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Cuba back on standard time
by mike castleman Oct. 31, 2006

Oct. 31, 2006

According to _Granma_, the official newspaper: AT 1:00 a.m. on Sunday, October 29, the clocks in Cuba were put back one hour, thus standard time – also known as winter time – in Cuba has once more come into effect. [...] full article (english): http://www.granma.cu/ingles/2006/octubre/lun30/45hora.html (spanish): http://www.granma.cu/espanol/2006/octubre/vier27/horario-e.html The Spanish article is clearer than the English that the change took place at 1am summer time; i.e., midnight standard time.

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Chile DST history
by Jesper Norgaard Welen Oct. 31, 2006

Oct. 31, 2006

The page http://www.worldtimeserver.com claims that Chile starts DST this Sunday 8.th. of October at 1:00 so I got interested in if we have the information right concerning Chile. This made me revise the information in the tz database, which lead to the page http://www.shoa.cl which represents the oficial timekeeping of the armed forces of Chile, which in turn is the only authority on time setting matters in Chile since 11.th. of January 1966 according to decree No. 25 of that year. CIA factbook says on page http://www.cia.gov/cia/publications/factbook/geos/ci.html that DST starts second Sunday in October, ends Second Sunday of March. But according to the official page it is really Second Saturday of October at 24:00 and Second Saturday of March at 24:00. 2006 happens to be a year where these two rules get to different results, in fact DST begins in Chile in 2006 Saturday 14.th. of March at 24:00, according to one of the Chile web pages. In tz database, file southamerica says: # From Paul Eggert (2002-10-24): # <http://www.shoa.cl/shoa/faqhoraoficial.htm> gives many details that # disagree with the following table, but we haven't had time to compare them. As far as I see it, this is the maximum authority of time setting in Chile, which should supersede tz database, Shanks, IATA etc. If you disagree on this point, please forward good arguments. Therefore I recommend the following changes to the tz database. I took the time to check out in detail what the differences are from this source compared to tz database, based on the page http://www.horaoficial.cl/horaof.htm which contains timezone and time history in Chile since 1884. Here are the results if you apply those to the tz database (I might have made mistakes, since there are plenty of differences): # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Chile 1927 1931 - Sep 1 0:00 1:00 S Rule Chile 1928 1932 - Apr 1 0:00 0 - Rule Chile 1946 only - Aug 27 4:00u 1:00 S Rule Chile 1947 only - May 21 2:00u 0 - Rule Chile 1968 only - Nov 2 4:00u 1:00 S Rule Chile 1969 only - Mar 29 3:00u 0 - Rule Chile 1969 only - Nov 22 4:00u 1:00 S Rule Chile 1970 only - Mar 28 3:00u 0 - Rule Chile 1971 only - Mar 13 3:00u 0 - Rule Chile 1970 1972 - Oct Sun>=9 4:00u 1:00 S Rule Chile 1973 only - Sep 29 4:00u 1:00 S Rule Chile 1972 1986 - Mar Sun>=9 3:00u 0 - Rule Chile 1974 1987 - Oct Sun>=9 4:00u 1:00 S Rule Chile 1987 only - Apr 12 3:00u 0 - Rule Chile 1988 only - Oct Sun>=1 4:00u 1:00 S Rule Chile 1988 1989 - Mar Sun>=9 3:00u 0 - Rule Chile 1989 only - Oct Sun>=9 4:00u 1:00 S Rule Chile 1990 only - Mar 18 3:00u 0 - Rule Chile 1990 only - Sep 16 4:00u 1:00 S Rule Chile 1991 1996 - Mar Sun>=9 3:00u 0 - Rule Chile 1991 1997 - Oct Sun>=9 4:00u 1:00 S Rule Chile 1997 only - Mar 30 3:00u 0 - Rule Chile 1998 only - Sep 27 4:00u 1:00 S Rule Chile 1998 only - Mar Sun>=9 3:00u 0 - Rule Chile 1999 only - Apr 4 3:00u 0 - Rule Chile 1999 max - Oct Sun>=9 4:00u 1:00 S Rule Chile 2000 max - Mar Sun>=9 3:00u 0 - # IATA SSIM anomalies: (1992-02) says 1992-03-14; # (1996-09) says 1998-03-08. Ignore these. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Santiago -4:42:40 - LMT 1890 -4:42:40 - SMT 1910 Jan 10 # Santiago Mean Time -5:00 - CL%sT 1916 Jul 1 # Chile Time -4:42:46 - SMT 1918 Sep 10 # Santiago Mean Time -4:00 - CL%sT 1919 Jul 1 # Chile Time -4:42:46 - SMT 1927 Aug 22 # Santiago Mean Time -5:00 Chile CL%sT 1932 Sep # Chile Time -4:00 Chile CL%sT Zone Pacific/Easter -7:17:28 - LMT 1890 # Mataveri -7:17:28 - MMT 1932 Sep # Mataveri Mean Time -7:00 Chile EAS%sT 1982 Jan 18 21:00 # Easter I Time -6:00 Chile EAS%sT Note (1) Since the starting and ending of DST in 1927-1932 is a bit confusing (not covered by a decree of when it ended), I used the tz database as it was, since the first two transitions concur with the web page. It seems that the Chile web page claims that it stopped in 1928, but it doesn't mention a decree about that. Note (2) The DST employment in 1946-1947 was decreed only for the central zone (whatever that is, but surely including Santiago), not for the rest of the country. But since this happens before our cutoff date of 1970, there is no need to make an extra timezone. Note (3) Since one of the IATA anomalies were agreeing with the Chile page, I deleted that from the commentary. I also did not put commentary for if the above changes are accepted (like "Jesper Norgaard wrote ..."), I will leave that happily to whoever might implement it in a coming version of the tz database. Regards, - Jesper Jesper Nørgaard Welen Email: jnorgard(a)Prodigy.Net.mx Project Leader (Líder de Proyecto) Software CIMMYT - Centro Internacional de Mejoramiento de Maíz y Trigo Dirección: CIMMYT Int. c/o Jesper Nørgaard Km. 45, Carretera México-Veracruz El Batán Texcoco, Edo. de México CP 56130 MEXICO Tel.: +52 (55) 58-04-20-04 ext. 1374 Fax: +52 (55) 58-04-75-58 Tel. Casa: 53-10-05-95 ó 53-10-97-78 Download the shareware program World Time Explorer, I made: http://www.worldtimeexplorer.com/index.html

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Paraguay link update
by Jesper Norgaard Welen Oct. 31, 2006

Oct. 31, 2006

I contacted Carlos Raúl Perasso from Paraguay, if there was news about the expected change this Sunday to DST in Paraguay. He tells me that the originally scheduled change will happen as planned, and gave me an official link: http://www.presidencia.gov.py/decretos/D1867.pdf The link in the 'southamerica' file is outdated (that happens often), which was Steffen's link from 2004-03-05 <http://www.labor.com.py/noticias.asp?id=27>, note that also my link from 2001-03-06 is outdated: # From Jesper Norgaard (2001-03-06) [an official URL saying similar things]: # http://gateway.abc.com.py:8000/pub/pag04.mbr/artic?FHA=2001-03-03-02.24.52.9 00592 # ... # From Steffen Thorsen (2005-01-05): # Decree 1,867 (2004-03-05) <http://www.labor.com.py/noticias.asp?id=27> The new link from Carlos is also containing decree 1,867. Carlos asks me that his email information in the tz emailing list be updated to crperasso(a)gmail.com Regards, - Jesper Nørgaard Welen Jesper Nørgaard Welen Email: jnorgard(a)Prodigy.Net.mx Project Leader (Líder de Proyecto) Software CIMMYT - Centro Internacional de Mejoramiento de Maíz y Trigo Dirección: CIMMYT Int. c/o Jesper Nørgaard Km. 45, Carretera México-Veracruz El Batán Texcoco, Edo. de México CP 56130 MEXICO Tel.: +52 (55) 58-04-20-04 ext. 1374 Fax: +52 (55) 58-04-75-58 Tel. Casa: 53-10-05-95 ó 53-10-97-78 Download the shareware program World Time Explorer, I made: http://www.worldtimeexplorer.com/index.html

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Corrections to latitudes/longitudes in zone.tab
by Andy McDonald Oct. 31, 2006

Oct. 31, 2006

Hi, I've run across a couple of inaccurate latitudes/longitudes in tz's zone.tab (2006n): Approx true lat/long zone.tab lat/long Europe/Jersey +4912-00207 +4912-00237 Europe/Podgorica +4227+01916 +4247+01928 Jersey perhaps looks like a typo.; Podgorica's latitude looks like a typo., but not the longitude. The corrected values come from playing with my Firefox time zone extension (http://www.stemhaus.com/firefox/foxclocks/) and Google Earth, and are of course entirely subjective. Regards, Andy McDonald

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FW: tz database help
by Olson, Arthur David (NIH/NCI) [E] Oct. 30, 2006

Oct. 30, 2006

I'm forwarding this message from Joseph Thurakal, who is not on the time zone mailing list. Those of you who are on the time zone mailing list: please direct replies appropriately. JT: the idea if you're writing a C language program is to set the time zone environment variable to the value associated with the US central time zone location of interest, fill in a "struct tm" with the values associated with the instant of interest, call "mktime" to find the "time_t" value associated with the filled-in structure, then re-set the time zone enviroment variable to the appropriate "another time zone" value and feed mktime's returned time_t value to "localtime." --ado ________________________________ From: Joseph Thurakal [mailto:josephthurakal@gmail.com] Sent: Friday, October 27, 2006 7:55 AM To: tz(a)lecserver.nci.nih.gov Subject: tz database help Hi, My name is Joseph Thurakal and I am new to tz database. I am trying to figure out how to convert historic US central time zone times into another time zone, and I can't figure this out from the readme files. Could you outline how to do this or point me to a good source? Thanks for your help. Joe

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tz database help
by Joseph Thurakal Oct. 27, 2006

Oct. 27, 2006

Hi, My name is Joseph Thurakal and I am new to tz database. I am trying to figure out how to convert historic US central time zone times into another time zone, and I can't figure this out from the readme files. Could you outline how to do this or point me to a good source? Thanks for your help. Joe

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One letter change in tz data
by Jesper Norgaard Welen Oct. 26, 2006

Oct. 26, 2006

There is news about the revival of DST in Cuba (after 3 years of inactivity). An article in GRANMA INTERNACIONAL claims that Cuba will end the 3 years of permanent DST next weekend, see http://www.granma.cu/ingles/2006/octubre/lun16/43horario.html (note there are both spanish and english versions of this article). A few quotes: "AFTER three years of remaining on a summer daylight savings time schedule, Cubas National Electrical Union decided to go back to its normal schedule during this month of October. On Saturday night, October 28 going into Sunday, October 29, at 01:00 , watches should be set back one hour going back to 00:00 hours returning to the normal schedule, which in Cuba is known as the winter schedule ... In Cuba, because of electricity generation shortages, it was decided to maintain the summer daylight savings schedule for three years; however, the country is now in a position to produce all the energy it needs, which is why it was decided to go back to the regular schedule." We are in the lucky position to be able to change this with a single letter change, from "7" to "6": -Rule Cuba 2007 max - Oct lastSun 0:00s 0 S +Rule Cuba 2006 max - Oct lastSun 0:00s 0 S Regards, Jesper Jesper Nørgaard Welen Email: jnorgard(a)Prodigy.Net.mx Project Leader (Líder de Proyecto) Software CIMMYT - Centro Internacional de Mejoramiento de Maíz y Trigo Dirección: CIMMYT Int. c/o Jesper Nørgaard Km. 45, Carretera México-Veracruz El Batán Texcoco, Edo. de México CP 56130 MEXICO Tel.: +52 (55) 58-04-20-04 ext. 1374 Fax: +52 (55) 58-04-75-58 Tel. Casa: 53-10-05-95 ó 53-10-97-78 Download the shareware program World Time Explorer, I made: http://www.worldtimeexplorer.com/index.html

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DST in West Australia?
by Jesper Norgaard Welen Oct. 25, 2006

Oct. 25, 2006

These four links talk about DST as a possibility in Queensland and West Australia: http://origin.theaustralian.news.com.au/story/0,20867,20642132-5006789,00.ht ml http://origin.theaustralian.news.com.au/story/0,20867,20640810-5006789,00.ht ml http://origin.theaustralian.news.com.au/story/0,20867,20637822-5006789,00.ht ml http://origin.theaustralian.news.com.au/story/0,20867,20635587-5006789,00.ht ml The status quo at the moment seems to be that Queensland will stay with no DST, while West Australia is likely to approve a three year trial, beginning DST December 1, 2006, outside the schedule of any other state of Australia (mainland states that use DST are in-synch, while Tasmania and Lord Howe Island have their own variations of DST). There are apparently two bills which might be merged into one. Anyways, for the moment there are no definitive decisions yet, although it seems an individual count of MPs votes in West Australia favor the approval of the new DST. Stay tuned! Regards, - Jesper Jesper Nørgaard Welen Email: jnorgard(a)Prodigy.Net.mx Project Leader (Líder de Proyecto) Software CIMMYT - Centro Internacional de Mejoramiento de Maíz y Trigo Dirección: CIMMYT Int. c/o Jesper Nørgaard Km. 45, Carretera México-Veracruz El Batán Texcoco, Edo. de México CP 56130 MEXICO Tel.: +52 (55) 58-04-20-04 ext. 1374 Fax: +52 (55) 58-04-75-58 Tel. Casa: 53-10-05-95 ó 53-10-97-78 Download the shareware program World Time Explorer, I made: http://www.worldtimeexplorer.com/index.html

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FW: Beijing Time?
by Olson, Arthur David (NIH/NCI) [E] Oct. 24, 2006

Oct. 24, 2006

I'm forwarding this message from Emma Baillie, who is not on the time zone mailing list. Those of you who are on the list should direct replies appropriately. (Emma Baillie: within... ftp://elsie.nci.nih.gov/pub/tzcode2006n.tar.gz ...there's a "Theory" file explaining the principles behind naming zones. Shanghai is used because it's the most populous city--at least by some measures--in the time zone of interest. Note that the eastern United States time zone where I live is known as "America/New_York" and not "America/Washington"--we're not singling out China for different treatment.) --ado -----Original Message----- From: Emma Baillie [mailto:ebaillie@aconex.com] Sent: Monday, October 23, 2006 2:19 AM To: tz(a)lecserver.nci.nih.gov Subject: Beijing Time? My workplace has recently included data form the tz database into our web services, which are used in various different countries around the world including (recently) China. Our Chinese customers are quite unhappy about the fact that their timezone is specified as "Asia/Shanghai" not "Asia/Beijing". As one customer commented: "Every one knows whole china has only one time zone which was officially named Beijing Time Zone, My client told me that Chinese people really can not understand why we missed our Capital City Time Zone on the list. They think it is disrespectful." I see from the official Chinese government website, that this also refers to the Chinese time zone as "Beijing Time" http://english.gov.cn/2005-08/25/content_26048.htm. I'm wondering if there is any reason (other than historical) to continue to refer to the time zone in China as "Asia/Shanghai". Should it not be updated to reflect current Chinese usage? Of course, in my own particular instance I can simply change it in our application (and will!) But this seems like a change which would be more generally useful. thanks emma baillie

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Beijing Time?
by Emma Baillie Oct. 23, 2006

Oct. 23, 2006

My workplace has recently included data form the tz database into our web services, which are used in various different countries around the world including (recently) China. Our Chinese customers are quite unhappy about the fact that their timezone is specified as "Asia/Shanghai" not "Asia/Beijing". As one customer commented: "Every one knows whole china has only one time zone which was officially named Beijing Time Zone, My client told me that Chinese people really can not understand why we missed our Capital City Time Zone on the list. They think it is disrespectful." I see from the official Chinese government website, that this also refers to the Chinese time zone as "Beijing Time" http://english.gov.cn/2005-08/25/content_26048.htm. I'm wondering if there is any reason (other than historical) to continue to refer to the time zone in China as "Asia/Shanghai". Should it not be updated to reflect current Chinese usage? Of course, in my own particular instance I can simply change it in our application (and will!) But this seems like a change which would be more generally useful. thanks emma baillie

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