Daylight Saving Time In The US

[swbrotha100]

Well Daylight Saving Time (DST) starts at 2:00 am local time on Sunday, March 10. Most of the country will spring forward an hour. There are certain areas that don't observe it (Hawaii, most of Arizona, various US territories). Some of you love it, some of you hate it, most probably don't pay attention except for twice a year. Any thoughts or opinions?

Somewhat related, are there a lot of signs out there marking time zone boundaries? I have seen them marked at the Hoover Dam, and I see Nevada has a sign on northbound US 93 just after the Hoover Dam Bypass bridge. There weren't any signs I could remember between Bullhead City AZ and Laughlin NV.

[Alex]

If it weren't for DST, we'd not have a 6 pm sunset until March 22nd... Always find it a plus as it allows for more photography later in the day when on the road as well.

[KEVIN_224]

I love Daylight Saving Time...but wish it were still done on the first Sunday of April, not this early. Also...why isn't Indianapolis in the CENTRAL time zone? Their longitude is nearly identical to that of Nashville, which is obviously in the central time zone.

[corco]

I wish the country would go onto daylight savings time all year. Two years of living in Arizona made me realize the shift is more annoying than anything else, but I do prefer a later sunrise and sunset, so stick with daylight savings time. I guess one of the old arguments against DST year round is that kids can't stand out at the bus stop in the dark, but for better or worse the whole notion of kids standing out at bus stops unattended is going away anyway, so may as well just go to DST year round.

Somewhat related, are there a lot of signs out there marking time zone boundaries? I have seen them marked at the Hoover Dam, and I see Nevada has a sign on northbound US 93 just after the Hoover Dam Bypass bridge. There weren't any signs I could remember between Bullhead City AZ and Laughlin NV.

There's signs most places I've seen. Arizona is dicey though- there's no "we don't observe daylight savings time" signs going into Arizona from Utah or New Mexico (or "daylight savings time observed" the other direction), so part of the year that's confusing.

I don't think there is a sign at Bullhead/Laughlin though, going through my pictures, but I'd say that's the exception rather than the norm for most of the country.  Actually, I don't think there are any time zone signs as you enter Arizona from any state. There are "entering Pacific time" as you cross into California, but nothing as you enter Arizona.

[J N Winkler]

Well Daylight Saving Time (DST) starts at 2:00 am local time on Sunday, March 10. Most of the country will spring forward an hour. There are certain areas that don't observe it (Hawaii, most of Arizona, various US territories). Some of you love it, some of you hate it, most probably don't pay attention except for twice a year. Any thoughts or opinions?

Like others who have commented on this thread, I would actually prefer DST year-round, not standard time year-round or some other variation like DST in winter and double-DST in summer.  The change is a nuisance, but I deal with it by simply not changing the time on unimportant clocks in the autumn and mentally preparing myself to lose an hour of free time the evening the clocks move forward in spring.

The contexts in which DST time changes cause me maximum inconvenience are all IT-related.  Older versions of robocopy fail (this particular issue wasn't fixed until the /DST switch was introduced in Windows 7's version of robocopy).  I also have wget wrapper scripts which rely on timestamp parsing to determine whether files found on a given server have been uploaded since that server was last checked.  To save coding effort, I hard-coded the timezone offsets, and during DST changes this causes me problems since my computer is set to British time and now neither of the annual time changes are synchronized between the US and the EU.  (Before the US and Canada lengthened DST, one of the changes occurred at the same time on both sides of the Atlantic--I can't remember whether it was spring or autumn.)

Somewhat related, are there a lot of signs out there marking time zone boundaries? I have seen them marked at the Hoover Dam, and I see Nevada has a sign on northbound US 93 just after the Hoover Dam Bypass bridge. There weren't any signs I could remember between Bullhead City AZ and Laughlin NV.

In my experience, timezone crossing signs are more or less universal.  But, like Corco, I don't think I have ever seen a sign indicating that DST is observed.

[route56]

To save coding effort, I hard-coded the timezone offsets, and during DST changes this causes me problems since my computer is set to British time and now neither of the annual time changes are synchronized between the US and the EU. 

Why not keep your computer on UTC?

Posted 2013-03-10, 0032Z

[oscar]

Somewhat related, are there a lot of signs out there marking time zone boundaries? I have seen them marked at the Hoover Dam, and I see Nevada has a sign on northbound US 93 just after the Hoover Dam Bypass bridge. There weren't any signs I could remember between Bullhead City AZ and Laughlin NV.

IIRC, there is a pair of clocks on the Hoover Dam, to avoid confusion about whether on a particular date Arizona time is different from Nevada time.  Very helpful, IMO.

[J N Winkler]

Why not keep your computer on UTC?

I considered that, but then realized it would not solve my problem.  The servers I work with use the local time, whatever that happens to be, so if my computer were on UTC year-round, I would have one offset for three-quarters of the year and a different offset for the remainder of the year (the lone exception being a server located in Arizona).  Under the present arrangement, with the North American servers going to DST on the US schedule and my computer going to DST on the EU schedule, there are at most four weeks each year when my hard-coded offsets are wrong by one hour.

The change in the US DST schedule several years ago not only lengthened the fraction of the year that is subject to DST compared to Europe, but also ensured that DST lag between the US and Europe always shrinks (never expands) the timezone offset.  This means there is no longer any possibility of my missing a file when one of my wget scripts checks a server.  (In order for a file to be missed, the true timezone offset would have to be greater than the hard-coded offset and the file would have to be uploaded with a timestamp falling in the window between the true check time and the imputed check time.  This is also the reason I use a hard-coded offset of 8 hours for the script that checks the Arizona server--the true offset is 7 hours in the winter and 8 hours with DST, but is never greater than 8 hours.)

[tdindy88]

I love Daylight Saving Time...but wish it were still done on the first Sunday of April, not this early. Also...why isn't Indianapolis in the CENTRAL time zone? Their longitude is nearly identical to that of Nashville, which is obviously in the central time zone.

Arguing about time zones is as much of a Hooiser tradition as basketball and there will never be a clear answer on what is right for Indiana time wise. Geographically it probably should be Central, but Indianapolis is also on the same longitude as Lousiville and Grand Rapids and both are on Eastern. Everyone won't be happy with whatever decision is made, which is why lawmakers recently have brought up the talk of moving to Central...again. In the past I did enjoy letting this night pass unmarked with no changing of the clocks, but knowing where to take or add an hour across which boundary at which time of the year did get confusing for some, which is why Indiana shrugged its shoulders and said "fine we'll change our clocks too." Personally I don't get the appeal of changing clocks and wonder how everyone else stands to do it yearly, 24 hours is 24 hours and the sun will rise and set when it wants too, you can't change these two points.

[Duke87]

Having the sun stay up later in the summer is a great plus, so we need DST for that... but if we stayed on it all year, we'd have problems in the winter.

Really, the inconvenience comes from jarring everyone's schedules by changing an hour at once - studies have shown this negatively impacts your health by messing with sleep patterns. If we were to somehow make the change more gradual, you could eliminate that damage to people's circadian rhythms. In a future where every clock is somehow part of a computer, it could become practical to do something like add a minute to every third day from December 21st to June 21st, and then subtract a minute from every third day from June 21st to December 21st. The number of minutes to add/subtract could even vary by latitude.

The perfect world, ideal case would be to have our clocks such that the sun rises at the same time every day throughout the year (say, 7 AM), and only the time it sets varies seasonally.

[1995hoo]

I'd rather the changeover be on the last Sunday in March, same as it is in Europe. Eliminates the nuisance of the time difference being a different number of hours for a few weeks (even though it benefits us by making London only four hours ahead of Eastern Time). Doing business during those weeks is a nuisance because most people forget about the difference.

[Brandon]

Well Daylight Saving Time (DST) starts at 2:00 am local time on Sunday, March 10. Most of the country will spring forward an hour. There are certain areas that don't observe it (Hawaii, most of Arizona, various US territories). Some of you love it, some of you hate it, most probably don't pay attention except for twice a year. Any thoughts or opinions?

Somewhat related, are there a lot of signs out there marking time zone boundaries? I have seen them marked at the Hoover Dam, and I see Nevada has a sign on northbound US 93 just after the Hoover Dam Bypass bridge. There weren't any signs I could remember between Bullhead City AZ and Laughlin NV.

Indiana used to have signs for the change between the time zones and the areas which observed and did not observe DST along the freeways and Toll Road.

[hbelkins]

I, too, prefer DST because it gives an hour longer of daylight in the afternoons/evenings. Better not only for photography but for actually getting some work done outside when you get home from work. I'm happy that the move forward has been extended into early March and I was happy that the change back to standard time was pushed back into November. As for the lost hour of sleep, I'll just sleep an extra hour tomorrow morning and all will be well.

The change at this time of the year means I'll have an extra hour of daylight to travel in after the Monticello meet. I'm very leery of driving after dark, especially on high-speed roads like interstates, because of deer.

[corco]

The perfect world, ideal case would be to have our clocks such that the sun rises at the same time every day throughout the year (say, 7 AM), and only the time it sets varies seasonally.

You want to look a couple hundred years into the future, when the technology is fully there and developed to allow for some sort of adaptive sun based clock, I wouldn't be surprised to see our traditional concept of a linear clock go away entirely in favor of something more dynamic like that.

[english si]

If it weren't for DST, we'd not have a 6 pm sunset until March 22nd... Always find it a plus as it allows for more photography later in the day when on the road as well.

A whole 12 days gained! Pretty pointless there.

I'd rather the changeover be on the last Sunday in March, same as it is in Europe.

The March change seems about right. The EU's October change (a month after the equinox) is too late - it's dark too late in the mornings: OK, it only gives us a week or two, but the two weeks or so before the change are a nightmare for even very mild SAD sufferers that doesn't seem so bad in early November. Only good thing about the change in late October is the week where you feel a lot less depressed after the change has occurred.

IIRC the EU split is clocks back-8 weeks-equinox-12 weeks-clocks forward. 10 weeks either side feels about right (Oct more than Mar though).

I wish the country would go onto daylight savings time all year. Two years of living in Arizona made me realize the shift is more annoying than anything else, but I do prefer a later sunrise and sunset, so stick with daylight savings time.

The shift sucks, but why on earth move to DST all year round (which isn't what AZ has, which is regular time all year round)? We've, as a species, settled on lighter mornings and darker evenings - we work lopsided around noon, with more work in the evening to make sure we have the light in the mornings; we happily do stuff after dark, but before light is the dead time.

I guess one of the old arguments against DST year round is that kids can't stand out at the bus stop in the dark, but for better or worse the whole notion of kids standing out at bus stops unattended is going away anyway, so may as well just go to DST year round.

We get this one in the UK the other way around - kids shouldn't travel from school in the dark. OK, I finished later than most (1545), which counteracts my southerly latitude (~51N) but I had about two weeks of walking home in the dark and a bit less walking to in the dark (for 0845). I'd have had two months of going to school in the dark under BST, but apparently that was less of a problem than two weeks going home in the dark.

Your argument also hasn't said why DST, rather than normal time year-round.

In the UK, certainly, this 'extra hour of sunlight after work for chores' argument makes no sense, as during the 20 weeks not on DST, you might actually be able to use that extra hour in March, but not the other 16 weeks. For 12 of those weeks, under year-round Summertime/CET, you'd not have any weekday daylight exposure if in an office, whereas now that might be 6 weeks (depends on the hours you work - some people simply won't get any use of the sun during the week from September through March under DST, though might see some in the morning under GMT, due to working/commuting for too much of their time).

Having the sun stay up later in the summer is a great plus, so we need DST for that... but if we stayed on it all year, we'd have problems in the winter.

Indeed, from roughly March to September you can steal the hour in the morning and give it on the evening by shifting the clocks (I know someone who thinks it's backwards and works on the principle that there's not enough light in the evening in winter and we need to steal one from the morning, but that there's too much in the summer with DST, so don't do the shift then. He's a tool who refuses to wake up before 8 and typically wakes at about 8:45 - which is well lit for 10 months of the year, but most people are at work/school by then) - we are awake for more time p.m. than a.m. (says the person who has claimed 5 hours of the a.m. already, but won't be losing any p.m. hours. Silly New Zealand being 13 hours ahead currently, so cricket runs from 2100-0500 GMT), so light will be more useful at 7pm than 5am - but there needs to be light at 5am to move, which isn't the case in winter - when the sun does come up, we need it.

The perfect world, ideal case would be to have our clocks such that the sun rises at the same time every day throughout the year (say, 7 AM), and only the time it sets varies seasonally.

Perhaps fine south of the 49th, but north of the 50th (eg in the UK), that means very early sunsets in winter - noon in the middle works better than sunrise at hour x (also in summer, dawn at 7am, rather than 3am, means dusk at 1am, rather than 9pm (times local no DST and typical for June or July)). Also the issue of differing time differences (key one being hemispheres)

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As an aside, the UK tried year-round summer time on a trial. MPs from Southerly and Easterly locations of the UK were saying that constituents were left feeling tired due to the late dawns in the winter - not just Scotland and Norn Iron. Economically (ironically, given the supposed boost moving from Western to Central European Time causes, that it gets suggested as a way to stimulate growth) it wasn't good either, and productivity was down. Illness went up, too, IIRC what I gleaned from the Hansard debate. The vote to make it permanent didn't happen as the Government didn't want to be embarrassed. But then we get proposals twice a year to repeat the folly with no reference back.

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This is interesting on this issue - massively attacks Spain being on CET (see also Indiana on EST - though not having DST did help) as unnatural and dangerous.

[Desert Man]

From what I heard of Daylight Savings time, Indiana (or one part of the state) doesn't observe DST from a tale of farmers concerned their livestock will be confused by the time change. I knew AZ doesn't do DST for unknown reasons AFAIK, but each municipality and state has a choice to observe (or not adhere to) Daylight Savings time. All we know is we lose a hour of sleep tomorrow and be harder to get up for work this Monday.

[swbrotha100]

From what I heard of Daylight Savings time, Indiana (or one part of the state) doesn't observe DST from a tale of farmers concerned their livestock will be confused by the time change. I knew AZ doesn't do DST for unknown reasons AFAIK, but each municipality and state has a choice to observe (or not adhere to) Daylight Savings time. All we know is we lose a hour of sleep tomorrow and be harder to get up for work this Monday.

All of Indiana started doing DST back in 2006. Before that, only the Eastern Time Zone in Indiana stayed on standard time all year.

In Arizona, there's no desire for an extra hour of sun in the summer months due to how hot it gets. DST was observed in 1967 and hasn't been observed since (except for the Navajo Nation, in the northeast part of the state.

[english si]

All of Indiana started doing DST back in 2006. Before that, only most of the Eastern Time Zone in Indiana stayed on standard time all year.

Fixed that for you.

In many ways it was weird - Indiana is natural Central territory and was (mostly) effectively on Central Time with winter DST...

[formulanone]

All the arguments about Daylight Savings Time are as tedious as complaints about Valentine's Day and the commercialization of Christmas.

[Brandon]

All of Indiana started doing DST back in 2006. Before that, only most of the Eastern Time Zone in Indiana stayed on standard time all year.

Fixed that for you.

In many ways it was weird - Indiana is natural Central territory and was (mostly) effectively on Central Time with winter DST...

There are still a lot of Hoosiers who want to go back to the way time in Indiana was.  It's quite interesting as time in Indiana has gone back and forth between Eastern and Central Time quite a few times.

[Alex]

If it weren't for DST, we'd not have a 6 pm sunset until March 22nd... Always find it a plus as it allows for more photography later in the day when on the road as well.

A whole 12 days gained! Pretty pointless there.

The point was that because of our location in Central Time Zone, we get the shaft with uber early sunrises and sunsets. A 6 pm sunset on March 22nd is the latest of any place I have lived which has been in the northeast/mid-atlantic, southeast, and southwest. 6 pm is my "reasonable sunset time", so its a staple for me to look forward to it. Growing up in Newark, DE, I always looked forward to March 7th, when 6 pm sunsets returned.

[cpzilliacus]

I'd rather the changeover be on the last Sunday in March, same as it is in Europe. Eliminates the nuisance of the time difference being a different number of hours for a few weeks (even though it benefits us by making London only four hours ahead of Eastern Time). Doing business during those weeks is a nuisance because most people forget about the difference.

Absolutely correct. 

Why the D.C. politicians had to set the Daylight Time/Standard Time changeovers to be different from our friends in the EU was (and is) a real mystery.

[vdeane]

I've never understood why anyone would want extra daylight in the mornings.  Realistically, all you use the morning for is dragging yourself out of bed and into an artificially-lighted school/work place.  All that daylight outside is wasted while you're inside.  Once I enter the workforce, I fully expect that a good chunk of the year I won't see a single speck of daylight thanks to "standard" time (why is it still called that anyways?  There's nothing standard about a time that is used only 5 months of a 12 month year).  All standard time does is give everyone seasonal effective disorder.

It doesn't help that my sleep cycle just doesn't care about sunlight - I'm naturally wired to go to sleep at 2/3 AM and wake up around 9/10 AM, everything else be damned.  It makes getting up in the morning really hard regardless of the amount of sunlight.

Also, it is NOT fun to enter a lecture hall at 4 with it looking like noon and exit at 5 with the sky looking like midnight.

[DaBigE]

Just move the clocks 30-minutes and keep it there. Forever.

[mgk920]

The perfect world, ideal case would be to have our clocks such that the sun rises at the same time every day throughout the year (say, 7 AM), and only the time it sets varies seasonally.

You want to look a couple hundred years into the future, when the technology is fully there and developed to allow for some sort of adaptive sun based clock, I wouldn't be surprised to see our traditional concept of a linear clock go away entirely in favor of something more dynamic like that.

Ben Franklin was chocked full of ahead-of-his-time ideas, but this is one that, IMHO, he should have kept to himself.  Don't reset your clocks, reset your schedule!



(BTW, BF promoted the idea as a way of saving energy - in his day it was candle wax in the evenings.)

I kind of think that having the whole World on UTC is an idea that has merit.



Also, 'standard time' was first set up by railroads due to the difficulties in train scheduling and dispatching when every little town along the way had their clocks set to their local 'solar' time, which varied a couple of minutes from town to town as one traveled eastward or westward.  This wasn't a problem when *nothing* traveled faster than a horse could run, but once the 19th century got going in earnest, it became an issue.

In North America, after much private-sector horse-trading (mainly involving railroad companies), time was 'standardized' at noon EST on 1883-11-18 when a time signal was telegraphed across the USA and Canada and clocks were reset to the top of the hour of whatever time zone they were in.

Daylight Saving Time was adopted in the USA for one year in 1918 but repealed the following year and was not re-instated until WWII.

---------------------------

And yes, there are days when I wished that I could dig up and wring the neck of whoever it was who discovered the principal of the pendulum clock escapement mechanism!  GRRRrrrrr....



Mike