Where to hate daylight saving time and where to love it

tl;dr version: just scroll down and play with the map.

If you’re on Facebook or Twitter or really are any person in America with friends who say things, you hear it twice a year, in March and November: “LIFE IS THE WORST WHY DO WE HAVE TO CHANGE THE CLOCKS WE SHOULD GET RID OF DAYLIGHT SAVINGS [sic] TIME!!!!!”. Maybe you’re even one of the people saying it.

Usually the whining is short-term shock at the sudden change in the timing of day and night, not a reasoned assessment of what it means for the timing of daylight over the whole year. People often don’t even know what they’re complaining about: they’ll rail against “daylight saving time” even if it’s the early sunsets of standard time that they hate. For the record I’m no DST hater, because my morning commute is about 5 seconds (no pants required) so I never need to wake up before the sun, and I live in a place where the sun sets at 4:11 in the damn afternoon in winter so I’d love to push that back an hour.

There is a cool interactive piece about this by Keith Collins on Quartz charting how keeping or abolishing DST would affect your daylight hours. In New York, you’d have to wake up at 4:30 AM or go to bed absurdly early in order for DST not to increase daylight in your waking hours.

Daylight hours

If you wake up at 6:30 like a normal human (note: “normal” still sucks), DST makes you wake up in darkness for a handful of extra days in spring and fall. The daylight is regained in the evening, of course, but I’ll grant that waking up before the sun is miserable.

It’s noted on that page that the chart’s data “assume you are located in New York, but differences are minimal across the contiguous 48 states,” but I’m a geographer and must always disagree with any and all spatial claims, by anyone. I live in the same time zone where I grew up, but the sunrise/set times are almost an hour different between the two places.

Total daylight is a function of latitude and time of year, as seen in this plot from Wikipedia:


Latitude thus affects how early or late the sun rises and sets, but what the clock says depends on a location’s longitude within its time zone. The farther east it is, the earlier the sun will rise and set. Considering all this, I want to map sunrise and sunset times in the United States and see how they are affected by daylight saving time. I’ve done so by using a little bit of GIS and the super handy SunCalc JavaScript library by Vladimir Agafonkin.

Let’s map how many days of the year have reasonable sunrise and sunset times with and without daylight saving time. I define “reasonable” times as 7 AM and 6 PM. That’s kind of arbitrary, but assuming roughly half an hour of twilight, it at least puts some light in the sky around the time the average American wakes up (6:30ish based on some cursory poking around) and at the end of the business day. But you can define them differently. Explore the coarsely gridded map below and see the geography of sunrise and sunset with and without daylight saving time.

To summarize, these are the scenarios using my preferred times. First, the state of things as they now exist:

Sunrise / sunset with normal DST

And here’s what everyone apparently wants, death to daylight saving time:

Sunrise / sunset with no DST

It looks like an improvement, right? The sunset map doesn’t change a whole lot, while vast areas seem to get a lot more days with morning sun. So yes, maybe you could cut your coffee budget if you live on the western side of your time zone. Just remember you’d be giving up those wonderful summer evenings.

Now let’s go bonkers and implement daylight saving time all year long. Or, for the same effect, we could get rid of it but have everyone shift their time zone one to the east:

Sunrise / sunset with DST all year long

Admittedly the sunrise map looks bleak. But look how much brighter that sunset map gets. I mean, just look at it!

If you want consistent morning daylight, you should be as far southeast in your time zone as possible. I recommend the Big Island of Hawaii. If, like me, you’re all about evening sun, hop the border to the southwest part of the next time zone. But remember that’s for consistency, not total daylight. The farther north you go, the longer days will be in the summer—but the shorter they’ll be in winter.

Anyway, here’s all that in poster form for some reason.

DST maps


  1. Awesome visualization…unfortunately, it is based upon a reversed interpretation of what DST is. DST is the 1 hour forward time we observe during the Summer. The rest of the time is Standard. The effects noted above are reversed.

    29 November 2015 @ 9:09pm

  2. …that is, ending DST would NEVER create an increase in the number of days where the sun rises before 7AM. I can only increase them. If the sun was to rise on a give day at 6:30am standard time…that would be 7:30am DST. DST creates earlier sunrises when in place.

    29 November 2015 @ 9:27pm

  3. This is a crazy idea, but how about setting 6:30am to be the sunrise every day of the year? Then the sunrise is fixed but the sunset is variable. Every day will no longer be 24 hrs, as you will need to wake up a min earlier or later each day of the year (but you won’t notice this). No more drastic changes, no more problem of having to get up when it is dark, and you truly get to maximize daylight every day!!!

    This will obviously present many logistical problems: We would need to throw out all clocks that are not synched to the internet (since we would need to set them daily), we would have to have a different time at basically every point on earth (unless we set the sunrise to be at 6:30 at a certain point within each time zone)

    30 November 2015 @ 12:09am

  4. What happens if DST is reversed with standard time during the summer months and DST in the winter months?

    30 November 2015 @ 7:57pm

  5. Hey all, for anyone interested in petitioning to make DST the new standard time, please sign the official White House petition and pass it around to everyone you know! http://wh.gov/iyQ72

    1 December 2015 @ 9:34am

  6. What would happen if we set the time halfway? Would that not be the best option?

    1 December 2015 @ 2:47pm

  7. This is great. I”d argue that a “reasonable” sunrise time is not before say, 5:30, or 6. So I’d love to see a map with different sunrise values for “reasonable”. One problem with eliminating DST is you get some pre 5-AM sunrises. A 4:50AM sunrise is a bit of a waste of daylight.

    3 December 2015 @ 7:25am

  8. Gotta say, as a night owl, “reasonable” sunrise time shouldn’t be defined as “before 7” – the key is AFTER 5! Standard time gets light too early in the summer, before I often get to bed. You may not want that dark morning, but the sun coming up before I hit bed is FAR worse. I’d be delighted with a DST all year mode.

    3 December 2015 @ 10:00pm

  9. I say lets get rid of it, all it does is make people cranky and throws things off for about a week overtime theres a change! I hate going back and forth! Look at Arizona and Hawaii they’re fine and they don’t do the stupid crazy DST!

    Jacqueline Lewis
    6 December 2015 @ 3:17pm

  10. What happens if you split the difference? Seems to me that would be the best compromise — adjust the clock 30 mins and leave it there.

    9 December 2015 @ 9:15am

  11. Can you add a map that reverses DST? i.e. spring back and fall forward

    10 December 2015 @ 1:12pm

  12. I’m in the OKC metro area and I much rather prefer DST year around. Sunrises don’t matter to me at all. What bugs me is it being dark by the time I get home from work at 5:30. I much prefer still having daylight around 8:30 as it makes the day feel longer even if it really isn’t. It’s easier to get out and do things. I’m able to get just that much more vitamin D since I’m indoors 90% of my day. Overall I would like life a lot better with more daylight hours.

    10 December 2015 @ 1:44pm

  13. What if we were to split the difference, and set all clocks a half-hour ahead?

    10 December 2015 @ 2:13pm

  14. I dont care about sunrise at all, just want to enjoy some daylight after work

    10 December 2015 @ 2:48pm

  15. I suspected DST year round would be awesome, but I had no idea. Can we start next year?

    Kevin S
    10 December 2015 @ 3:55pm

  16. What would happen if DST were reversed?(spring back, fall forward)

    10 December 2015 @ 7:19pm

  17. Hi, I think this would be really great if you could do a few maps for other parts of the globe, particularly Europe, which would be particularly interesting, given the higher latitudes in places such as Scandinavia. Awesome maps.

    11 December 2015 @ 4:59am

  18. I am in favor of DST. Since all I do in the morning M-F is get ready for work, it doesn’t bother me that the sun gets up after I do. The biggest advantage of DST is later, when I come home, I have a few hours of daylight to get things done in the yard in the fall and spring that I can’t do in darkness. Knowing I can sit on my deck for a while and watch Mother Nature in my back yard is also really nice after a hard day. And when it comes to my commute; Driving 25 minutes in the dark going in when I am calm and rested after a good night’s sleep, is far better than going home in the dark after a stressful day. So many people are so stressed at the end of the day and their eyes are tired and they have schedules to keep for the kids and chores; is it better they have more daylight if only to ease the nightmare of rush hour when bright headlights coming at you only makes it worse? I don’t think so.

    DST was created so farmers would have more daylight in the morning to get their crops in and chores morning chores good get done in daylight. It really has become unnecessary now that we use so much electricity to light our darkest hours. But I believe that with DST, less is used in the evening and in either case not much is used in the morning.

    11 December 2015 @ 7:00am

  19. is it better they have more daylight if only to ease the nightmare of rush hour when bright headlights coming at you only makes it worse? My bad, I meant I DO THINK SO.

    11 December 2015 @ 7:02am

  20. Andy makes two implicit assumptions. The first is that you want to align the daylight hours with the time that you are awake. The second assumption is that your body clock aligns to the clock on the wall. If these assumptions were correct, then, by shifting the clock forward an hour in the summer (daylight saving time) a night owl would have a better alignment with the daylight hours and thus be happy. Unfortunately the biological clock does not align with the clock on the wall at all. Shifting the clock an hour forward simply means he has to get up an hour earlier. That is bad for night owls, they want to get up late, not early!

    16 December 2015 @ 2:04pm

  21. Exactly! All DST does is force everyone to get up an hour earlier to get to work or school by 9 am (which is really 8 am). If you’re lucky and live in a place where the clock matches the actual natural solar time. Because unfortunately our bodyclocks follow the sun and not the clock on the wall. So for the 25% of us who are night owls (evening chronotypes), which most teenagers temporarily become btw, what is already an unholy waking-up time becomes an even worse interruption of our natural sleep pattern. With all health and performance issues that come with lack of good sleep…

    16 December 2015 @ 2:26pm

  22. To all the people craving year-round consistency in daylight times: have you considered moving closer to the Equator? Depending on your spot in the world (longitude & latitude) you have a certain number of daylight hours in a day. For most places away from the Equator that number is different in summer and in winter. And winter will always have shorter days and longer nights. There’re no escaping the (cozy) dark days of winter!

    16 December 2015 @ 2:28pm

  23. Animals adapt their activities to daylight… let’s say every day. Should we move our watches dayly or weekly? Impossible. So the best we can do, is switch our watches twice a year. And for practical use: switch the hour on your watches the daterday in the afternoon befor D-day and start immediately to live with “the new hour”: no adaptation problems, neither for kids nor for adults.

    20 December 2015 @ 4:28am

  24. I find it interesting to hear people talk about their body clock following the sun. I am in my 40’s and my body clock is pretty consistent all year long. As long as I go to bed before midnight, I will wake up (without an alarm clock) within the same 30 minute window, whether it’s December or June. I live in Arizona, which does not observe DST, and I actually love it. I have lived in other states (WA and CA), and time shift would muck up my internal clock and I’d have to set an alarm so I wouldn’t be late for work (or I’d get up way too early depending on the shift direction). The whole sunrise/sunset thing doesn’t really bother me, although I can understand why it might others.

    The funny thing to me is that a moment in time is the same regardless if it’s in London or LA. The fact that we use time zones or DST at all is arbitrary. This is why computer systems have to use GMT to data storage to avoid timezone related issues. This further gets complicated if humanity gets around to colonizing other planets (talk about time zones). This is why SciFi series such as Star Wars or Star Trek use the concept of a singular system (i.e. “Stardate” for the latter). So when you think about it, the fact is that the days of the week, months, and time zones, they are all arbitrary.

    Well written article by the way. :-)

    20 December 2015 @ 12:36pm

  25. I always think it’s strange that so many people’s bodies are affected by this one hour change for more than a day or two. What Arizona does makes sense due to the heat and lack cloud cover, but most other places it doesn’t. Adjusting to the common work schedule is simply why we do this. Farmers, like mentioned before, could care less about time.

    What Dan Flynn was about to do in Texas scared the hell out of me. Taking away daylight saving meant less productive hours (AFTER) work. I may live out in the country but that’s just more of a pastime and peaceful place to live. It is not a real income. I still however need to do things after work and depend on this great light from sky. Most active people who work during the day are usually on my side. You don’t need daylight when your getting dressed for work in the morning. And being an early bird working up a sweat before work just isn’t for most people. I would barely have time to start a outside project.

    One of his reason he mentioned was having to manually change clocks. C’mon I can think of a million things worse than that.

    29 December 2015 @ 3:24pm