Talk:Daylight saving time by country/Archive 1

Why in Israel part mention Palestinian as Terrorist ? edit

Why in Israel part mention Palestinian as Terrorist ? it just mention for political issues , its not related to the core subject ! —Preceding unsigned comment added by 82.205.46.2 (talk) 22:29, 3 May 2011 (UTC)Reply

→ I removed that part. If you know any source about information of DST there, will be great. Thanks.Malekobaid (talk) 22:53, 27 October 2012 (UTC)Reply

World War I daylight saving in Austria-Hungary edit

Austria-Hungary introduced daylight saving in 1916 and used it until the end of the First World War in 1918. I've updated the list to ensure that several modern countries that were then a part of Austria-Hungary record this fact. The countries updated are: Bosnia-Hercegovina, Croatia and Slovenia. — Preceding unsigned comment added by 202.0.15.181 (talk) 04:13, 5 October 2016 (UTC)Reply


Why is not USA first? edit

The countries should be listed by order of importance.--Dubucucupupurugallogo (talk) 21:41, 6 March 2009 (UTC)Reply

I think that's possibly the most ridiculous comment I've ever seen on Wikipedia. Congratulations. Martin (talk) 01:56, 8 March 2009 (UTC)Reply

Rename your country with something that begins with the letter "A" and then it will be first. Perhaps something like Aardvark? Good luck getting it through Congress.

Perhaps if we ranked the country in order of greatest number of Wikipedia users, the problem would resolve itself?

John Paul Parks (talk) 01:25, 21 July 2009 (UTC)Reply

America. 74.42.183.36 (talk) 04:01, 5 November 2013 (UTC)Reply

Emm... America is a continent with more than 30 countries, maybe you should read more before comment. --Cancuen (talk) 07:30, 2 September 2015 (UTC)Reply

Yes, but 9.5 times out of 10, America refers to the United States Donnellan0007 (talk) 13:12, 5 October 2021 (UTC)Reply
[citation needed] I suspect sampling bias. The Crab Who Played With The Sea (talk) 12:39, 23 November 2021 (UTC)Reply

Article expansion edit

epand this aritile within 5 days Jer10 95 21:40, 10 November 2006 (UTC)Reply

Why was this article created without a consensus to split it off of Daylight saving time? In addition, it's pretty long as it is; does it really need an expansion tag? - BillCJ 15:11, 26 November 2006 (UTC)Reply

Merge proposal edit

Assuming that this article remains, I propose that List of countries that do not observe Daylight Saving Time be merged here. There was an expansion tag on that short article. Its content would fit perfectly here. - BillCJ 15:28, 26 November 2006 (UTC)Reply

Split off of Daylight Saving Time performed. Merge from List of countries that do not observe Daylight Saving Time completed. I will try to integrate the two separate sections, using the continents and the major headings. - BillCJ 06:17, 1 December 2006 (UTC)Reply

US time zone table edit

This table was in the Halloween section, where I couldn't figure out what it was supposed to mean. I moved it to the 2006 section, since that's the rule set that it uses to calculate the current time in the various time zones.

I have to wonder whether the "current time" aspect of this table is really useful. It's a maintenance nuisance (over in the template, of course), since it has to be updated when the rules change. John Rotunni 23:28, 2 November 2007 (UTC)Reply

I'd suggest losing the "current time" part and leaving it as a static table showing the various US time zones (and pseudozones like Arizona) and their UTC offsets with and without DST.

Jordan Brown 09:17, 6 December 2006 (UTC)Reply

It needs to be either fixed or deleted. When I accessed the page today, the times weren't correct.

Maniacal Zebra 16:50, 28 October 2007 (UTC)Reply

Edit I just made edit

Would be too long to describe in the edit summary- I took out various "These people would most likely dislike/like DST because (time they get up) (whether the sun will have risen by then)" statements, and also cut out a bit saying DST in australia could change because a 13 y/o boy ahd emailed the PM-- unless he released a press onference saying eh was thinking about it because of that, it doesn't belong here. Did leave in that PM Howard requested different australian states please observe the same start/end dates for DST, but tinkered with the first two words for clarity. Cantras 16:32, 10 December 2006 (UTC)Reply

What's an "obs"? If you meant "observation", it needs to be spelled out in the text. I've changed it, but if you meant something else, you'll need to fix it. Thanks. - BillCJ 19:03, 10 December 2006 (UTC)Reply

Lengthy Australia text edit

I have deleted the expanded text on DST in Australia because of excessive length. The point of this page is to give a BRIEF summary on DST in the various articles. The entire text of that section has been placed on the the Talk:Time in Australia page, for inclusion in that article if that page's editors so desire. Thanks. - BillCJ 22:59, 11 December 2006 (UTC)Reply

I believe Lord Howe Island is unique - it is certainly unusual - in having a shift which is not one hour. That seems definitely worth a mention.
Are there any other inhabited parts of Australia which are too far from the main states to be ignored?
82.163.24.100 12:47, 6 April 2007 (UTC)Reply

USA from 2007 edit

Daylight saving time around the world#From 2007 says: "One potential issue is that some northern regions on the western edge of time zones will, for the first time since the 1974-75 "almost year round" DST experiment, have sunrise times that occur after 8am." If this means what I think, I don't think it's accurate. Here in northwest Ohio, for example, the sun rose at 8:01 on January 1, 2007, according to this site. —The preceding unsigned comment was added by 131.183.80.245 (talk) 19:09, 19 February 2007 (UTC).Reply

I agree, that statement is inaccurate. You don't need to be very far north to see sunrise after 8am druring the (non-DST) winter months. Also, with the new time changes, even mid-lattitude locations such as Indiana will see sunrise after 8am. 207.188.72.110 17:42, 9 March 2007 (UTC) JustInTimeReply

This section of the article also states: "Under Section 110 of the Energy Policy Act of 2005, the U.S. Department of Energy is required to study the impact of 2007's DST extension no later than nine months after the change took effect. Congress has retained the right to revert to the DST schedule set in 1986." The specific date by which the DOE Study was to have been completed was December 1, 2007 [Section 110(c) reads: "Report to Congress. -- Not later than 9 months after the effective date stated in subsection (b), the Secretary shall report to Congress on the impact of this section on energy consumption in the United States." The effective date stated in subsection (b) was March 1, 2007, and so nine months from that date is December 1, 2007.] I cannot find any information that the Secretary of Energy did report to Congress on December 1, and so I e-mailed DOE a week ago. However, there has been no response. Was an extension of the December 1 deadline granted? Thanks, Rodney Rodneysmall (talk) 20:56, 20 December 2007 (UTC)Reply

The section is weak on the number of weeks in DST. US DST is now always 34 weeks (minus an hour) long. Previously, it lasted for 29 or 30 weeks (-). See http://www.merlyn.demon.co.uk/uksumtim.htm. 82.163.24.100 (talk) 12:24, 3 November 2008 (UTC)Reply

Last Sunday in March edit

Is there a reason to create a link to this, instead of linking to Sunday and March? What could there be in such an article besides perhaps a list of last Sundays in March(s) past (not a very good use for a Wikipedia article I think) Schissel | Sound the Note! 20:33, 23 February 2007 (UTC)Reply

Colorado edit

but when then state Senator MaryAnne Tebedo attempted to present the idea to the state legislature, her research uncovered Federal laws forbidding the state-initiated extension of daylight saving time Who determines the borders of time zones? Is it the federal government, or state governments? If the latter, couldn't the same effect have been achieved by changing Colorado to Central time zone and simultaneously opting out from DST? Both would have the effect of making Colorado's time the same as Kansas' during summer and the same as Utah's during winter 65.27.11.162 03:14, 1 March 2007 (UTC)Reply

Neutrality edit

Whenever I try to fix the neutrality problem (I believe some parts are way too far in favour of Daylight Saving Time), somebody writes over it! I reverted a recent edit. Auroranorth 11:04, 3 March 2007 (UTC)Reply

I agree. People keep deleting my anti-DST messages. I just put one up about Halloween. Some people think late sunrise is bad, and we have a right to express our opinion. 70.239.25.200
Oddly enough, an edit which much more carefully described the opposition to the WA trial! I think this is not beyond resolution. Orderinchaos78 14:12, 3 March 2007 (UTC)Reply
Snarkiness is good! It helps. —The preceding unsigned comment was added by 74.225.130.13 (talk) 07:19, 4 March 2007 (UTC).Reply
I have rewritten the Australian section in an attempt to remove bias (either pro or con) and have removed the neutrality flag from the talk page. Eubulides 18:16, 28 March 2007 (UTC)Reply

GMT? edit

I don't see anywhere on this page whether or not GMT (Greenwich Mean Time) observes DST.

Greenwich is in the UK and as such does observe DST. This is the fundamental (and very important) difference between GMT and UTC. 207.188.72.110 16:47, 9 March 2007 (UTC) JustInTime (no-pun intended)Reply
GMT (according to the formal definition) does not observe DST, since it is defined as UTC, or the astronomically measured approximation of UTC. The UK actually observes something called BST (British Summer Time) in the summer. Often GMT is said to be the civil time in the UK, that is UTC in the winter and UTC+1 in the summer, but that is not correct. -- BIL 21:56, 9 March 2007 (UTC)Reply
This is similar elsewhere. In the US, Eastern Standard Time (USC-5) does not change, New York (et al.) simply jump to Eastern Daylight Time (UTC-4). samwaltz 16:05, 18 March 2007 (UTC)Reply
Actually as far as I'm aware it's more or less universal. Timezones don't change (Except perhaps when they are redefined), that would be unnecessarily confusing. Instead, DST is always a different timezone. A country or region changes the timezone it is observing if they use DST Nil Einne (talk) 07:54, 2 May 2008 (UTC)Reply
Notwithstanding the correct point that timezones don't change, it should be pointed out that 207.188.72.110 is effectively correct, according to Win32 and the .NET Framework at least: GMT observes DST and UTC does not. BIL is correct re the formal definition of GMT=UTC, of course. Mark Hurd (talk) 09:18, 24 November 2011 (UTC)Reply

Special Case for the Americas edit

Is there a good reason why the Americas had their own special bit at the top? I couldn't see one. I took it out - the links are still present in the main list. Bryson430 00:22, 11 March 2007 (UTC)Reply

Europe edit

It says : "All countries in Europe except Iceland observe DST and change on the same date and time, starting on the last Sunday in March and ending on the last Sunday in October." - NOT SO. All countries which are EU members[*] do so, together with the rest of continental Western Europe. But Russia in in Europe, and so are several fUSSR countries which I think follow Russian rules. Needs re-phrasing.

It says : "In the West European (UTC), Central European (CET, UTC+1), and East European (UTC+2) time zones the change is simultaneous:"

Not quite true, legally. Most countries change at 01:00 UTC, but I think UK law uses 01:00 GMT, differing by up to 0.9 seconds. However, UK time signals are UTC.

82.163.24.100 12:40, 6 April 2007 (UTC)Reply

The statement on Russia is unclear, unsourced, and as far as I can tell not true. Here's a reference: http://www.timeanddate.com/news/time/russia-dst-law.html — Preceding unsigned comment added by 213.196.255.94 (talk) 04:41, 6 October 2011 (UTC)Reply

Africa edit

I quote:


  • Canary Islands From last Sunday in March to Last Sunday in October and UTC.[1]
  • Egypt From last Friday in April to Last Thursday in September and UTC+3.
  • Namibia From first Sunday in September to First Sunday in April and UTC+2.
  • Tunisia From last Sunday in March to Last Sunday in October and UTC+2.

I have no idea what "I quote" is supposed to indicate; perhaps an artifact of a prior discussion. What I do observe is that Egypt isn't in the list. I saw a news article that said they abolished DST and Google says the current time is EET. However I'm not confident enough in that to actually make the edit. OldAndTired (talk) 13:10, 6 May 2012 (UTC)Reply

I have no idea what the "and UTC+x" means at the end of each bullet. If not explained, I'll get round to removing them in due course. -- SGBailey 15:01, 11 July 2007 (UTC)Reply

It is common practice when talking about timezones to use UTC+x. This means x hours after UTC.. so for example, South Africa is UTC+2. When it is midnight UTC, it will be 2:00am in South Africa. If it's 10pm UTC, it will be midnight in South Africa. --82.44.252.196 13:01, 28 October 2007 (UTC)Reply
Ditto the minus; Decatur, GA is UTC-5 OldAndTired (talk)

I think that I see what SGBailey is asking about. Maybe the problem is with the word 'and'.

Perhaps the quotes (from the Africa listings) would be clearer if the word 'and' was deleted, and replaced with the words 'when it observes'. —Preceding unsigned comment added by Boy.bowen (talkcontribs) 21:51, 21 January 2008 (UTC)Reply


If the article is correct that Morocco has discontinued its use of DST, then the map at the beginning of the article should be updated to reflect that. I don't have a way to edit the map myself, so I mention it here in the hope that someone else has the necessary access and knowhow. The map is an incredibly useful summary that, if maintained, all but obviates the rest of the article. —Preceding unsigned comment added by 169.252.4.21 (talk) 10:58, 25 March 2011 (UTC)Reply

"Obviates", gotta love it.

References

  1. ^ Although the Canary Islands politically belong to Spain, Europe, they are geographically in Africa. They have DST schedules according to EU rules.

History in the US edit

I'd like to see tabulated the rules and how they have changed over the years. I remember the early-1970’s energy crisis prompted an unusually long period of DST, and that a recent change moved it from the last Sunday of April to the first. I’ve seen a reference of that change in 1987 in Daylight_saving, but not the detail. Should the historical information go there instead? e.g.

YearsBeginEnd
2007-2nd Sunday in March1st Sunday in November
198?-20061st Sunday in AprilLast Sunday in October
197?-198?Last Sunday in April1st Sunday in November

John Rotunni 23:28, 2 November 2007 (UTC)Reply


Argentina edit

The argentinian government has recently decided to adopt DLS. There's information about it in newspapers in Englishand Spanish but I'm afraid it's not very detailed. --Max Sánchez (talk) 21:28, 25 December 2007 (UTC)Reply

Falkland Islands edit

The Falkland Islands sound too small a territory to have DST observed somewhere but not everywhere. I'm going to remove that comment if nobody can prove otherwise in a few days. HkCaGu (talk) 02:48, 9 March 2008 (UTC)Reply

Turkey may abolish daylight saving time edit

Turkey will abolish daylight saving time from 2009 onwards. Is there any confirmation to this? —Preceding unsigned comment added by 88.232.9.84 (talk) 21:37, 22 September 2008 (UTC)Reply

The change may now occur in 2011. 82.163.24.100 (talk) 12:16, 3 November 2008 (UTC)Reply

Since when is the United States part of Oceania? edit

I believe the United States is part of North America and should be shown somewhere close to Canada..... —Preceding unsigned comment added by 72.37.244.28 (talk) 20:08, 24 October 2008 (UTC)Reply

I made the same mistake. Look further down the outline, under North America.
How are the headings ordered, anyway? If it's supposed to be alphabetical, North America comes before Oceania and this should be a non-issue. --Jesdisciple (talk) 05:52, 27 October 2008 (UTC)Reply
I propose to merge the section on Hawaii and the U.S. territories in Oceania into the section on the section on North America. That way, there will be only one "United States" section. What is the consensus? Bwrs (talk) 14:11, 30 October 2008 (UTC)Reply
That sounds good to me... The only problem I see is the geographic (as opposed to political) aspect. Maybe that US section should remain under Oceania but only link to the mainland section where the old subsections are moved to? --Jesdisciple (talk) 16:18, 31 October 2008 (UTC)Reply

US & Territories edit

Right now, Puerto Rico and the Virgin Islands are missing. Should we really separate mentioning the U.S. in different continents or have them combined in one place. After all, they're all under the same law (with different applications). HkCaGu (talk) 01:29, 7 November 2008 (UTC)Reply

What is the point of the "Other U.S. locations" section??? edit

The "Other U.S. locations" section merely says "See U.S. in Oceania" where the phrase "U.S. in Oceania" is a link that goes nowhere (i.e., remains at the same place on the same page).

In fact, it is completely unclear which "other U.S. locations" are being referred to. It appears that it means ones other than those having their own section headings. But No! -- that is not what it means.

Most if not all parts of the U.S. in North America that don't have their own section heading are covered by the section "From 2007 on".

Probably the organization ought to be changed. Under "From 2007 on" there should be a first subsection "Most of the U.S. that contains what the current section "From 2007 on" contains now. The other parts of the U.S. with their own sections (Alaska, Arizona, Colorado, etc.) should also be subsections of (the proposed) "From 2007 on", coming after the "Most of the U.S." subsection.Daqu (talk) 06:42, 2 March 2009 (UTC)Reply

Hawaiian mystery edit

The citation for the claim that Hawaii briefly went on DST in 1933 was a little dubious to me. The page referenced seemed . . . less than academic to me, because the author claimed that he had not personally read the source. Which means that our article is quoting hearsay. There are others who claim that the length of time Hawaii was on DST was one day — for example, see how this Linux coding group made a special rule for the one day of April 30-May 1 1933 in their database of all DST rules — but they don't have anything terribly reliable to back them up either. I've reached a kind of dead end on the internet, myself, but it seems to be leading to a solid (if obscure) source. Apparently in the Journal of the House of Representatives of the Seventeenth Legislature of the Territory of Hawaii, on page 1662, there is record of an "Act amending Sections 2132 and 2133 of the Revised Laws of Hawaii 1925 to repeal Act 90 of the Session Laws of 1933". This Act is about daylight savings time, but I don't know what it says. All I have is a breadcrumb, but it seems a tasty one. If anyone could find that volume, they'd likely have something better than "this guy who had heard what some other people said about a book I didn't read". It might not be able to tell why the experiment with DST started or stopped, but it would at least reliably verify that it happened, which is more than The American Atlas (the source cited by the reference currently given) might be able to do.

I also know that the date of this legislative action happened somewhere between February 15th and 17th, 1933. A microfilm search of back editions of the Honolulu Star-Bulletin and/or Advertiser for those dates might throw some light onto the question of why Hawaii took this brief trip down DST lane. CzechOut | 22:44, 8 March 2009 (UTC)Reply

Antarctica? edit

What's the usage in Antarctica? 68.63.137.117 (talk) 21:25, 18 September 2009 (UTC)Reply

It depends on the country controlling each station on the continent as well as the location of the station. For a current time zone map, please see http://www.worldtimezone.com/time-antarctica24.php. --Glenn L (talk) 04:06, 19 September 2009 (UTC)Reply

West Indies edit

Back a few years ago in approx 2002 or 2003 the Dominican Republic (during the time of Pres. Hipolito Mejia) tried to implement Daylight Savings time, but did it backwards i.e. they started in the summer on standard time, and then put the clocks backwards in the winter, as an "un-daylight-savings" time. The whole thing didn't turn out well, and they abandoned it a little while later. While it is (obviously) in living memory, does anyone have access to any documentation on this, otherwise, without a citation, it wouldn't be worth putting on the main article?

It was said that the Republic of Ireland did the same in 1968 or 1971, by following the UK (which omitted Winter Time 1968-71) but expressing it differently. Ask an Irish lawyer. 94.30.84.71 (talk) 22:04, 17 January 2011 (UTC)Reply

Changeover dates edit

I've always wondered why the changeover dates are not symmetrical about the Winter Solstice. For example, in most of Europe, summer time ends at the end of October, roughly two months before 21 December (the shortest day) but it then begins at the end of March, three months after 21 December. Why not define the start and end dates to be the same number of weeks either side of the solstice - eg end of October and end of February, or end of September and end of March? I wonder if the reason for this difference needs to be explained in the article - if anyone knows what the reason is! Bardenite (talk) 12:23, 23 October 2009 (UTC)Reply

From the look of the article it seems Europe adopted the British dates which in turn now roughly correspond to the end of the school spring term and the autumn half-term, but I don't know if that was the case or the reasoning when they were adopted - [1] & [2] shows the dates at both end jumped around a bit. Some of the difference is almost certainly down to administrative convenience and I think the sun rises and sunsets themselves are not quite symmetrical. Timrollpickering (talk) 23:49, 27 June 2010 (UTC)Reply

The TZ Variable edit

The handling of the dates of Summer Time with the TZ variable of UNIX has four cases :

  1. No Summer Time
  2. Summer Time matches a long-term M-type rule
  3. Summer Time matches a long-term J-type rule
  4. Summer Time matches neither long-term

I think that it would be useful to say that many places are case 1, many places are case 2, no places are now case 3; and Israel and Iran are (differently) case 4, for which an M or J rule changed annually can be used.

But check the facts first. 94.30.84.71 (talk) 22:13, 17 January 2011 (UTC)Reply

South Africa edit

The map is wrong in suggesting that South Africa (and Botswana) once had DST.

South Africa has never used this ridiculous system. Please do not ask me to produce evidence of this. The onus must be on the people who claim SA ever used this ridiculous system to show any evidence of this even more ridiculous claim.

Paulalexdij (talk) 13:07, 22 February 2011 (UTC)Reply

It was used for two years 1942-43 and 1943-44. See Doris Chase Doane, Time-Changes in the World, Hollywood, Professional Astrologers Inc., 1971, p.97. Eclecticology (talk) 02:45, 2 March 2011 (UTC)Reply

Well I am very surprised and I stand correctedPaulalexdij (talk) 07:07, 3 July 2012 (UTC)Reply

Time conversions edit

I'm looking for a web page where I can easily and reliably find out what time it's going to be in another city overseas. I live in New York City, which is currently 5 hours behind "zulu time" in Greenwich. My friends in Tokyo and Seoul are currently 14 hours ahead of me.

It would be nice to have a page that reminds me that East Asia is 14 hours ahead, does the hour and date arithmetic -- and -- reminds me that starting next week, my friends there will be "only" 13 hours ahead.

Problems with current pages:

  • Phrases like "No DST applied" are ambiguous. I'd rather be told that the country does not observe daylight savings (or for you limeys, "summer time" ;-)
  • If I'm planning an international phone call, I don't just want to know the current time zone difference: I need to know how DST rules will affect this difference, especially when my region and my friend's region start "daylight savings" (USA) or "summer time" (Europe) by different rules. What if we're planning a series of teleconferences?

I'd prefer for all this to be done here at Wikipedia, if User:Tim Starling is still around to write the PHP code. Or if we can user parser functions or something. --Uncle Ed (talk) 19:07, 10 March 2011 (UTC)Reply

A tailor made site like http://timeanddate.com/ is probably superior, because it can write the current time in any country directly. Maybe it is enough that a Wikipedia article write the DST offset, summer and winter per country. We have List of time zones by country, but it does not show DST. List of time zones by UTC offset shows only a mark, "*" or "**" for daylight saving time, maybe hard to interpret, and more hard to find the country. Daylight saving time around the world does not give fast DST details, and does not write the time zone. --BIL (talk) 19:59, 10 March 2011 (UTC)Reply

Health effects of Spring circadian rhythm disruption edit

Health effects of Spring circadian rhythm disruption

The enforced sleep deprivation and circadian rhythm disruption of the Spring time change has a number of adverse health effects.[1] PMID 11152980. The body's circadian rhythm does not readily adjust to the effects of the Spring change; instead, the body continues to slowly adjust to the earlier morning sunlight. PMID 17964164. The circadian rhythm does more readily adjust to the Fall change, which allows an hour of extra sleep PMID 17964164; for instance; an actual reduction of traffic fatalities has been seen following the Fall change. PMID 7832269. Because the Spring change imposes a number of ill health effects,[2] the nation of Kazakhstan discontinued the use of Daylight saving time.[3]


Given the dissaprate effects, it is difficult to understand why there is no delay in the Spring change. The clocks change at about the spring equinox in Europe and the United States, but well over a month after the autumnal equinox.

The opposite would make sense for purposes of health. The body's circadian rhythm readily adjusts to the Fall change, which allows more sleep, but adjusts with great difficulty and slowness to the Spring change, which effective deprives an hour of sleep (measured at just over 60 minutes in one study) and requires rising earlier. After the change, people continued to rise earlier on the weekends in a pattern precisely tuned to the gradually earlier rising of the sun. For health reasons, the Spring change should be delayed for at some weeks after the Spring equinox, to allow the body has the chance to adjust based on sunlight. Possibly a part of the reason that the body adjusts so easily is the Fall is simply that the natural light progression has already occurred in the month following the equinox. See notes in the next discussion section, below, on Health effects of circadian rhythm disruption.


Curr Biol. 2007 Nov 20;17(22):1996-2000. Epub 2007 Oct 25. The human circadian clock's seasonal adjustment is disrupted by daylight saving time.

Kantermann T, Juda M, Merrow M, Roenneberg T.

Ludwig-Maximilian-University, Goethestrasse 31, D-80336 Munich, Germany. Abstract

A quarter of the world's population is subjected to a 1 hr time change twice a year (daylight saving time, DST). This reflects a change in social clocks, not environmental ones (e.g., dawn). The impact of DST is poorly understood. Circadian clocks use daylight to synchronize (entrain) to the organism's environment. Entrainment is so exact that humans adjust to the east-west progression of dawn within a given time zone. In a large survey (n = 55,000), we show that the timing of sleep on free days follows the seasonal progression of dawn under standard time, but not under DST. In a second study, we analyzed the timing of sleep and activity for 8 weeks around each DST transition in 50 subjects who were chronotyped (analyzed for their individual phase of entrainment). Both parameters readily adjust to the release from DST in autumn but the timing of activity does not adjust to the DST imposition in spring, especially in late chronotypes. Our data indicate that the human circadian system does not adjust to DST and that its seasonal adaptation to the changing photoperiods is disrupted by the introduction of summer time. This disruption may extend to other aspects of seasonal biology in humans.

PMID 17964164


Am J Public Health. 1995 Jan;85(1):92-5. Daylight saving time and motor vehicle crashes: the reduction in pedestrian and vehicle occupant fatalities.

Ferguson SA, Preusser DF, Lund AK, Zador PL, Ulmer RG.

Insurance Institute for Highway Safety, Arlington, Va 22201. Abstract

Fatal crashes were tabulated for 6-hour periods around sunrise and sunset, from 13 weeks before the fall change to standard time until 9 weeks after the spring change to daylight saving time. Fatal-crash occurrence was related to changes in daylight, whether these changes occurred abruptly with the fall and spring time changes or gradually with the changing seasons of the year. During daylight saving time, which shifts an hour of daylight to the busier evening traffic hours, there were fewer fatal crashes. An estimated 901 fewer fatal crashes (727 involving pedestrians, 174 involving vehicle occupants) might have occurred if daylight saving time had been retained year-round from 1987 through 1991.

PMID 7832269 [PubMed - indexed for MEDLINE] PMC 1615292Free PMC Article

Sleep Med. 2001 Jan;2(1):31-36. Fatal accidents following changes in daylight savings time: the American experience.

Varughese J, Allen RP.

Department of Symbolic Systems, School of Humanities and Sciences, Stanford University, CA, Stanford, USA Abstract

Objective: This study examines specific hypotheses that both sleep loss and behavioral changes occurring with the time shifts for Daylight Savings Time (DST) significantly effect the number of fatal traffic accidents in the United States of America.Background: It has been reported that there is a significant increase in the number of automobile accidents in the spring shift to DST due to the loss of 1 h of sleep. But the extra hour gained at night with the shift from DST in the fall has been variably reported to be associated with increases and decreases in the number of automobile accidents which may reflect either behavioral anticipation with an extended late night prior to the change or the benefit of extra sleep after the change.Methods: Data from 21 years of United States' fatal automobile accidents were gathered. The mean number of accidents on the days at the time of the shifts (Saturday, Sunday and Monday) was compared to the average of the corresponding mean number of accidents on the matching day of the weeks preceding and following the shift. This was repeated for each DST shift. The number of accidents for a particular shift was also correlated with the year of the accidents.Results: There was a significant increase in accidents for the Monday immediately following the spring shift to DST (t=1.92, P=0.034). There was also a significant increase in number of accidents on the Sunday of the fall shift from DST (P<0.002). No significant changes were observed for the other days. A significant negative correlation with the year was found between the number of accidents on the Saturdays and Sundays but not Mondays.Conclusions: The sleep deprivation on the Monday following shift to DST in the spring results in a small increase in fatal accidents. The behavioral adaptation anticipating the longer day on Sunday of the shift from DST in the fall leads to an increased number of accidents suggesting an increase in late night (early Sunday morning) driving when traffic related fatalities are high possibly related to alcohol consumption and driving while sleepy. Public health educators should probably consider issuing warnings both about the effects of sleep loss in the spring shift and possible behaviors such as staying out later, particularly when consuming alcohol in the fall shift. Sleep clinicians should be aware that health consequences from forced changes in the circadian patterns resulting from DST come not only from physiological adjustments but also from behavioral responses to forced circadian changes.

PMID 11152980 — Preceding unsigned comment added by Ocdncntx (talkcontribs) 19:49, 13 March 2011 (UTC)Reply

Table - start and end dates edit

What do the S and N signify ? South and North ? If so, Cuba is wrong for one. -- Beardo (talk) 01:26, 30 October 2011 (UTC)Reply

Table is thoroughly confusing and unhelpful edit

I am a longtime Wikipedia editor, but I came to this article in the capacity of an ordinary end-user, trying to find information about daylight saving time in the United States and Spain. But the table tells me nothing I want to know. What the hell is EU-Rule and why is it not wikilinked or explained anywhere in this article? Likewise, what the hell do "N:" and "S:" stand for? North and South? What does US-Rule stand for? Is that supposed to mean that I consult the United States row of the table for information? Why is there no Europe row? I see that TZ master (talk · contribs) has made a multitude of edits to this page, overhauling it completely, well thanks, it is useless now! Elizium23 (talk) 20:37, 30 October 2011 (UTC)Reply

I have restored the last revision before TZ master's edits so that new changes to the article can be discussed here before they are implemented and seen by the public. Elizium23 (talk) 00:43, 31 October 2011 (UTC)Reply
Perhaps the table can be a separate page, but this page should stay as it is. -- Beardo (talk) 20:18, 13 November 2011 (UTC)Reply

Cuba's Sentences make no sense edit

"Cuba normally observes DST from March to October although the precise dates vary. Thus for two years, Cuba stayed on DST throughout the year."

The "Thus" implies that you can connect the facts in the previous sentence to the conclusion in the second... but there's no logical connection between the two. I don't know enough of the facts to figure out what this is SUPPOSED to say, but maybe someone else does? — Preceding unsigned comment added by Dballing (talkcontribs) 16:22, 4 November 2011 (UTC)Reply

I suspect the thus is supposed to connect to the varying - i.e. Cuba stayed on summer time for 30 months. -- Beardo (talk) 20:16, 13 November 2011 (UTC)Reply

Sort order edit

Any particular reason for having the countries and regions that do not observe DST listed first? A quick glance at the map shows that North America and Europe are the chief user of daylight saving time. There are also some Southern Hemisphere countries.

If no one objects, I'm planning to put North America and Europe first, followed by South America. --Uncle Ed (talk) 00:47, 28 February 2012 (UTC)Reply

Africa edit

Neither Canary Islands, Cueta or Melilla belong to the African continent. They are, in fact, regions of Spain and belong to the European continent. — Preceding unsigned comment added by 217.111.219.238 (talk) 14:25, 22 March 2012 (UTC)Reply

Angola edit

I happened to notice that the map says Angola uses DST, but the table says it does not and never has. A quick check at dateandtime.com confirms that Angola does not currently use DST, so the map is certainly wrong, and the table may be right. I was unable to find out whether it ever has. Perhaps someone more expert than me can give it some attention. — Preceding unsigned comment added by 87.194.87.186 (talk) 17:53, 29 July 2012 (UTC)Reply

Daylight saving time by country redundancy edit

Isn't it a bit redundant to have both Daylight saving time by country and Daylight saving time by region and country? I get that one is supposed to be more concise, but on top of the general Daylight saving time in Country X and Daylight saving time in Continent Y AND the timezone specific articles I think we are getting too much redundancy and maintenance overload. I'm fine with the country level and continent level articles (although a case could be made that even the continent level is redundant if we have a global overview). But surely we only need one global overview article which can then link to the country and continent level articles as need be?Peregrine981 (talk) 08:25, 16 October 2012 (UTC)Reply

If no one objects soon I will merge the two articles. Peregrine981 (talk) 18:25, 20 October 2012 (UTC)Reply

Armenia edit

The table here shows Armenia as being in Europe. The article Europe draws the line north of Armenia, including only part of Georgia in Europe, so that even the northern border of Armenia is not at the dividing line.

I suggest that we either change the table to read "Asia", or, perhaps, change Armenia, Georgia, and perhaps others to read "Eurasia". . . Jim - Jameslwoodward (talk to mecontribs) 14:24, 1 March 2014 (UTC)Reply

Align with page about timezones? edit

I've been trying to extract complete timezone information from this page (for DST) in combination with the article on timezones by country https://en.wikipedia.org/wiki/List_of_time_zones_by_country

However, it is slow going. One difficulty is that different names are being used for territories. For example the timezones by country page uses "Macau (China)" and this page uses "Macau (CH)".

On the timezones by country page there is one row for country, and the different parts of the country are in one column separated by a newline. On this page every "part" of a country has it's own row (with the abbreviation of the "main country" in brackets after the name). Also I think sometimes completely different territories are being referenced.

Just wondering if some effort to align these two pages would be welcome?

For computing purposes of course it would be ideal to combine the information from both pages into one table, but then I guess it would be to wide for the Wikipedia layout? — Preceding unsigned comment added by Iion tichy (talkcontribs) 12:15, 17 February 2015 (UTC)Reply

Oceania edit

Is Oceania the continent that Australia is located? I grew up learning that continent 'Australia', so I get confused often. Sorry if this seems more like a YouTube comment, I haven't used this section of Wikipedia in a while. Jay M (talk) 22:58, 16 March 2015 (UTC)Reply

Nagarno-Kharapagh edit

Why is Nagarno-Kharapagh placed on the same line as Azerbaijan? This land has been transferred to Azerbaijan by the USSR which is something that Armenians protested. It was under the control of Azerbaijan until war started by the Armenian population to free itself. The land is no longer under azeri control and has no ties to its government. Nagarno-Kharapagh or its historical name of Arztakh should have its own line. Vmelkon (talk) 17:03, 17 March 2015 (UTC)Reply

Discuss this at Talk:Nagorno-Karabakh Republic. This article is Daylight saving time by country. We can not have discussions about the political situation of Nagorno-Karabakh in this article and every other article where the area is mentioned. Because people who edit this article are probably knowledgeable about daylight savings time but not about the political debate in Nagorno-Karabakh, and because too much effort is spent on Wikipedia talk pages in discussing controversial matters in many talk pages in parallel. --BIL (talk) 21:08, 17 March 2015 (UTC)Reply

Caribbean edit

Seeking among countries in Central America found that many of the Caribbean countries are listed here in this section. I have found a page containing this Caribbean countries.

I propose to regroup the Continent, although is not continent but region, for this countries to Caribbean and rename the Continent table header to Region. --Cancuen (talk) 07:39, 2 September 2015 (UTC)Reply

Great Britain still lists GMT edit

The entry for Great Britain still lists its times as offsets from GMT, instead of UTC. The Wikipedia page about GMT however lists that the 'GMT' notation is deprecated, and that UTC is used instead.

Is the current version still accurate or should it be updated? — Preceding unsigned comment added by 213.17.125.205 (talk) 18:47, 13 March 2017 (UTC)Reply