5 ms·

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.

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.