From b724c2f69699a629a196fd997ea3c5b9fae6ab32 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Tue, 15 Jul 2014 21:58:31 -0700 Subject: A few more changes for consistency. * africa (Africa/Accra): Assume DST starting in 1920, as per Scott Keltie & Epstein 1920. * asia (Asia/Riyadh): Change standard-time transition from 1950 to 1947-03-14. Add commentary citing Hunt 1961 and CAB 1946. * australasia (Pacific/Chatham): Assume NZST - 45 min. before 1946. Add commentary about this. (Pacific/Pago_Pago): UT-11 from 1911 to 1950. (WS, Pacific/Apia): Use NZ-style abbreviations. Switch to "WSST" for Western Samoa standard time before 1950. Add commentary about Samoa before 1950. * NEWS: Document the above. (cherry picked from commit f1ddf32f059c17fa5a1ec24f549d70db36dc5fa9) --- NEWS | 16 ++++++++++++++++ africa | 10 +++++++--- asia | 23 ++++++++++++++++++++++- australasia | 40 ++++++++++++++++++++++++++++++++-------- 4 files changed, 77 insertions(+), 12 deletions(-) diff --git a/NEWS b/NEWS index ce2e33a..e87c519 100644 --- a/NEWS +++ b/NEWS @@ -40,6 +40,11 @@ Unreleased, experimental changes Prefer MSK/MSD for Moscow time in Russia, even in other cities. Similarly, prefer EET/EEST for eastern European time in Russia. + Change time zone abbreviations in (western) Samoa to use "ST" and + "DT" suffixes, as this is more likely to match common practice. + Prefix "W" to (western) Samoa time when its standard-time offset + disagrees with that of American Samoa. + Time zone abbreviations have been updated for Japan's two time zones used 1896-1937. JWST now stands for Western Standard Time, and JCST for Central Standard Time (formerly this was CJT). @@ -67,9 +72,20 @@ Unreleased, experimental changes from 04-15 through 10-31; and in 1979 from 07-01 through 09-30. (Thanks to Yu-Cheng Chuang.) + Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950. + Europe/Helsinki's 1942 fall-back transition was October 4 at 01:00, not October 3 at 00:00. (Thanks to Konstantin Hyppönen.) + Pacific/Pago_Pago has been changed from UTC-11:30 to UTC-11 for the period + from 1911 to 1950. + + Pacific/Chatham has been changed to New Zealand standard time plus + 45 minutes for the period before 1957, reflecting a 1956 remark in + the New Zealand parliament. + + Africa/Accra is now assumed to have observed DST from 1920 through 1935. + Time in Russia before 1927 or so has been corrected by a few seconds in the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi, Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and diff --git a/africa b/africa index 3d84d9b..e4ba52b 100644 --- a/africa +++ b/africa @@ -437,9 +437,13 @@ Zone Africa/Banjul -1:06:36 - LMT 1912 # Ghana # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S # Whitman says DST was observed from 1931 to "the present"; -# go with Shanks & Pottenger. -Rule Ghana 1936 1942 - Sep 1 0:00 0:20 GHST -Rule Ghana 1936 1942 - Dec 31 0:00 0 GMT +# Shanks & Pottenger say 1936 to 1942; +# and September 1 to January 1 is given by: +# Scott Keltie J, Epstein M (eds), The Statesman's Year-Book, +# 57th ed. Macmillan, London (1920), OCLC 609408015, pp xxviii. +# For lack of better info, assume DST was observed from 1920 to 1942. +Rule Ghana 1920 1942 - Sep 1 0:00 0:20 GHST +Rule Ghana 1920 1942 - Dec 31 0:00 0 GMT # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Africa/Accra -0:00:52 - LMT 1918 0:00 Ghana %s diff --git a/asia b/asia index 4d9faeb..148671c 100644 --- a/asia +++ b/asia @@ -2439,8 +2439,29 @@ Zone Asia/Qatar 3:26:08 - LMT 1920 # Al Dawhah / Doha 3:00 - AST # Saudi Arabia +# +# From Paul Eggert (2014-07-15): +# Time in Saudi Arabia and other countries in the Arabian peninsula was not +# standardized until relatively recently; we don't know when, and possibly it +# has never been made official. Richard P Hunt, in "Islam city yielding to +# modern times", New York Times (1961-04-09), p 20, wrote that only airlines +# observed standard time, and that people in Jidda mostly observed quasi-solar +# time, doing so by setting their watches at sunrise to 6 o'clock (or to 12 +# o'clock for "Arab" time). +# +# The TZ database cannot represent quasi-solar time; airline time is the best +# we can do. The 1946 foreign air news digest of the U.S. Civil Aeronautics +# Board (OCLC 42299995) reported that the "... Arabian Government, inaugurated +# a weekly Dhahran-Cairo service, via the Saudi Arabian cities of Riyadh and +# Jidda, on March 14, 1947". Shanks & Pottenger guessed 1950; go with the +# earlier date. +# +# Shanks & Pottenger also state that until 1968-05-01 Saudi Arabia had two +# time zones; the other zone, at UTC+4, was in the far eastern part of +# the country. Ignore this, as it's before our 1970 cutoff. +# # Zone NAME GMTOFF RULES FORMAT [UNTIL] -Zone Asia/Riyadh 3:06:52 - LMT 1950 +Zone Asia/Riyadh 3:06:52 - LMT 1947 Mar 14 3:00 - AST # Singapore diff --git a/australasia b/australasia index 605d8dd..4911e8d 100644 --- a/australasia +++ b/australasia @@ -466,7 +466,8 @@ Rule Chatham 2008 max - Apr Sun>=1 2:45s 0 S Zone Pacific/Auckland 11:39:04 - LMT 1868 Nov 2 11:30 NZ NZ%sT 1946 Jan 1 12:00 NZ NZ%sT -Zone Pacific/Chatham 12:13:48 - LMT 1957 Jan 1 +Zone Pacific/Chatham 12:13:48 - LMT 1868 Nov 2 + 12:15 - CHAST 1946 Jan 1 12:45 Chatham CHA%sT Link Pacific/Auckland Antarctica/McMurdo @@ -528,7 +529,6 @@ Zone Pacific/Pitcairn -8:40:20 - LMT 1901 # Adamstown # American Samoa Zone Pacific/Pago_Pago 12:37:12 - LMT 1879 Jul 5 -11:22:48 - LMT 1911 - -11:30 - SAMT 1950 # Samoa Time -11:00 - NST 1967 Apr # N=Nome -11:00 - BST 1983 Nov 30 # B=Bering -11:00 - SST # S=Samoa @@ -603,15 +603,15 @@ Zone Pacific/Pago_Pago 12:37:12 - LMT 1879 Jul 5 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule WS 2010 only - Sep lastSun 0:00 1 D -Rule WS 2011 only - Apr Sat>=1 4:00 0 - +Rule WS 2011 only - Apr Sat>=1 4:00 0 S Rule WS 2011 only - Sep lastSat 3:00 1 D -Rule WS 2012 max - Apr Sun>=1 4:00 0 - +Rule WS 2012 max - Apr Sun>=1 4:00 0 S Rule WS 2012 max - Sep lastSun 3:00 1 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Pacific/Apia 12:33:04 - LMT 1879 Jul 5 -11:26:56 - LMT 1911 - -11:30 - SAMT 1950 # Samoa Time - -11:00 WS WS%sT 2011 Dec 29 24:00 + -11:30 - WSST 1950 + -11:00 WS S%sT 2011 Dec 29 24:00 # S=Samoa 13:00 WS WS%sT # Solomon Is @@ -804,7 +804,10 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901 # 10:30 LHST LHDT Lord Howe* # 11:30 NZMT NZST New Zealand through 1945 # 12:00 NZST NZDT New Zealand 1946-present -# 12:45 CHAST CHADT Chatham* +# 12:15 CHAST Chatham through 1945* +# 12:45 CHAST CHADT Chatham 1946-present* +# 13:00 WSST WSDT (western) Samoa 2011-present* +# -11:30 WSST Western Samoa through 1950* # -11:00 SST Samoa # -10:00 HST Hawaii # - 8:00 PST Pitcairn* @@ -1429,6 +1432,19 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901 # that DST will begin on 2007-09-30 2008-04-06. # http://www.dia.govt.nz/diawebsite.nsf/wpg_URL/Services-Daylight-Saving-Daylight-saving-to-be-extended +# From Paul Eggert (2014-07-14): +# Chatham Island time was formally standardized on 1957-01-01 by +# New Zealand's Standard Time Amendment Act 1956 (1956-10-26) +# . +# According to Google Books snippet view, a speaker in the New Zealand +# parliamentary debates in 1956 said "Clause 78 makes provision for standard +# time in the Chatham Islands. The time there is 45 minutes in advance of New +# Zealand time. I understand that is the time they keep locally, anyhow." +# For now, assume this practice goes back to the introduction of standard time +# in New Zealand, as this would make Chatham Islands time almost exactly match +# LMT back when New Zealand was at UTC+11:30; also, assume Chatham Islands did +# not observe New Zealand's prewar DST. + ############################################################################### @@ -1546,7 +1562,7 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901 # Sacramento but it was changed a couple of years ago. -# Samoa +# (Western) Samoa and American Samoa # Howse writes (p 153, citing p 10 of the 1883-11-18 New York Herald) # that in 1879 the King of Samoa decided to change @@ -1554,6 +1570,14 @@ 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." +# Although Shanks & Pottenger says they both switched to UTC-11:30 +# in 1911, and to UTC-11 in 1950. many earlier sources give UTC-11 +# for American Samoa, e.g., the US National Bureau of Standards +# circular "Standard Time Throughout the World", 1932. +# Assume American Samoa switched to UTC-11 in 1911, not 1950, +# and that after 1950 they agreed until (western) Samoa skipped a +# day in 2011. Assume also that the Samoas follow the US and New +# Zealand's "ST"/"DT" style of daylight-saving abbreviations. # Tonga -- 1.7.9