DST (2018)

[20160805]

People are generally saying one of two things:
1. Keep it the way it is.
2. Permanent DST.
Neither involves moving the summer to Standard Time.

IIRC, 20160805, kphoger, and possibly Rothman have advocated abolishing DST altogether. A number of others have expressed support for DST with the pre-2007 time frame (first Sunday in April to last Sunday in October).

However, you are correct that most people have supported one of the two positions above. I didn't really have an opinion at the beginning of the thread, but now I'm decidedly in favor of (1), despite tradephoric's efforts. 

Side note: I never realized that the diagonal slant of the East Coast was exactly the right amount so that the sun would set at almost exactly the same time on the solstice for most places on the coast.

Interesting!

This is accurate (at least regarding my own opinion).  19:30 is plenty late enough of a summer sunset for me - plenty of light at both commutes, but not light so late I can't sleep at night.  In my ideal pipe-dream custom latitude scenario, my latest sunset would actually be at 18:43. (Latitude 20*N, clock time-solar time offset of 0)

[tradephoric]

Nah.  'The problem' is that people have expectations of where the sun should be based on having personal schedules that are fixed to specific numbers on the clock.

That problem could be fixed if people revised their schedules, rather than seeking to revise their clocks.

Exactly!  At this point we should have Trump flip a coin in the rose garden of the White House- one side labeled permanent DST and the other labeled standard time.  Whatever side it lands on we stick with it and whoever b@#$@S about the new setup will just have to learn to adjust.  I'm being a little facetious, because I do think there is benefit going to permanent DST for the simple fact that it would allow individual states to still opt-out of DST entirely (as Arizona and Hawaii currently do).  Also, permanent DST wouldn't be that radical of a change since Americans already spend roughly 65% of the year in DST (apart from Arizona and Hawaii, who could continue to stay on standard time if we went to permanent DST).  Ok, i'm going to change my idea... Trump should flip a coin that has "permanent DST" labeled on both sides.   
 
So the two times a year when the clocks change, inevitably a certain percentage of traffic signals aren't adjusted to re-sync to the new time.  You have school lights flashing when they shouldn't be or school speed limit signs not coming on during school start times.  Or the signal is running a "light"  traffic dial during the middle of rush hour.  It's almost a guarantee that for 2 weeks out of the year, some traffic signals are going to be out of wack (because for each biannual clock change, it takes a week for road agencies to diagnose the problem and then send someone out to reset the clock).  Maybe this is another reason why there is a spike in crashes after DST time changes.  Yes, there are ways to prevent this from happening in the controller programming, but it requires the controller to be programmed correctly.  For a city with thousands of traffic signals, do you really think every traffic signal will be programmed correctly?  All it takes is a few signals out of sync to mess up your drive.  So if you ever wondered why your drive into work sucked right after a time change, this could be the reason.  Just another reason to get rid of the time changes. 

[jeffandnicole]

Whatever side it lands on we stick with it and whoever b@#$@S about the new setup will just have to learn to adjust.

No matter what side it is, 80% of the population will bitch about it.

[kalvado]

Whatever side it lands on we stick with it and whoever b@#$@S about the new setup will just have to learn to adjust.

No matter what side it is, 80% of the population will bitch about it.

50% of bitching would be about "turning things up side down AGAIN!!"

[kkt]

Nah.  'The problem' is that people have expectations of where the sun should be based on having personal schedules that are fixed to specific numbers on the clock.

That problem could be fixed if people revised their schedules, rather than seeking to revise their clocks.

Exactly!  At this point we should have Trump flip a coin in the rose garden of the White House- one side labeled permanent DST and the other labeled standard time.  Whatever side it lands on we stick with it and whoever b@#$@S about the new setup will just have to learn to adjust.  I'm being a little facetious, because I do think there is benefit going to permanent DST for the simple fact that it would allow individual states to still opt-out of DST entirely (as Arizona and Hawaii currently do).  Also, permanent DST wouldn't be that radical of a change since Americans already spend roughly 65% of the year in DST (apart from Arizona and Hawaii, who could continue to stay on standard time if we went to permanent DST).  Ok, i'm going to change my idea... Trump should flip a coin that has "permanent DST" labeled on both sides.   
 
So the two times a year when the clocks change, inevitably a certain percentage of traffic signals aren't adjusted to re-sync to the new time.  You have school lights flashing when they shouldn't be or school speed limit signs not coming on during school start times.  Or the signal is running a "light"  traffic dial during the middle of rush hour.  It's almost a guarantee that for 2 weeks out of the year, some traffic signals are going to be out of wack (because for each biannual clock change, it takes a week for road agencies to diagnose the problem and then send someone out to reset the clock).  Maybe this is another reason why there is a spike in crashes after DST time changes.  Yes, there are ways to prevent this from happening in the controller programming, but it requires the controller to be programmed correctly.  For a city with thousands of traffic signals, do you really think every traffic signal will be programmed correctly?  All it takes is a few signals out of sync to mess up your drive.  So if you ever wondered why your drive into work sucked right after a time change, this could be the reason.  Just another reason to get rid of the time changes. 

Sorry, but just because you keep saying your way should be the only way isn't going to make it happen.  I like the long summer evenings.  I am not fond of being woken up by full sun at 5:10 AM, I would like still less being woken up by full sun at 4:10.

Changing the few clocks that still need to be changed manually takes about 10 minutes, twice a year.  That's a small price to pay for about four months of daylight at a more useful hour of the day.

Adopting the EU's change dates would be a plus.  But abandoning a shift altogether is a nonstarter as far as I'm concerned.

People can't easily just change their personal schedule whenever they want.  People live in complex societies with many activities that depend on each other.  When my work schedule shifts to DST, I need my child's school schedule, the bus schedule, the train schedule, opening hours for grocery stores, restaurants, and dry cleaners to all change at the same time.

For people who don't like changing their clocks, they could keep UTC.  No shifting, same time kept all over the world.  This is what astronomers and airlines that operate worldwide do.  The fact that so few other people keep UTC suggests that most people do care about the sun having some relationship to the clock.

No matter what side it is, 80% of the population will bitch about it.

Yep.   

[webny99]

Whatever side it lands on we stick with it and whoever b@#$@S about the new setup will just have to learn to adjust.

No matter what side it is, 80% of the population will bitch about it.

From my observation (friends/family/this thread), less than 80% are complaining about DST as it is currently. Which is why I think it might be the best we can do.

[webny99]

Changing the few clocks that still need to be changed manually takes about 10 minutes, twice a year.  That's a small price to pay for about four months of daylight at a more useful hour of the day.

Thank you. I, too, fail to see what is so hard, complicated, etc., about changing the clocks. It's an hour, one, single hour. My schedule varies by at least that much from a weekday to a weekend, all the time.

Adopting the EU's change dates would be a plus. But abandoning a shift altogether is a nonstarter as far as I'm concerned.

Any shift is better than no shift. Year-round DST would be bad in the winter, year round standard time would be worse in the summer. The price of maintaining the same time year-round is too high either way.

[tradephoric]

Changing the few clocks that still need to be changed manually takes about 10 minutes, twice a year.  That's a small price to pay for about four months of daylight at a more useful hour of the day.

You are downplaying the negative effects that time changes can have on traffic flow.  It's not just the 10 minutes it takes to resync the clocks at a traffic control device that was missed during the time change... it's the days it may take for motorists to see the problem, report it to the agency, and then for the agency to dispatch a crew out to resync the clocks.  That could take 1 week and 10 minutes... if not longer.  The problem of out of sync clocks at traffic control devices after a time change can be alleviated if the system is connected to a central TOC, but not all agencies have the funds to manage such a system.  And those systems still require for the signals to be online, and if they are not online during the time change they can still easily get out of sync.  I personally see instances of out of sync clocks at traffic control devices for days after a time changes, and I can't imagine it's only a problem around here. 

Apart from out of sync clocks, a driver who is driving home from work in daylight on Friday is potentially now driving home in darkness the exact same time the following Monday after the time change.  Is there any wonder there's a spike in crashes after a time change?  People haven't had time to adjust to driving home from work at night as opposed to the day... and millions of motorists are dealing with this disruptive change all at once.   I know the argument is also that people are tired after a time change, which leads to more crashes, but are there spikes in crashes happening during both fall back and spring forward?  If there are spikes during both time changes (and I'm not sure of the answer), then that would suggest the spike in crashes could be more than just people being tired after a time change (because people have gained an hour of sleep in one instance).   I'll try to find the answer.

[tradephoric]

OK, admittedly this is the first research paper i stumbled across, but it did report that there was a significant increase in accidents for the Monday immediately following the spring shift to DST AND significant increase in number of accidents on the Sunday of the fall shift from DST.  So is the disruptive changes in lighting conditions or sleep patterns leading to the increases in crashes after a time change?  Either way, there are significant increases in crashes after BOTH time changes. 

Fatal accidents following changes in daylight savings time: the American experience

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.
https://www.sciencedirect.com/science/article/pii/S1389945700000320

[MikeTheActuary]

A few studies have suggested that the shock of a time change can be hazardous to your health: https://www.timeanddate.com/time/dst/daylight-saving-health.html

It's not a big impact on any one person, but taken across all the areas that do do time-changes......

[vdeane]

Changing the few clocks that still need to be changed manually takes about 10 minutes, twice a year.  That's a small price to pay for about four months of daylight at a more useful hour of the day.

Thank you. I, too, fail to see what is so hard, complicated, etc., about changing the clocks. It's an hour, one, single hour. My schedule varies by at least that much from a weekday to a weekend, all the time.

Adopting the EU's change dates would be a plus. But abandoning a shift altogether is a nonstarter as far as I'm concerned.

Any shift is better than no shift. Year-round DST would be bad in the winter, year round standard time would be worse in the summer. The price of maintaining the same time year-round is too high either way.

Any shift?  I can have some fun with that... how about DST on June 21 and standard time the other 364 days of the year (or standard time December 21 and DST the rest of the year)?  Or shifting by 12 hours instead of 1, flipping day and night for half the year?

Time for a "most absurd DST schedules" thread.

[hotdogPi]

Time for a "most absurd DST schedules" thread.

[hbelkins]

Resetting clocks twice a year is no big deal. My power goes out a lot more often than twice a year, which necessitates resetting all clocks in the house.

[jeffandnicole]

Time for a "most absurd DST schedules" thread.

Standard time: Cloudy, rainy days.

DST: Sunny, nice days.

[kkt]

Time for a "most absurd DST schedules" thread.

Genius.   

[webny99]

Any shift is better than no shift. Year-round DST would be bad in the winter, year round standard time would be worse in the summer. The price of maintaining the same time year-round is too high either way.

Any shift?

When I say any, I mean it in the sense that the exact date doesn't matter; as long as the entire summer is on DST and the entire winter is on standard time and the shift happens somewhere in between.

[kkt]

OK, admittedly this is the first research paper i stumbled across, but it did report that there was a significant increase in accidents for the Monday immediately following the spring shift to DST AND significant increase in number of accidents on the Sunday of the fall shift from DST.  So is the disruptive changes in lighting conditions or sleep patterns leading to the increases in crashes after a time change?  Either way, there are significant increases in crashes after BOTH time changes. 

Fatal accidents following changes in daylight savings time: the American experience

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.
https://www.sciencedirect.com/science/article/pii/S1389945700000320

That's a barely measurable level of significance.  I'd be interested in statistics on how many more fatal accidents there are from rush hours being in darkness more days due to observing DST year-round.

[english si]

This is accurate (at least regarding my own opinion).  19:30 is plenty late enough of a summer sunset for me - plenty of light at both commutes, but not light so late I can't sleep at night.  In my ideal pipe-dream custom latitude scenario, my latest sunset would actually be at 18:43. (Latitude 20*N, clock time-solar time offset of 0)

Good grief - you'll hate living here. It's 22:09 now. The streetlights turned on just a few minutes ago. I can still see a bit of pink in the sky and much of it is light-blue grey, going to dark blue grey. It's dark, but not that dark (it has got noticeably darker the last 15 minutes or so). You could sit outside without artificial light and see other people's faces as you talked.

[tradephoric]

That's a barely measurable level of significance.  I'd be interested in statistics on how many more fatal accidents there are from rush hours being in darkness more days due to observing DST year-round.

I disagree with your assumption that there would be more rush hours in darkness if year-round DST was observed.  After all, more darkness during AM rushes with permanent DST would be offset by more light during PM rushes.  I already showed how permanent DST would minimize the total minutes Awake in Darkness (AID) and the minutes Sleeping in Light (SIL) compared to standard time.  Minimizing the total minutes Awake in Darkness (AID) also minimizes the amount of minutes that American's are potentially driving in darkness (which in theory should result in fewer fatal crashes... or at the very least a reduced fatality rate). 

I put together a list of dawn/dusk times for the top 20 metro regions in America.  I wanted to consider the lighting effects that winter DST would have on early birds (wake at 05:00, go to bed at 21:00) and night owls (wake at 08:00, go to bed at midnight).  Running DST during the winter greatly minimizes the total minutes Awake in Darkness (AID) and the minutes Sleeping in Light (SIL) compared to standard time.





*The early bird in all 20 metro regions is never sleeping in light (SIL) regardless if it's running DST or Standard time.  OTOH, night owls are sleeping in light (SIL) in all 20 metro regions when running Standard time during the winter.

*Detroit would experience the latest dawn out of the top 20 metro regions if the nation observed DST during the winter.  The dawn would begin in Detroit at 8:26AM.

[vdeane]

My evening commute is never anything darker than civil twilight (which is basically daylight, really) year round.

[webny99]

My evening commute is never anything darker than civil twilight (which is basically daylight, really) year round.

Same here, and I work 7:30 to 4:30.
October and December mornings, on the other hand, are almost impossible to commute fully in the light (15 minutes more so here than in Albany).
Year round DST would definitely cause a net increase in dark commutes for me; there's just no way around it. Sure, my evening commutes would have more light, but they wouldn't improve from fully or mostly dark to fully or mostly light, so the position of the sun is irrelevant.

[tradephoric]

The PM rush is typically heavier than the AM rush because more people are out and about in the evenings running errands.  In that regard it makes sense to favor more daylight during the PM rush.  OTOH, the morning commute is full of motorists driving straight to work, worried about if they will make it on time.  They aren't stopping at a grocery store before work to buy milk. 

Morning routine: A=leave home; B=stop at Starbucks; C=arrive at work (it becomes a direct A-B route if you aren't a coffee drinker). 

Afternoon routine: A=leave work; B=stop at the gas station; C=stop at home depot; D=meet friends for happy hour; E=hit the casino; G=call your wife to let her know you are working late

... point is there is a lot more things to do in the evenings and you never really know what errands will have you running around town after work.   The friends you met up with after work convince you to hit the casino, but you haven't been there for a few years.  Wouldn't you rather have daylight driving that "unfamiliar" route?  OTOH, the familiar route you've taken to the job you've been working the past 3 years... you could probably drive that in your sleep.  The light is almost wasted in the morning on that direct familiar route. 

[jeffandnicole]

Afternoon routine: A=leave work... E=hit the casino; G

Thank goodness for online gambling.  You can gamble while sitting in traffic!

[Scott5114]

Afternoon routine: A=leave work... E=hit the casino; G

Thank goodness for online gambling.  You can gamble while sitting in traffic!

Not enough for some people. I've seen people play a slot machine app on their phone while sitting in front of an actual slot machine they're playing. Apparently they need something to fill the time waiting for the reels to stop.

[tradephoric]

Assemblyman Kansen Chu, who introduced AB 807 states that "If signed by the governor, the bill will bring California closer to abolishing the outdated practice of switching our clocks in the fall and spring."  He doesn't say that it gets California one step closer to abolishing DST, because that isn't Kanen's ultimate goal. Who in LA wants 4:41 AM sunrises and 7:07 PM sunsets during the summer solstice?  Those would be the sunrise/sunset times in LA if DST was abolished.  Just don't pay that much attention to the poorly worded headline... switch "end of daylight saving time" with "end of clock changes"

End of daylight saving time inches closer in California
http://www.sacbee.com/news/politics-government/capitol-alert/article213187609.html

The state Senate on Thursday approved a proposal to ask voters to repeal a 70-year-old initiative that set a biannual clock change in California and give lawmakers the power to adjust the time with a two-thirds vote.

"If signed by the governor, the bill will bring California closer to abolishing the outdated practice of switching our clocks in the fall and spring," said Assemblyman Kansen Chu, D- San Jose, who introduced Assembly Bill 807.

AB 807 allows the Legislature to amend daylight saving time with a two-thirds vote in the future. If voters approve the ballot measure, Chu, or another lawmaker, would need to introduce a new bill to establish a permanent daylight saving time.

The new proposal would have to clear the Senate and the Assembly and receive the governor's signature. Then Congress would have to take action to sanction the law and allow states to adopt a year-round daylight saving time.