February 2008 - tz - lists.iana.org

FW: when did China adopt one time zone?
by Olson, Arthur David (NIH/NCI) [E] Feb. 11, 2008

Feb. 11, 2008

I'm forwarding this message from Thomas S. Mullaney, who is not on the time zone mailing list. Those of you who are on the time zone mailing list should direct replies appropriately. --ado From: Thomas S. Mullaney [mailto:tsmullaney@stanford.edu] Sent: Friday, February 08, 2008 3:55 To: tz(a)lecserver.nci.nih.gov Subject: Re: when did China adopt one time zone? Dear Paul, Thanks for your email. The dating of "Beijing Time" is a little tricky, but thanks to Guo Qingsheng, a scholar and engineer at the Chinese Academy of Sciences Shaanxi Observatory, we know that the implementation of Beijing Time must have come after September 27, 1949 - the date on which the official name of Beiping (Northern Peace) was changed to Beijing (Northern Capital) - and some time before October 7 - the date of the earliest source which Guo has found containing the term "Beijing Time." This is a project I started thinking about this past summer - a fascinating topic, no? Sincerely, Tom Mullaney In a book review in today's issue of _Science_ you reported that the Chinese government in 1949 opted to observe one time zone. This caught my interest because I help maintain the tz database, which records histories of time zone and daylight saving changes all over the world. The tz database is used by computer clocks all over the world, including what I expect are millions of clocks in China, so I'd like to get the details right. Here's the problem: the tz database, following Shanks & Pottenger (2003), records that the China switched to a single time zone on May 1, 1980, not in 1949. Since you are a historian of China I expect that you have a lot better sources than we do. Can you please mention the sources for the claim that the clocks changed in 1949 rather than in 1980? Thanks for any info you can provide. I'll CC: this message to the tz database mailing list, to give them a heads-up on this query. -- Paul Eggert, UCLA Computer Science Dept. References: Thomas S. Mullaney, Change of time over changing time. Science 319 (5864), 729 (2008-02-08), DOI: 10.1126/science.1152851, <http://www.sciencemag.org/cgi/content/full/319/5864/729a>. Paul Eggert & Arthur David Olson, Sources for time zone and daylight saving time data <http://www.twinsun.com/tz/tz-link.htm> (2007-12-31); also see <http://en.wikipedia.org/wiki/Zoneinfo>. Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition). San Diego: ACS Publications, Inc. (2003). -- --- Thomas S. Mullaney Assistant Professor Modern Chinese History Department of History Stanford University 450 Serra Mall, Bld 200 Stanford, CA 94305-2024 T (650) 736-8386 F (650) 725-0597

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Atendimento online e Rastreador de visitantes
by Chat Comercial Feb. 11, 2008

Feb. 11, 2008

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FW: FW: Corrections to historic German timezone information
by Olson, Arthur David (NIH/NCI) [E] Feb. 11, 2008

Feb. 11, 2008

I'm forwarding this message from Sebastian Wangnick, who is not on the time zone mailing list (at least not at the address below). Those of you who are on the time zone mailing list should direct replies appropriately. --ado -----Original Message----- From: Sebastian Wangnick [mailto:sebastian.nospam01@wangnick.de] Sent: Monday, February 04, 2008 5:09 To: tz(a)lecserver.nci.nih.gov Subject: WG: FW: Corrections to historic German timezone information Dear all, it seems the email below did not reach the mailing list. Kind regards, Sebastian Wangnick -----Ursprüngliche Nachricht----- Von: Sebastian Wangnick [mailto:sebastian.nospam01@wangnick.de] Gesendet: Dienstag, 29. Januar 2008 19:18 An: 'Paul Eggert' Cc: 'tz(a)elsie.nci.nih.gov' Betreff: AW: FW: Corrections to historic German timezone information Dear Paul, I understand your concern. As proposed, the timezone Europe/Berlin would be applicable for the "western" countries of the state of Germany and the western part of Berlin, and Europe/BerlinEast for what was formerly first the Sowjet zone and later the state GDR, namely the "eastern" countries of the state of Germany (Mecklenburg-Vorpommern, Brandenburg, Sachsen, Sachsen-Anhalt, Thüringen) and the eastern part of Berlin. Creation of individual timezones for each of the countries of Germany is thus unneccessary. http://de.wikipedia.org/wiki/Bild:Deutschland_politisch_bunt.png However, if you can maintain only one timezone for the state of Germany, you should probably use the new definition of Europe/Berlin, limiting the error in 1945 to the smaller territory and population, but please note that this would be considered politically incorrect by said population. In this case we will privately maintain a modified copy of the tz database. Kind regards, Sebastian Wangnick

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when did China adopt one time zone?
by Paul Eggert Feb. 8, 2008

Feb. 8, 2008

In a book review in today's issue of _Science_ you reported that the Chinese government in 1949 opted to observe one time zone. This caught my interest because I help maintain the tz database, which records histories of time zone and daylight saving changes all over the world. The tz database is used by computer clocks all over the world, including what I expect are millions of clocks in China, so I'd like to get the details right. Here's the problem: the tz database, following Shanks & Pottenger (2003), records that the China switched to a single time zone on May 1, 1980, not in 1949. Since you are a historian of China I expect that you have a lot better sources than we do. Can you please mention the sources for the claim that the clocks changed in 1949 rather than in 1980? Thanks for any info you can provide. I'll CC: this message to the tz database mailing list, to give them a heads-up on this query. -- Paul Eggert, UCLA Computer Science Dept. References: Thomas S. Mullaney, Change of time over changing time. Science 319 (5864), 729 (2008-02-08), DOI: 10.1126/science.1152851, <http://www.sciencemag.org/cgi/content/full/319/5864/729a>. Paul Eggert & Arthur David Olson, Sources for time zone and daylight saving time data <http://www.twinsun.com/tz/tz-link.htm> (2007-12-31); also see <http://en.wikipedia.org/wiki/Zoneinfo>. Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition). San Diego: ACS Publications, Inc. (2003).

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WG: FW: Corrections to historic German timezone information
by Sebastian Wangnick Feb. 4, 2008

Feb. 4, 2008

Dear all, it seems the email below did not reach the mailing list. Kind regards, Sebastian Wangnick -----Ursprüngliche Nachricht----- Von: Sebastian Wangnick [mailto:sebastian.nospam01@wangnick.de] Gesendet: Dienstag, 29. Januar 2008 19:18 An: 'Paul Eggert' Cc: 'tz(a)elsie.nci.nih.gov' Betreff: AW: FW: Corrections to historic German timezone information Dear Paul, I understand your concern. As proposed, the timezone Europe/Berlin would be applicable for the "western" countries of the state of Germany and the western part of Berlin, and Europe/BerlinEast for what was formerly first the Sowjet zone and later the state GDR, namely the "eastern" countries of the state of Germany (Mecklenburg-Vorpommern, Brandenburg, Sachsen, Sachsen-Anhalt, Thüringen) and the eastern part of Berlin. Creation of individual timezones for each of the countries of Germany is thus unneccessary. http://de.wikipedia.org/wiki/Bild:Deutschland_politisch_bunt.png However, if you can maintain only one timezone for the state of Germany, you should probably use the new definition of Europe/Berlin, limiting the error in 1945 to the smaller territory and population, but please note that this would be considered politically incorrect by said population. In this case we will privately maintain a modified copy of the tz database. Kind regards, Sebastian Wangnick

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Re: FW: Corrections to historic German timezone information
by Paul Schauble Feb. 4, 2008

Feb. 4, 2008

It might be easier to acknowledge the west/east Berlin split than to figure out which single rule is better. The problem I see is that in reality the presnt day Berlin and the historic Berlin did not exist for 40 years. I am not sure this can be ignored. ++PLS ----- Original Message ----- From: Markus Scherer <markus.icu(a)gmail.com> To: tz(a)lecserver.nci.nih.gov <tz(a)lecserver.nci.nih.gov> Cc: Sebastian Wangnick <sebastian.nospam01(a)wangnick.de>; tz(a)lecserver.nci.nih.gov <tz(a)lecserver.nci.nih.gov> Sent: Sun Feb 03 15:58:24 2008 Subject: Re: FW: Corrections to historic German timezone information On Jan 28, 2008 3:59 PM, Paul Eggert <eggert(a)cs.ucla.edu> wrote: > Because of this rule, the 1945 divergence doesn't justify having two > separate entries for Berlin. However, we should have the correct > entry for Berlin, which raises the question: where is the commonly > accepted center of Berlin? If the center is in the former Soviet > zone, tz's Europe/Berlin should use what is in the proposed > Europe/BerlinEast zone. If Berlin's center is in the former > west-Berlin zone, Europe/Berlin should change to match what is in the > proposed Europe/Berlin zone. I don't quite understand this. I do understand that it's overkill from the perspective of the TZ maintainers to precisely distinguish pre-1970 transitions, but it seems like the question of which part of Berlin to use should not depend as much on where the city center is but on the political continuity. markus -- Opinions expressed here may not reflect my company's positions unless otherwise noted.

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FW: Corrections to historic German timezone information
by Olson, Arthur David (NIH/NCI) [E] Feb. 3, 2008

Feb. 3, 2008

I'm forwarding this message from Sebastian Wangnick, who is not on the time zone mailing list. Those of you who are on the time zone mailing list should direct replies appropriately. --ado From: Sebastian Wangnick [mailto:sebastian.nospam01@wangnick.de] Sent: Sunday, January 27, 2008 2:02 To: tz(a)lecserver.nci.nih.gov Cc: time(a)ptb.de Subject: Corrections to historic German timezone information Dear Madam, dear Sir, I understand that the historic time zone database you maintain is the basis of calendar computations in many computer systems and programming languages, including Linux and Tcl. We are using said data in some of our applications. Many thanks for your effort. Please find attached a few modifications to your tz2007k data files, so as to bring them in line with the publications of the Arbeitsgruppe 4.41 of the Physikalisch-Technische Bundesanstalt at http://www.ptb.de/de/org/4/44/441/salt.htm. The mistake in tz2007k is that the special 1945 rules for East Berlin and the German Sowjet Zone mentioned in bullet point c) of the website above are applied to Germany in general. The modifications return Europe/Berlin to the standard rules a) and b), and introduce a new zone Europe/BerlinEast where a), b) and c) are applied. Cc to the PTB for information. Kind regards, Sebastian Wangnick -- Sebastian Wangnick Lammersdorfer Str. 61 D-52159 Roetgen/Rott

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Fw: GUATEMALA from DST 30 APR to 29 SEP 2008
by Gwillim Law Feb. 3, 2008

Feb. 3, 2008

Risto Nykänen wrote me that Guatemala is going to observe DST from 2008-04-30 to 2008-09-29. Searching for confirmation, I found an article at http://www.prensalibre.com/pl/2008/enero/29/217165.html, apparently from a Guatemalan newspaper. It says: "El Gobierno guatemalteco adelantará la hora oficial en a partir del 30 de abril en un intento por reducir la demanda de energía eléctrica. "'Ya es un hecho, se va a cambiar a finales de abril para tener horario de verano', dijo el vocero presidencial Fernando Barillas. "Con la medida el ejecutivo espera obtener un ahorro de 60 megavatios diarios entre el 30 de abril y el 30 de septiembre, cuando termine el horario especial. ..." My translation: "The Guatemalan government will advance official time starting on April 30 in an initiative to reduce demand for electrical energy. "'It is already a done deed, we are going to change at the end of April to observe summer time', the presidential spokesman Fernando Barillas said. "With this measure the executive hopes to save 60 megawatts a day between April 30 and September 30, when the special schedule ends." Gwillim Law

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