Talk:Daylight saving time

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[edit] Changes to lead and to "Energy use"

These changes introduced several problems.

  • The revised lead suggests that DST applies only if clocks are changed for part of the year. But as the body of the article makes clear, some areas, such as Iceland, observe DST all year.
  • The revised lead unnecessarily repeats the notions that DST saves energy and promotes public health and safety. These ideas are already featured prominently in the lead; they should not be mentioned twice.
  • The change removes from "Energy use" the claim that DST may increase gasoline consumption, which is supported by an article by Shawn McCarthy in the Globe and Mail. No reason was given for this removal.

I therefore undid the change as part of a recent cleanup, which also improved the recently-introduced discussion of "daylight losing time". Eubulides (talk) 05:11, 7 January 2008 (UTC)

Response: It seems attempts to revise the unscientific, poorly written descriptions of DST are not allowed.

  • DST does not increase or decrease daylight at any time. The amount of daylight is determined by the seasonal inclination of the earth to the sun.
    • That is covered under Daylight saving time #Benefits and drawbacks, which says "Obviously it does not change the length of the day; the longer days nearer the summer solstice in high latitudes merely offer more room to shift apparent daylight from morning to evening so that early morning daylight is not wasted." This is briefly summarized in the lead, which says "afternoons have more daylight and mornings have less". Eubulides (talk) 17:39, 7 January 2008 (UTC)
  • The lead does not suggest a reason for DST, historically or in current use. There is no mention of its primary goal in saving energy.
    • No, the lead says that DST benefits retailing and sports and reduces traffic fatalities, and that an early goal was to reduce energy usage. Eubulides (talk) 17:39, 7 January 2008 (UTC)
  • The history of DST should be separate from the opening paragraph.
    • When the article went through review as part of becoming a featured article, earlier reviewers objected to having lots of short, choppy paragraphs, and suggested a maximum of 3 paragraphs in the lead. Eubulides (talk) 17:39, 7 January 2008 (UTC)
  • The article should eliminate conjecture and unscientific claims masquerading as research. Articles in the paper are not research. Statistics about gasoline consumption or peak energy demands in Australia that do not take into account other variables are just anecdotal.
    • If there is sound scientific evidence about a subject, of course that should take precedence. The paper concerning energy demands in Australia is among the soundest of the citations mentioned; if we can't cite sources like that, we might as well not have a Wikipedia article at all. The gasoline-consumption article is not as good, but is the best source we have on the subject of gasoline consumption; better sources would of course be welcomed, but in the mean time gasoline consumption is a valid issue and we should use the best source we have. Eubulides (talk) 17:39, 7 January 2008 (UTC)

Bryan00009 (talk) 12:27, 7 January 2008 (UTC)

[edit] UK-US diagram is unreadable

This change introduced a gallery containing Image:Timediffrence_uk-us.png. Unfortunately, the image is unreadable, so I am reverting the change for now. I do like the idea of showing a diagram of time differences. I suggest two things. First, the image needs to be modified so that it is at least somewhat readable as a thumbnail; see the existing maps and diagrams on the page for illustrations of this. Second, please use the UK and Chile instead, as that is a more interesting example. Daylight saving time #Observance practices already says "The time difference between the United Kingdom and mainland Chile may therefore be three, four, or five hours, depending on the time of year" and the image could be an illustration of this point. Eubulides (talk) 16:55, 15 January 2008 (UTC)

Thanks for this improvement; the new image is much more readable. I made this further change to put the new image next to the text that it illustrates, and to adopt the style for images that is used elsewhere on the page. I have some further suggestions to help improve it even more:
  • The image incorrectly states that Western Australia ends DST at 01:00 on March 29. It actually ends at 03:00 local time on March 30. See the Western Australia Daylight Saving Bill (No. 2) 2006 (PDF). As an aside, doesn't daylight-savings-time.info use Zoneinfo code? That should help it avoid bugs like this.
  • Once this bug is fixed, the diagram will indicate that the seven-hour offset between Western Australia and Germany exists for only seven hours of real time, from 2008-03-29 18:00 to 2008-03-30 01:00 UTC, which means that it's not that good an example: it makes it appear that the seven-hour offset lasts only for a short time and can be safely ignored for many applications. Better would be to pick two locations where the unusual offset lasts longer.
  • Western Australia is trialing daylight-saving; it is controversial there and may well not become permanent. It would be better to use a more-stable location, where daylight-saving is well established and not likely to change.
  • With the above two points in mind, I suggest comparing New York City to São Paulo; the resulting diagram has several weeks of the intermediate two-hour offset. However, that diagram incorrectly claims that DST ends in São Paulo at 2008-02-17 23:00 local time; the correct ending time is 2008-02-17 00:00 local time (equivalent to 2008-02-16 24:00).
  • The big "March 08" and "Apr 08" in the diagram are inconsistent about whether a month abbreviation is used, and the "08" is a bit too informal here. Better would be "March 2008" and "April 2008", or perhaps just "March" and "April" with the 2008 in the caption. But, come to think of it; there's another problem: the image uses English words, and thus is less useful for translations such as the Spanish DST article. So perhaps "2008-03" and "2008-04" would be better labels. Similarly, the rest of the diagram should avoid English-specific wording as much as possible.
  • The URL to "www.daylight-savings-time.info" grates a bit, because it says "savings" rather than the normative "saving". But when I use "www.daylight-saving-time.info" (without the "s"), the web server immediately rewrites it to use the "s". Can that be fixed on the web server side? I'd rather use URLs without the "s" and have it stay that way on my screen.
  • The diagram is graphed as if clocks changed at midnight, but they actually change at a particular UTC time, which is not exactly midnight. I suggest altering the graph so that the transitions are graphed accurately according to the UTC time, not just the local date.
Again, thanks for the diagram: I'm not trying to be ungrateful! I'm just trying to help make it better. Eubulides (talk) 21:00, 15 January 2008 (UTC)

OK, I'll take another look and be back with changes as soon as I can. About writing the change in hour in UTC time - I disagree, I think it makes more sense to put in under local time. And western Australia ends DST at 2:00, or I'm dyslectic (which is an option, but please recheck). -mouse_on_march —Preceding unsigned comment added by 217.132.226.190 (talk) 09:45, 17 January 2008 (UTC)

I see your point about displaying the time in UTC, but could you at least graph the time in UTC? Otherwise, the graph won't be accurate, since it will show different transitions in different time zones as if they were in the same time zone. As for the Western Australian time, the legislation clearly says that by "the hour of 2 a.m." it means the "hour as determined by standard time". This is 3 a.m. local time in the autumn transition. Remind me again why your website is not using Zoneinfo? It's very good and quite accurate. Eubulides (talk) 15:52, 17 January 2008 (UTC)

I'm uploading the graph again, fixed based on most of your suggestions. The website is not using zoneinfo becuase zoneinfo is sorted by continents, and the time zone regions are not optimized for the convenience of the ignorant user. I'm using several sorces, including zoneinfo. All the bugs should be fixed by the end of the week. —Preceding unsigned comment added by 89.138.13.25 (talk) 13:07, 26 January 2008 (UTC)

Thanks! The diagram is much appreciated. Eubulides (talk) 17:23, 26 January 2008 (UTC)

[edit] "So-called" drive-ins?

"DST also hurts prime-time broadcast ratings and theaters, especially outdoor cinema, so-called drive-ins."

Why "so-called"? The sentence implies that "outdoor cinema" is the preferred term, but there is no page with that title, and that term is not mentioned on the page for Drive-in theater. (I see that page has a neutrality tag, for some reason that's not obvious to me.)

[edit] India

The map shows India as one of the countries which "no longer use DST". Are you guys sure about this? I live in India and have never heard of such a practice being used from my parents or grandparents or anyone else. They don't even know about it. ReluctantPhilosopher (talk) 16:05, 9 March 2008 (UTC)

Time in India says they did. Also, the tz database says DST was used there during World War II. Eubulides (talk) 17:50, 9 March 2008 (UTC)

[edit] What readers most need from WP is when and which way to reset our clocks

The most useful information to most consulting this reference seems to be missing. On which dates, and exactly how (which way), are we supposed to reset our clocks? --by 66.167.164.17 at 16:30, 16 March 2008 (UTC)

There's no simple answer to that question; it depends on where you live. Please see Daylight saving time around the world for some (but alas, not all) of the details. This page is referred to in the lead section of Daylight saving time. Eubulides (talk) 23:44, 16 March 2008 (UTC)
I suggest we put one up as an example for 2 different countries, when they changed their time at different times, to make people see the practical value of the article early. 79.103.188.125 (talk) 15:14, 17 March 2008 (UTC)
Thre is such an example in Image:Time-differences-brz-us.png but this is a fairly specialized topic and would be out of place in the lead (that image is currently used in Daylight saving time #Observance practices). To try to address this problem, I inserted a hatnote to point readers more directly at Daylight saving time around the world; hope this helps. There used to be a similar hatnote there long ago; perhaps it was better that way. Eubulides (talk) 16:38, 17 March 2008 (UTC)
Maybe we should start a separate article just like airline destination lists are separate from airlines. HkCaGu (talk) 17:07, 17 March 2008 (UTC)

[edit] Table for US/Canada/Europe 2008/2009

I have added a box with transition dates for US/Candada and for Europe, for 2008 and 2009. It might be reverted, since some encyclopedia people want to have general rules and mathematical formulas, not tables containing limited info. If it is useful is less interesting to them. Most people who have DST live in US/Canada or Europe. --BIL (talk) 07:03, 18 April 2008 (UTC)
Yes, that table is not encyclopedic. First Wikipedia is not a directory. Second, the table is limited to just a few places and a few years. Third, the table is incorrect, as not all of US/Canada observes DST, and some Europeans use different rules than what is in the table. I don't know offhand how to address these objections, so I removed the table. Eubulides (talk) 07:22, 18 April 2008 (UTC)
>>some Europeans use different rules<<
Not true (unless you are referring to the 300,000 or so Icelanders, who do not observe DST at all)! Clocks go forward/back on the same dates in all European countries: see European Summer Time. -- Picapica (talk) 16:20, 18 April 2008 (UTC)
I was thinking about the Russians and Belarusians, who switch the same dates but at different times from the EU. The Icelanders are also an exception. This sort of thing can't easily be captured in a small table. Plus, the table would discriminate against those in Argentina, Australia, Mexico, Namibia, and you get the idea. There are just too many details here.
What I would prefer would be for the "Date and time" tab in Special:Preferences ask users to specify their Zoneinfo entry, and then let the Wikipedia software tell each reader what the rules are for their location. That would be fine. But putting the complete table in Daylight saving time is way overkill, and a partial table is unencyclopedic. Eubulides (talk) 16:50, 18 April 2008 (UTC)

[edit] Premature archive?

Was this discussion archived to hide the many flaws of this article? How this strange article could ever have been a featured article boggles the mind. It should perhaps rather have been called Speculation on the supposed controversies regarding Daylight Saving Time... —Preceding unsigned comment added by 198.54.202.74 (talk) 21:29, 29 April 2008 (UTC)

You're talking about the discussion from 2007 and earlier? I archived it back in January because Dec. 31 was on a year boundary and the talk page was getting a bit long (33 topics in the ToC). Anyway, archives don't hide anything; all the material is still there. Are there any specific problems that you have in mind? Eubulides (talk) 22:22, 29 April 2008 (UTC)
The comment above should be clear enough - I am talking about your (Eubulides) strong personal bias against DST. The article history shows that you revert or otherwise change anything that goes against your basic opposition to DST. The issues raised there have not been resolved. My impression is that most people just gave up as you seem to be unwilling to let the community work towards any sort of improvements. 198.54.202.74 (talk) 06:03, 30 April 2008 (UTC)
That's still a bit vague. Could you please give details, preferably with a specific proposal for improved wording? I just now looked at that archive and found Talk:Daylight saving time/Archive 4 #NPOV, which contains a strongly worded (albeit similarly vague) complaint that the article is biased in favor of DST, along with Talk:Daylight saving time/Archive 4 #Extreme anti-DST bigotry in this article, a much longer section with concrete proposals, which resulted in some improvements to the article. I didn't see any obviously unfinished work there, but quite possibly I'm missing something. Eubulides (talk) 07:13, 30 April 2008 (UTC)

[edit] Reference 65 no longer availible

65. ^ Ann Parker. "Sundials put old slant on telling time", Santa Cruz Sentinel, 2007-03-11. Retrieved on 2008-03-08.

I could not find the article - can someone else update the link? —Preceding unsigned comment added by Arcking (talk • contribs) 22:03, 4 May 2008 (UTC)

Thanks for mentioning the problem. The Santa Cruz Sentinel is fairly bad at keeping their old stuff online, and this isn't the first time that link stopped working. I looked for where they moved it to, and failed. Instead of trying to track that article, which wasn't that great a source anyway, I replaced the citation with a citation to Waugh 1973, a higher-quality source although one that is (alas) not freely available online. Eubulides (talk) 01:33, 5 May 2008 (UTC)

[edit] Energy Savings

Does anyone have a lead on where to find the report commissioned by Congress on the energy savings effects of extending DST? Mrshaba (talk) 21:38, 30 May 2008 (UTC)

As far as I know it is not available. If anyone can turn it up please let us know here. Eubulides (talk) 01:16, 31 May 2008 (UTC)