us here in
 # Sacramento but it was changed a couple of years ago.
 
+
 # Samoa
 
 # Howse writes (p 153, citing p 10 of the 1883-11-18 New York Herald)
@@ -988,6 +995,7 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # ordaining -- by a masterpiece of diplomatic flattery -- that
 # the Fourth of July should be celebrated twice in that year.''
 
+
 # Tonga
 
 # From Paul Eggert (1996-01-22):
@@ -1057,3 +1065,31 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # From Rives McDow (1999-10-06):
 # Tonga started its Daylight Saving on Saturday morning October 2nd at 0200am.
 # Daylight Saving ends on April 16 at 0300am which is Sunday morning.
+
+
+###############################################################################
+
+# The International Date Line
+
+# From Gwillim Law (2000-01-03):
+# 
+# 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.
===================================================================
RCS file: RCS/backward,v
retrieving revision 1998.9
retrieving revision 1998.9.0.1
diff -pu -r1998.9 -r1998.9.0.1
--- backward	1999/11/08 22:27:22	1998.9
+++ backward	2000/01/11 07:46:46	1998.9.0.1
@@ -9,6 +9,7 @@ Link	America/Indianapolis	America/Fort_W
 Link	America/Indiana/Knox	America/Knox_IN
 Link	America/St_Thomas	America/Virgin
 Link	Asia/Jerusalem		Asia/Tel_Aviv
+Link	Asia/Ulaanbaatar	Asia/Ulan_Bator
 Link	Australia/Sydney	Australia/ACT
 Link	Australia/Sydney	Australia/Canberra
 Link	Australia/Lord_Howe	Australia/LHI
@@ -39,6 +40,7 @@ Link	America/Havana		Cuba
 Link	Africa/Cairo		Egypt
 Link	Europe/Dublin		Eire
 Link	Europe/London		GB
+Link	Europe/London		GB-Eire
 Link	Etc/GMT+0		GMT+0
 Link	Etc/GMT-0		GMT-0
 Link	Etc/GMT0		GMT0
===================================================================
RCS file: RCS/northamerica,v
retrieving revision 1999.10
retrieving revision 1999.10.0.1
diff -pu -r1999.10 -r1999.10.0.1
--- northamerica	1999/11/13 19:27:45	1999.10
+++ northamerica	2000/01/11 07:46:46	1999.10.0.1
@@ -952,6 +952,14 @@ Zone America/Dawson_Creek -8:00:56 -	LMT
 # their senses", but the locals evidently don't see any problem with
 # the current state of affairs.
 
+# From Michaela Rodrigue, writing in the
+# <a href="http://www.nunatsiaq.com/archives/nunavut991130/nvt91119_17.html">
+# Nunatsiaq News (1999-11-19)</a>:
+# Clyde River, Pangnirtung and Sanikiluaq now operate with two time zones,
+# central - or Nunavut time - for government offices, and eastern time
+# for municipal offices and schools....  Igloolik [was similar but then]
+# made the switch to central time on Saturday, Nov. 6.
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	NT_YK	1918	only	-	Apr	14	2:00	1:00	D
 Rule	NT_YK	1918	only	-	Oct	27	2:00	0	S
@@ -1079,6 +1087,12 @@ Zone America/Dawson	-9:17:40 -	LMT	1900 
 # The State of Quintana Roo has reverted back to central STD and DST times
 # (i.e. UTC -0600 and -0500 as of 1998-08-02).
 
+# From Rives McDow (2000-01-10):
+# Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time
+# zone 5 hours from the International Date Line, and will not observe daylight
+# savings time so as to stay on the same time zone as the southern part of
+# Arizona year round.
+
 # From Shanks:
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Mexico	1939	only	-	Feb	5	0:00	1:00	D
@@ -1120,7 +1134,19 @@ Zone America/Chihuahua	-7:04:20 -	LMT	19
 			-6:00	Mexico	C%sT	1998
 			-6:00	-	CST	1998 Apr Sun>=1 3:00
 			-7:00	Mexico	M%sT
-# S Baja California, Nayarit, Sinaloa, Sonora
+# Sonora
+Zone America/Hermosillo	-7:23:52 -	LMT	1921 Dec 31 23:36:08
+			-7:00	-	MST	1927 Jun 10 23:00
+			-6:00	-	CST	1930 Nov 15
+			-7:00	-	MST	1931 May  1 23:00
+			-6:00	-	CST	1931 Oct
+			-7:00	-	MST	1932 Mar 30 23:00
+			-6:00	-	CST	1942 Apr
+			-7:00	-	MST	1949 Jan 14
+			-8:00	-	PST	1970
+			-7:00	Mexico	M%sT	1999
+			-7:00	-	MST
+# S Baja California, Nayarit, Sinaloa
 Zone America/Mazatlan	-7:05:40 -	LMT	1921 Dec 31 23:54:20
 			-7:00	-	MST	1927 Jun 10 23:00
 			-6:00	-	CST	1930 Nov 15
@@ -1261,7 +1287,7 @@ Rule	Cuba	1996	only	-	Oct	 6	0:00s	0	S
 Rule	Cuba	1997	only	-	Oct	12	0:00s	0	S
 Rule	Cuba	1998	1999	-	Mar	lastSun	0:00s	1:00	D
 Rule	Cuba	1998	max	-	Oct	lastSun	0:00s	0	S
-Rule	Cuba	2000	max	-	Apr	 1	0:00s	1:00	D
+Rule	Cuba	2000	max	-	Apr	Sun>=1	0:00s	1:00	D
 
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	America/Havana	-5:29:28 -	LMT	1890
===================================================================
RCS file: RCS/southamerica,v
retrieving revision 1999.10
retrieving revision 1999.10.0.1
diff -pu -r1999.10 -r1999.10.0.1
--- southamerica	1999/11/13 19:27:45	1999.10
+++ southamerica	2000/01/11 07:46:46	1999.10.0.1
@@ -80,12 +80,12 @@ Rule	Arg	1963	only	-	Dec	15	0:00	1:00	S
 Rule	Arg	1964	1966	-	Mar	 1	0:00	0	-
 Rule	Arg	1964	1966	-	Oct	15	0:00	1:00	S
 Rule	Arg	1967	only	-	Apr	 1	0:00	0	-
-Rule	Arg	1967	1968	-	Oct	Sun<=7	0:00	1:00	S
-Rule	Arg	1968	1969	-	Apr	Sun<=7	0:00	0	-
+Rule	Arg	1967	1968	-	Oct	Sun>=1	0:00	1:00	S
+Rule	Arg	1968	1969	-	Apr	Sun>=1	0:00	0	-
 Rule	Arg	1974	only	-	Jan	23	0:00	1:00	S
 Rule	Arg	1974	only	-	May	 1	0:00	0	-
-Rule	Arg	1974	1976	-	Oct	Sun<=7	0:00	1:00	S
-Rule	Arg	1975	1977	-	Apr	Sun<=7	0:00	0	-
+Rule	Arg	1974	1976	-	Oct	Sun>=1	0:00	1:00	S
+Rule	Arg	1975	1977	-	Apr	Sun>=1	0:00	0	-
 Rule	Arg	1985	only	-	Nov	 2	0:00	1:00	S
 Rule	Arg	1986	only	-	Mar	14	0:00	0	-
 Rule	Arg	1986	1987	-	Oct	25	0:00	1:00	S
@@ -108,6 +108,15 @@ Rule	Arg	1989	1992	-	Oct	Sun>=15	0:00	1:
 # time corrections was derogated and no more modifications
 # to the time zones (for daylight saving) are now made.
 #
+# From Rives McDow (2000-01-10):
+# On October 3, 1999, 0:00 local, Argentina implemented daylight savings time,
+# which did not result in the switch of a time zone, as they stayed 9 hours
+# from the International Date Line.  On March 5, 2000, at 0:00 local time,
+# Argentina will come off daylight savings time, which will bring them to 8
+# hours from the International Date Line.
+Rule	Arg	1999	max	-	Oct	Sun>=1	0:00	1:00	S
+Rule	Arg	2000	max	-	Mar	Sun>=1	0:00	0	-
+#
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 #
 # Buenos Aires (BA), Distrito Federal (DF), Santa Cruz (SC),
@@ -115,26 +124,29 @@ Rule	Arg	1989	1992	-	Oct	Sun>=15	0:00	1:
 Zone America/Buenos_Aires -3:53:48 -	LMT	1894 Nov
 			-4:16:44 -	CMT	1920 May    # Cordoba Mean Time
 			-4:00	-	ART	1930 Dec
-			-4:00	Arg	AR%sT	1969 Oct 5
-			-3:00	Arg	AR%sT
+			-4:00	Arg	AR%sT	1969 Oct  5
+			-3:00	Arg	AR%sT	1999 Oct  3 0:00
+			-4:00	Arg	AR%sT
 #
 # Santa Fe (SF), Entre Rios (ER), Corrientes (CN), Misiones (MN), Chaco (CC),
 # Formosa (FM), La Pampa (LP), Chubut (CH)
 Zone America/Rosario	-4:02:40 -	LMT	1894 Nov
 			-4:16:44 -	CMT	1920 May
 			-4:00	-	ART	1930 Dec
-			-4:00	Arg	AR%sT	1969 Oct 5
+			-4:00	Arg	AR%sT	1969 Oct  5
 			-3:00	Arg	AR%sT	1991 Jul
-			-3:00	-	ART
+			-3:00	-	ART	1999 Oct  3 0:00
+			-4:00	Arg	AR%sT
 #
 # Cordoba (CB), Santiago del Estero (SE), Salta (SA), Tucuman (TM), La Rioja (LR), San Juan (SJ), San Luis (SL),
 # Neuquen (NQ), Rio Negro (RN)
 Zone America/Cordoba	-4:16:44 -	LMT	1894 Nov
 			-4:16:44 -	CMT	1920 May
 			-4:00	-	ART	1930 Dec
-			-4:00	Arg	AR%sT	1969 Oct 5
+			-4:00	Arg	AR%sT	1969 Oct  5
 			-3:00	Arg	AR%sT	1990 Jul
-			-3:00	-	ART
+			-3:00	-	ART	1999 Oct  3 0:00
+			-4:00	Arg	AR%sT
 #
 # Jujuy (JY)
 Zone America/Jujuy	-4:21:12 -	LMT	1894 Nov
@@ -145,17 +157,19 @@ Zone America/Jujuy	-4:21:12 -	LMT	1894 N
 			-4:00	-	WART	1991 Oct  6
 			-4:00	1:00	WARST	1992 Mar 15
 			-4:00	-	WART	1992 Oct 18
-			-3:00	-	ART
+			-3:00	-	ART	1999 Oct  3 0:00
+			-4:00	Arg	AR%sT
 #
 # Catamarca (CT)
 Zone America/Catamarca	-4:23:08 -	LMT	1894 Nov
 			-4:16:44 -	CMT	1920 May
 			-4:00	-	ART	1930 Dec
-			-4:00	Arg	AR%sT	1969 Oct 5
+			-4:00	Arg	AR%sT	1969 Oct  5
 			-3:00	Arg	AR%sT	1990 Jul
 			-3:00	-	ART	1991 Jul
 			-3:00	Arg	AR%sT	1992 Jul
-			-3:00	-	ART
+			-3:00	-	ART	1999 Oct  3 0:00
+			-4:00	Arg	AR%sT
 #
 # Mendoza (MZ)
 Zone America/Mendoza	-4:35:16 -	LMT	1894 Nov
@@ -166,7 +180,8 @@ Zone America/Mendoza	-4:35:16 -	LMT	1894
 			-4:00	-	WART	1991 Oct 15
 			-4:00	1:00	WARST	1992 Mar  1
 			-4:00	-	WART	1992 Oct 18
-			-3:00	-	ART
+			-3:00	-	ART	1999 Oct  3 0:00
+			-4:00	Arg	AR%sT
 
 # Aruba
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
@@ -411,7 +426,7 @@ Zone America/Porto_Acre	-4:31:12 -	LMT	1
 			-5:00	Brazil	AC%sT	1988 Sep 12
 			-5:00	-	ACT
 #
-# Martin Vaz and Trinidade are like America/Noronha.
+# Martin Vaz and Trindade are like America/Noronha.
 
 
 # Chile
@@ -545,7 +560,8 @@ Rule	Para	1996	only	-	Mar	 1	0:00	0	-
 Rule	Para	1997	only	-	Feb	lastSun	0:00	0	-
 Rule	Para	1998	only	-	Mar	 1	0:00	0	-
 Rule	Para	1996	max	-	Oct	Sun>=1	0:00	1:00	S
-# IATA SSIM (1999-02) says lastSat, not lastSun; go with Shanks.
+# IATA SSIM (1999-02) says lastSat, not lastSun; (1999-09) reports no date;
+# go with Shanks.
 Rule	Para	1999	max	-	Feb	lastSun	0:00	0	-
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone America/Asuncion	-3:50:40 -	LMT	1890
===================================================================
RCS file: RCS/WWW.htm,v
retrieving revision 1999.10
retrieving revision 1999.10.0.1
diff -pu -r1999.10 -r1999.10.0.1
--- WWW.htm	1999/11/13 19:27:44	1999.10
+++ WWW.htm	2000/01/11 07:46:46	1999.10.0.1
@@ -37,6 +37,16 @@ Here are some recent links that may be o
 <LI><A HREF="http://www.bsdi.com/date/">Date and Time Gateway</A>
 is a text-based source for tables of current time throughout the world.
 Its point-and-click interface accesses a recent version of the tz data.
+<LI><A
+HREF="http://www1.tip.nl/~t876506/AboutTimeZonesHC.html">HyperCard
+time zones calculator</A> is a <A
+HREF="http://www.apple.com/hypercard/">HyperCard</A> interface to a
+recent version of the tz data.
+<LI><A HREF="http://www.astro.ch/atlas/">Astrology / Astrologie -&gt;
+Astrodienst Atlas Database</A> is Astrodienst's Web version of <A
+HREF="http://www.astrocom.com/books/xrefa.htm#SHANKS">Shanks's
+excellent time zone history atlases</A> published by <A
+HREF="http://www.astrocom.com/">Astro Communications Services</A>.
 <LI><A HREF="http://worldtime.com/">WORLDTIME: interactive atlas,
 time info, public holidays</A>
 contains information on local time, sunrise and sunset,
@@ -62,7 +72,7 @@ and parts of the data are a few years ou
 has several fancy time zone maps; it covers Russia particularly well.
 The maps' pictorial quality is not quite as good as the CIA's
 and (as usual with maps) the maps are not quite up to date.
-<LI><A HREF="http://pisolo.cstv.to.cnr.it/toi/uk/toi.html">The
+<LI><A HREF="http://www.cstv.to.cnr.it/toi/uk/toi.html">The
 Time of Internet</A>
 contains good descriptions of Time Zones and daylight saving time,
 with diagrams.
@@ -70,9 +80,16 @@ The time zone map is out of date, howeve
 <LI><A HREF="http://ecco.bsee.swin.edu.au/chronos/GMT-explained.html">A
 Few Facts Concerning GMT, UT, and the RGO</A>
 answers questions like ``What is the difference between GMT and UTC?''
-<LI><A HREF="http://energy.ca.gov/daylightsaving.html">Daylight
-Saving Time -- Saving Time, Saving Energy</A>
-is a history of DST in the US.
+<LI><A
+HREF="http://sadira.gb.nrao.edu/~rfisher/Ephemerides/times.html">Astronomical
+Times</A> explains more abstruse astronomical time scales like TT, TCG,
+and TDB.
+<LI><A HREF="http://www.jpl.nasa.gov/basics/bsf2-3.htm">Earth
+and Its Reference Systems</A>
+briefly explains interplanetary space flight timekeeping.
+<LI><A HREF="http://www.webexhibits.com/daylightsaving/">Daylight
+Saving Time -- History, rationale, laws and dates</A>
+is a good history of DST.
 <LI><A HREF="http://dir.yahoo.com/Science/Measurements_and_Units/Time/Time_Zones/">Yahoo! - Science:Measurements and Units:Time:Time Zones</A>
 is where the famous Internet indexing service Yahoo! collects its time zone
 info.
@@ -87,7 +104,7 @@ when leap seconds occur.
 </UL>
 <P>
 -- <A HREF="mailto:eggert at twinsun.com">eggert at twinsun.com</A>
-(1999-03-22)
+(2000-01-10)
 </P>
 <H2>Arthur David Olson writes:</H2><P>
 A good source of information about
===================================================================
RCS file: RCS/zone.tab,v
retrieving revision 1999.10
retrieving revision 1999.10.0.1
diff -pu -r1999.10 -r1999.10.0.1
--- zone.tab	1999/11/13 19:27:45	1999.10
+++ zone.tab	2000/01/11 07:46:46	1999.10.0.1
@@ -234,7 +234,8 @@ MK	+4159+02126	Europe/Skopje
 ML	+1239-00800	Africa/Bamako	southwest Mali
 ML	+1446-00301	Africa/Timbuktu	northeast Mali
 MM	+1647+09610	Asia/Rangoon
-MN	+4755+10653	Asia/Ulan_Bator
+MN	+4755+10653	Asia/Ulaanbaatar	most locations
+MN	+4801+09139	Asia/Hovd	Bayan-Olgiy, Hovd, Uvs
 MO	+2214+11335	Asia/Macao
 MP	+1512+14545	Pacific/Saipan
 MQ	+1436-06105	America/Martinique
@@ -246,8 +247,9 @@ MV	+0410+07330	Indian/Maldives
 MW	-1547+03500	Africa/Blantyre
 MX	+1924-09909	America/Mexico_City	Central Time - most locations
 MX	+2105-08646	America/Cancun	Central Time - Quintana Roo
-MX	+2313-10625	America/Mazatlan	Mountain Time - most locations
+MX	+2313-10625	America/Mazatlan	Mountain Time - S Baja, Nayarit, Sinaloa
 MX	+2838-10605	America/Chihuahua	Mountain Time - Chihuahua
+MX	+2904-11058	America/Hermosillo	Mountain Standard Time - Sonora
 MX	+3232-11701	America/Tijuana	Pacific Time
 MY	+0310+10142	Asia/Kuala_Lumpur	peninsular Malaysia
 MY	+0133+11020	Asia/Kuching	Sabah & Sarawak



More information about the tz mailing list