Earliest sunrise location (by local time)

I’ve just gotten a piece of software called “flux” which changes the screen brightness and warmth over time, corresponding with the sun. However, my intent is to use it to help with the winter blahs, so I need to trick it into thinking the sun is rising earlier.

The only setting it seems to have is location, and it used the computer’s local clock. So I need to know the places in the world that has the earliest sunrise location relative to local time. A list of locations in order would be even better.

Can anyone help?

There is no specific answer to this, because the answer will change slightly every single day, and will change drastically over the weeks and months.

On a simple level, it is easy to say that within a single time zone, locations to the east will have an early sunrise, while those in the west will have a late sunrise. But that ignores the fact that that in the summer, locations in the north will be extremely early, while those in the south will be only moderately early. And in the winter, sunrise will be extremely late in the north, while it will be only moderately late in the south.

To confuse things further, the above paragraph is speaking only of areas north of the equator. If you add the southern hemisphere to the mix, it complicates it even further. (At the equator itself, sunrise varies by only a half hour all year long.) [Hmmm… Actually, this paragraph is true of both the northern and southern hemispheres; the complication is that “summer” and “winter” occur in different parts of the year.]

Here are two simple examples: Boston and Miami are both in the Eastern time zone, but Boston is to the northeast, and Miami to the southwest. (In order to better demonstrate these concepts, I have omitted any adjustment for Daylight Time in the below.)

Jan 1: Boston 7:13, Miami 7:07
Feb 1: Boston 6:59, Miami 7:05
Mar 1: Boston 6:20, Miami 6:45
Apr 1: Boston 5:28, Miami 6:13
May 1: Boston 4:41, Miami 5:45
Jun 1: Boston 4:09, Miami 5:30

What you see from these times is that in Boston, the times vary by almost three hours, because it is in the north, where it gets very extreme ----- Think about the north pole! And in Miami, for the same period, it varies by little more than an hour and a half, because the equatorial regions lack the extremes found at the poles.

In the spring (and fall), the above don’t apply, and all points on a north-south line will have sunrise at the same time. But those in the east will have it first, and those in the west will have it later. This accounts for most of the 45-minute disparity on April 1.

Your best solution might be to use your actual location, and to set your clock to a different time than the actual time. That way, all year long, it will think that the time is a fixed amount earlier than actual.

Or try this: Use your actual time, but set the location to a place directly east of where you are. Then it will calculate sunrise there to be a fixed amount of time before sunrise in your area. You may ask, “How far east should I look?” To answer that, look at a time zone map, and realize that each time zone is about one hour wide. So if you want a place that is three hours early, look three zones to the east.

No, that’s the problem. Since it assumes my clock is set in local time for whatever timezone I pick, picking an earlier timezone doesn’t change anything. Sure, the sun is rising at 5:00 my time in the Bahamas, but it’s still rising at 7:00 local time.

And changing your system wide clock can cause a lot of problems. For example, you go to a bank website that only keeps you logged in for a short period of time. Since your local clock is ahead, it thinks that time has already passed and won’t let you stay logged in at all.

Though you did give me an idea. If I set my system-wide time and system-wide timezone, it would be doable. But then the clock in the corner, which I use all the time, will be wrong. Is that worth it?

This be so much easier if I could find a program that would interrupt a program’s call for the system time, and automatically add or subtract a certain amount of time. But people seem to have an ethical problem with creating one, as it would surely be used to get around shareware restrictions.

I’ve used that program and I think it is very optimistic to think your screen will be bright enough to help you. One could say if you actually have hope it will - then you don’t have SAD :slight_smile:

I know it costs money, but you’d probably be much better off using a SAD lamp or just not using flux during the morning.

To me flux is much more useful in the evening to prevent suppression of melatonin that could occur with even small amounts of light. I don’t think the reverse is the case.

Do you need this to work year-round, or only in winter? If only in winter, select a city farther south than yours, and far to the east of its time zone, and the Sun will rise earlier in the winter. It will rise later in the summer, but maybe that doesn’t matter as much to you.

If it’s important that it works year-round, then we’d need to know your latitude, at least, because you will need a city with a similar latitude.

Yeah, winter is all I really care about. Any ideas for such a place?

And I know it won’t help with SAD itself. I should have been more clear. I already have a sun lamp over here. But I want flow to be at least somewhat synchronized with it. Having a bright light shining in your eyes and a dim screen don’t go together.

If you’re in the Central Time Zone in the U.S., the place your computer may recognize with the earliest sunrise on this day is the Galapagos Islands., at 6:08 a.m. Compare that with U.S. sunrises of 6:46 in Pennscola, FL; 6:51 in Birmingham, AL; 6:59 in Nashville; 7:17 in Houston; 7:48 in Minneapolis; or 7:54 in Dodge City, KS.

Maybe the author of the software will fix it to provide flexible configuration of dawn and dusk ?

If you go to this Wikipedia Time Zone map, you can look for places to the East of their time zone, relative to where the straight red lines would be, and to the South of you. You’ll have to decide how much farther south you want to go.

Most time zones seems to be distorted to the West, rather than to the East. If you have a selection you can pick in Costa Rica, that’s near the Eastern default boundary, and south of the US.

This is not a direct answer to the OP question but it is some fun trivia. From Cadillac Mountain

In the Northern winter, is it an option to set it for a city in Australia or something?

So are you trying to set it to use actual local solar time, rather than timezone time? Is there an option for putting in your latitude and longitude?

The sun is rising at 4:15 am local time in King Edward Point tomorrow, if that helps.


Not quite what I wanted, since I’m shooting for closer to 5:00, but that does give me a place to start!

And just in case you wonder why I don’t just turn it off–try it. Everything looks very, very blue when you do that. You need the change to be gradual. I didn’t even notice it yesterday, for example. If only I could not notice the dimming. (I reset it back to my actual location for sunset.)