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How much daylight you lose depend highly on what latitude you are living. In California, daylight savings actually makes sense, it's a noticeable boost of dayl

How much daylight you lose depend highly on what latitude you are living. In California, daylight savings actually makes sense, it's a noticeable boost of daylight for your office commute in the winter. In northern Europe, it makes absolutely no sense, because the darkness consumes everything anyway. It takes about a week or two for sunrise to be at the same time it was before the clock adjustment each fall. It's pretty useless.

paulsutter 8y ago
If “daylight savings” time is so great, why not keep it all year round? Why change at all?
- runarberg 8y ago
  Please don’t do that. Sleep is really important, and waking up before sunrise is potentially detrimental to overall sleep in the population.
  - henrikschroder 8y ago
    Yeah, uh, that doesn't work in northern Europe, or you'd have everyone asleep until 10. On a meta note: It is always super interesting to me how fundamental people think that day length is, if they've never experienced living at different latitudes. The variations are absolutely enormous, and create very different mindsets. That said, seasonal mood disorders are very common in northern Europe for a reason. Going to school or going to work hours before sunrise in the winter is just the way of things in northern Europe. You don't have a choice in the matter. The flipside is that having full daylight at 10 in the evening during summer is also just the way of things, and the almost non-existant night is a complete mindfuck for people used to less variations in day length.
    - runarberg 8y ago
      you’re not wrong, however this is a gross oversimplification. If you are on a permanent daylight savings time at high latitudes, you will have more people staying up late and waking up early for a longer period of the year. The difference is not negligible. In fact Iceland (currently on permanent daylight savings time; where I have lived most of my life) is considering moving the clock closer to solar time. They are citing public health reasons for the move.
  - henrikschroder 8y ago
    Also do check the daylight graphs I posted in other comments, but here's an example from northern Norway: https://www.timeanddate.com/sun/norway/narvik https://www.timeanddate.com/sun/norway/narvik For a month of winter, there is no daylight at all. It is literally impossible to wake up after sunrise, because sunrise doesn't happen for an entire month.
    - ghaff 8y ago
      In all fairness, that's northern Norway which is not where most people live. But the general point is valid. It's mostly the northern mid-latitudes where people want to optimize the clock relative to the sun for different times of year. Further north and further south, it doesn't matter as much (for different reasons).
    - runarberg 8y ago
      The adverse effects of sleep deprivation accumulate. It does make sense to minimize the time you have to wake up before daylight.
- lultimouomo 8y ago
  Because getting into an office when it's still dark in winter is even more depressing than having less hours of light in the evening in summer
  - deleted 8y ago
    [deleted]
- henrikschroder 8y ago
  The rationale for daylight savings in a southern latitude like California is this: People generally wake up, and go to work the first thing in the morning. They would like to travel to work after sunrise. They would also like to maximize the amount of daylight they get to enjoy outside of work. This means that in the summer, all the daylight before waking up is "wasted" so you want to move solar noon forward. But if you move it too far, it'll be pitch black when people get to work in the winter, which is why you then have daylight savings to move solar noon back a bit. If you live further south, like Hawaii, the difference in length of day between winter and summer is very small, so you can't shift solar noon around. Therefore, Hawaii doesn't do daylight savings. If you live further north, like Sweden, the difference in length of day between winter and summer is enormous, and in the summer the sun rises at like 3 in the morning with daylight savings, and in the winter the sun rises at 10 with standard time, and the rate of daylight change around the equinoxes is huge, so the effect only lasts a week or two. It makes absolutely no sense to have daylight savings there, and the EU parliament making it not mandatory for countries is a step in the right direction, i.e. abolish the useless thing in Sweden. Spain and the other Mediterranean countries could maybe keep it for all I care, but Spain has a weirdly skewed solar noon anyway...
  - paulsutter 8y ago
    Since it’s getting dark earlier after work, how does this maximize daylight outside of work? > They would like to travel to work after sunrise. They would also like to maximize the amount of daylight they get to enjoy outside of work.
    - function_seven 8y ago
      Well the seasons don't give us much wiggle room here, so the thinking is to (1) make sure the sun has risen when you set off for work. If there's extra sunlight still, then (2) let's have that after work. In the winter, you can't have both, so you pick #1. In the summer, you have "extra" sunlight that's being wasted on the sleeping, so you shift it to after work and get #1 and #2.
    - henrikschroder 8y ago
- ghaff 8y ago
  The main reason is probably, especially at mid-northern latitudes (where a huge number of people live), absent DST conventional work/school hours would mean that biasing sunlight hours on the late side--which many/most people prefer in the summer--implies it would be dark when people leave their house on a winter morning. Among other things, this means kids wait for buses or go to school in the dark. Personally, I'd be fine with shifting a time zone or two east and eliminating DST but I understand why a lot of people wouldn't.
- Reason077 8y ago
  > "If “daylight savings” time is so great, why not keep it all year round?" This is exactly what many countries are proposing. Rather than abolish summer time, just make it permanent.
  - mac01021 8y ago
    Which is exactly the same as using standard time all year and then moving all your appointments 1 hour earlier for the rest of eternity. Except that "noon" ceases to mean the time when the sun is highest in the sky equidistant between sunrise and sunset and "midnight" ceases to be the middle of the night. In this respect, standard time makes more sense. In no respect does "daylight time" make more sense. Still, anything that makes us stop changing the clocks twice a year is fine with me.
    - henrikschroder 8y ago
      Solar noon coincides with noon for a pretty small amount of places, take a look at this map: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV2.png http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV... Only the thin stripes of white have it, for every other place solar noon is off by minutes, if not hours.
      - mac01021 8y ago
        That's true. But almost everywhere in the continental US is within minutes.
2038AD 8y ago
>In California, daylight savings actually makes sense, it's a noticeable boost of daylight for your office commute in the winter. So the plan is that instead of people working hours which suit and know about it we agree on a weird collective lie and get everyone to perform the clock-adjusting ritual
- henrikschroder 8y ago
  It's not so weird, because the question "what time is it?" has a single authoritative source, and it can only be answered by a single authoritative source. (NIST in the US, right?) But the question "when should we go to work?" doesn't have a single authoritative source, it all depends, it's all culture, it's all customs, everyone is free to do their own thing, but protestant work ethic bla bla bla, and here we are with most people starting work at 9, and if you don't, you're a weird slacker. Yes, agreeing to start work at 10 in the winter is completely functionally equivalent with moving the clock forward an hour during winter, but it's just mentally impossible to implement because humans are weird like that.
- function_seven 8y ago
  > So the plan is that instead of people working hours which suit and know about it we agree on a weird collective lie and get everyone to perform the clock-adjusting ritual Well yeah. Much simpler to make the adjustment once, at an agreed upon time of year, than to have a hodgepodge of different companies, schools, retailers, bagel shops, etc. all move their hours independently. In that case you have a first-mover problem and nobody adjusts. It's not a lie anymore than time zones themselves are lies. (i.e. Time zones don't follow strict longitudinal lines, they follow political boundaries instead, and are often wider or narrower than the 15° they "should" be)
  - 2038AD 8y ago
    >Well yeah. Much simpler to make the adjustment once, at an agreed upon time of year, than to have a hodgepodge of different companies, schools, retailers, bagel shops, etc. all move their hours independently I'm not sure it is simpler to be honest. It's normal for companies to have different starting hours. I'm just about to move to a job where my official start is half an hour later. That increases to an hour with the actual time time I currently get into work. Even without that, daylight savings is hodgepodge with different countries starting at different times. Ironically anti-daylight-savings people would be welcoming the current news as good when it will likely just mean more countries having daylight savings but not being consistent. >It's not a lie anymore than time zones themselves are lies I can't really disagree.
mhenr18 8y ago
Daylight saving time doesn't apply to the winter though. Winter time is standard time, and DST is in effect during the summer months to better make use of the extra light available during summer by winding clocks an hour forward. The idea being that you get an extra hour of sun in the afternoon.
- henrikschroder 8y ago
  Yes, sorry, moving back to standard time provides a boost in winter. Both clock adjustments provide different benefits, which is why we do both, to get both benefits. Abolishing DST means you pick one of the two.
- zaarn 8y ago
  The idea was actually to save power by extending the part of the day that had sunlight.
pmontra 8y ago
I agree. I see why countries in northern Europe have little use for daylight savings: they have darkness in the morning in winter and sun well before everybody's awake in summer whenever they use daylight savings or not. In southern Europe it's different (I live there), especially because those countries tend to center their day not around noon but to later hours: lunch starting between 13:00/15:00 and dinner between 21:00/23:00. Spain basically lives with a double summer time. Italy has a gradient between North (earlier, 1 PM) and South (later). I don't live particularly in the south but if I have to choose I'll pick summer time for all the year, and maybe double of it. Sun at 6 AM is wasted, darkness at 7 PM is depressing. We could end up with two horizontal time zones. UTC+1 in the north and UTC+2 in the south. By the way, the few people from my country that voted in that poll were keen about keeping daylight savings.
- LoSboccacc 8y ago
  Same for me, if they drop the dst I hope they keep the summer time in Italy, because extended light at evenings is awesome and more useful than extended light when I'm sitting in the office early in the morning
  - bonzini 8y ago
    But darkness at 8.30AM is also depressing. For some countries, certainly not all of them, daylight savings time is a blessing and well worth the hassle. Those countries would probably benefit from using standard time and moving everything thirty minutes earlier (effectively a 30 minute off time zone), but it's hard to implement such a sweeping change.
    - LoSboccacc 8y ago
      but here's the thing, in winter I still have to go to work in the dark
      - bonzini 8y ago
        What time do you leave home in the winter? Both me and my wife leave at 8:15 AM, and it's already light in Milan.
dragonwriter 8y ago
> In California, daylight savings actually makes sense, it's a noticeable boost of daylight for your office commute in the winter. Winter is in standard time, so DST has no effect on it. (Also, the standard time evening commute in CA is in darkness, and wouldn't be if it was in DST, so even if you are comparing the status quo against permanent DST rather than permanent standard time, that's still wrong.) DST—“Summer Time”—maximizes post-9-5-working-hours daylight time (to promote shopping and other commercial and recreational activity) in summer, not commute-convenient daylight time in winter.
flurdy 8y ago
Seems like they needed a latitude based timezones on top of longtitude timezones... A grid based timezone system. Sounds like it would pay for a lot of developers careers... And a nightmare. I grew up at 59 degrees north latitude. Daylight savings was pointless. Wintertime I'd go school in the dark (8am) and go home in the twilight (2pm). Lunch time was bright though... My parents grew up at 70 degrees north, where daylight saving is totally useless as there is no daylight in the middle of winter. I now live at 51 degrees latitude and my kids go to school in daylight as school start an hour later here. For a few weeks in the winter daylight saving does make a tiny difference for their morning but not afternoon. But as an adult daylight saving always went the wrong way as it means evenings get darker sooner. I don't care if I commute in the dark in the morning, but I do prefer to do things after school/work in some daylight/twilight.
rudde 8y ago
We have these other seasons in northern Europe, called autumn and spring.

paulsutter 8y ago

If “daylight savings” time is so great, why not keep it all year round? Why change at all?

runarberg 8y ago
Please don’t do that. Sleep is really important, and waking up before sunrise is potentially detrimental to overall sleep in the population.
- henrikschroder 8y ago
  Yeah, uh, that doesn't work in northern Europe, or you'd have everyone asleep until 10. On a meta note: It is always super interesting to me how fundamental people think that day length is, if they've never experienced living at different latitudes. The variations are absolutely enormous, and create very different mindsets. That said, seasonal mood disorders are very common in northern Europe for a reason. Going to school or going to work hours before sunrise in the winter is just the way of things in northern Europe. You don't have a choice in the matter. The flipside is that having full daylight at 10 in the evening during summer is also just the way of things, and the almost non-existant night is a complete mindfuck for people used to less variations in day length.
  - runarberg 8y ago
    you’re not wrong, however this is a gross oversimplification. If you are on a permanent daylight savings time at high latitudes, you will have more people staying up late and waking up early for a longer period of the year. The difference is not negligible. In fact Iceland (currently on permanent daylight savings time; where I have lived most of my life) is considering moving the clock closer to solar time. They are citing public health reasons for the move.
- henrikschroder 8y ago
  Also do check the daylight graphs I posted in other comments, but here's an example from northern Norway: https://www.timeanddate.com/sun/norway/narvik https://www.timeanddate.com/sun/norway/narvik For a month of winter, there is no daylight at all. It is literally impossible to wake up after sunrise, because sunrise doesn't happen for an entire month.
  - ghaff 8y ago
    In all fairness, that's northern Norway which is not where most people live. But the general point is valid. It's mostly the northern mid-latitudes where people want to optimize the clock relative to the sun for different times of year. Further north and further south, it doesn't matter as much (for different reasons).
  - runarberg 8y ago
    The adverse effects of sleep deprivation accumulate. It does make sense to minimize the time you have to wake up before daylight.
lultimouomo 8y ago
Because getting into an office when it's still dark in winter is even more depressing than having less hours of light in the evening in summer
- deleted 8y ago
  [deleted]
henrikschroder 8y ago
The rationale for daylight savings in a southern latitude like California is this: People generally wake up, and go to work the first thing in the morning. They would like to travel to work after sunrise. They would also like to maximize the amount of daylight they get to enjoy outside of work. This means that in the summer, all the daylight before waking up is "wasted" so you want to move solar noon forward. But if you move it too far, it'll be pitch black when people get to work in the winter, which is why you then have daylight savings to move solar noon back a bit. If you live further south, like Hawaii, the difference in length of day between winter and summer is very small, so you can't shift solar noon around. Therefore, Hawaii doesn't do daylight savings. If you live further north, like Sweden, the difference in length of day between winter and summer is enormous, and in the summer the sun rises at like 3 in the morning with daylight savings, and in the winter the sun rises at 10 with standard time, and the rate of daylight change around the equinoxes is huge, so the effect only lasts a week or two. It makes absolutely no sense to have daylight savings there, and the EU parliament making it not mandatory for countries is a step in the right direction, i.e. abolish the useless thing in Sweden. Spain and the other Mediterranean countries could maybe keep it for all I care, but Spain has a weirdly skewed solar noon anyway...
- paulsutter 8y ago
  Since it’s getting dark earlier after work, how does this maximize daylight outside of work? > They would like to travel to work after sunrise. They would also like to maximize the amount of daylight they get to enjoy outside of work.
  - function_seven 8y ago
    Well the seasons don't give us much wiggle room here, so the thinking is to (1) make sure the sun has risen when you set off for work. If there's extra sunlight still, then (2) let's have that after work. In the winter, you can't have both, so you pick #1. In the summer, you have "extra" sunlight that's being wasted on the sleeping, so you shift it to after work and get #1 and #2.
  - henrikschroder 8y ago
ghaff 8y ago
The main reason is probably, especially at mid-northern latitudes (where a huge number of people live), absent DST conventional work/school hours would mean that biasing sunlight hours on the late side--which many/most people prefer in the summer--implies it would be dark when people leave their house on a winter morning. Among other things, this means kids wait for buses or go to school in the dark. Personally, I'd be fine with shifting a time zone or two east and eliminating DST but I understand why a lot of people wouldn't.
Reason077 8y ago
> "If “daylight savings” time is so great, why not keep it all year round?" This is exactly what many countries are proposing. Rather than abolish summer time, just make it permanent.
- mac01021 8y ago
  Which is exactly the same as using standard time all year and then moving all your appointments 1 hour earlier for the rest of eternity. Except that "noon" ceases to mean the time when the sun is highest in the sky equidistant between sunrise and sunset and "midnight" ceases to be the middle of the night. In this respect, standard time makes more sense. In no respect does "daylight time" make more sense. Still, anything that makes us stop changing the clocks twice a year is fine with me.
  - henrikschroder 8y ago
    Solar noon coincides with noon for a pretty small amount of places, take a look at this map: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV2.png http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV... Only the thin stripes of white have it, for every other place solar noon is off by minutes, if not hours.
    - mac01021 8y ago
      That's true. But almost everywhere in the continental US is within minutes.

2038AD 8y ago

>In California, daylight savings actually makes sense, it's a noticeable boost of daylight for your office commute in the winter. So the plan is that instead of people working hours which suit and know about it we agree on a weird collective lie and get everyone to perform the clock-adjusting ritual

henrikschroder 8y ago
It's not so weird, because the question "what time is it?" has a single authoritative source, and it can only be answered by a single authoritative source. (NIST in the US, right?) But the question "when should we go to work?" doesn't have a single authoritative source, it all depends, it's all culture, it's all customs, everyone is free to do their own thing, but protestant work ethic bla bla bla, and here we are with most people starting work at 9, and if you don't, you're a weird slacker. Yes, agreeing to start work at 10 in the winter is completely functionally equivalent with moving the clock forward an hour during winter, but it's just mentally impossible to implement because humans are weird like that.
function_seven 8y ago
> So the plan is that instead of people working hours which suit and know about it we agree on a weird collective lie and get everyone to perform the clock-adjusting ritual Well yeah. Much simpler to make the adjustment once, at an agreed upon time of year, than to have a hodgepodge of different companies, schools, retailers, bagel shops, etc. all move their hours independently. In that case you have a first-mover problem and nobody adjusts. It's not a lie anymore than time zones themselves are lies. (i.e. Time zones don't follow strict longitudinal lines, they follow political boundaries instead, and are often wider or narrower than the 15° they "should" be)
- 2038AD 8y ago
  >Well yeah. Much simpler to make the adjustment once, at an agreed upon time of year, than to have a hodgepodge of different companies, schools, retailers, bagel shops, etc. all move their hours independently I'm not sure it is simpler to be honest. It's normal for companies to have different starting hours. I'm just about to move to a job where my official start is half an hour later. That increases to an hour with the actual time time I currently get into work. Even without that, daylight savings is hodgepodge with different countries starting at different times. Ironically anti-daylight-savings people would be welcoming the current news as good when it will likely just mean more countries having daylight savings but not being consistent. >It's not a lie anymore than time zones themselves are lies I can't really disagree.

mhenr18 8y ago

Daylight saving time doesn't apply to the winter though. Winter time is standard time, and DST is in effect during the summer months to better make use of the extra light available during summer by winding clocks an hour forward. The idea being that you get an extra hour of sun in the afternoon.

henrikschroder 8y ago
Yes, sorry, moving back to standard time provides a boost in winter. Both clock adjustments provide different benefits, which is why we do both, to get both benefits. Abolishing DST means you pick one of the two.
zaarn 8y ago
The idea was actually to save power by extending the part of the day that had sunlight.

pmontra 8y ago

I agree. I see why countries in northern Europe have little use for daylight savings: they have darkness in the morning in winter and sun well before everybody's awake in summer whenever they use daylight savings or not. In southern Europe it's different (I live there), especially because those countries tend to center their day not around noon but to later hours: lunch starting between 13:00/15:00 and dinner between 21:00/23:00. Spain basically lives with a double summer time. Italy has a gradient between North (earlier, 1 PM) and South (later). I don't live particularly in the south but if I have to choose I'll pick summer time for all the year, and maybe double of it. Sun at 6 AM is wasted, darkness at 7 PM is depressing. We could end up with two horizontal time zones. UTC+1 in the north and UTC+2 in the south. By the way, the few people from my country that voted in that poll were keen about keeping daylight savings.

LoSboccacc 8y ago
Same for me, if they drop the dst I hope they keep the summer time in Italy, because extended light at evenings is awesome and more useful than extended light when I'm sitting in the office early in the morning
- bonzini 8y ago
  But darkness at 8.30AM is also depressing. For some countries, certainly not all of them, daylight savings time is a blessing and well worth the hassle. Those countries would probably benefit from using standard time and moving everything thirty minutes earlier (effectively a 30 minute off time zone), but it's hard to implement such a sweeping change.
  - LoSboccacc 8y ago
    but here's the thing, in winter I still have to go to work in the dark
    - bonzini 8y ago
      What time do you leave home in the winter? Both me and my wife leave at 8:15 AM, and it's already light in Milan.

dragonwriter 8y ago

> In California, daylight savings actually makes sense, it's a noticeable boost of daylight for your office commute in the winter. Winter is in standard time, so DST has no effect on it. (Also, the standard time evening commute in CA is in darkness, and wouldn't be if it was in DST, so even if you are comparing the status quo against permanent DST rather than permanent standard time, that's still wrong.) DST—“Summer Time”—maximizes post-9-5-working-hours daylight time (to promote shopping and other commercial and recreational activity) in summer, not commute-convenient daylight time in winter.

flurdy 8y ago

Seems like they needed a latitude based timezones on top of longtitude timezones... A grid based timezone system. Sounds like it would pay for a lot of developers careers... And a nightmare. I grew up at 59 degrees north latitude. Daylight savings was pointless. Wintertime I'd go school in the dark (8am) and go home in the twilight (2pm). Lunch time was bright though... My parents grew up at 70 degrees north, where daylight saving is totally useless as there is no daylight in the middle of winter. I now live at 51 degrees latitude and my kids go to school in daylight as school start an hour later here. For a few weeks in the winter daylight saving does make a tiny difference for their morning but not afternoon. But as an adult daylight saving always went the wrong way as it means evenings get darker sooner. I don't care if I commute in the dark in the morning, but I do prefer to do things after school/work in some daylight/twilight.

rudde 8y ago

We have these other seasons in northern Europe, called autumn and spring.