Sunrise, Sunset, and Twilight! What are your city's times for today? (northwest, 2014)

[EricS39]

Originally Posted by Hiromant

Sunrise: 6:15
Sunset: 18:42

Day length: 12 h 27 min
Highest sun angle: 32°

You are right in Talinn

If you weren't I would still figure it out

[Hiromant]

I'm a bit outside Tallinn but I mostly use its data because the difference is negligible. Timeanddate.com only has bigger cities anyway.

[EricS39]

Originally Posted by Hiromant

I'm a bit outside Tallinn but I mostly use its data because the difference is negligible. Timeanddate.com only has bigger cities anyway.

If you tell me the name of your actual town, or how many miles from Talinn and in which direction.... Or gps coordinates

You pick

I can tell you what your actual sunrise/sunset will be

Moreover, I can give you my own theoretical estimate on when it will be pitched black


When it "appears" pitched black is not the same as Civil Twilight (6 degrees under), Nautical twilight (6-12 degrees under), nor Astronomical twilight (12-18
Under)

I have developed my own assessment on when the appearance of it being pitched black on all edges of the night sky, is achieved

Here's my findings

Under perfectly clear sunny cloudless conditions with perfect visibility, pitched black sky all around that you can confirm visually by looking up (full sky view, no interference from street lights) ....
Happens at 12 degrees below horizon

This makes sense because this follows nautical twilight as being where naval ships on clear seas cannot distinguish the horizon to navigate compass directions

When it is cloudier out, the pitched black visual depiction occurs somewhere in between the 6 and 12 degrees below horizon

At the end of Civil Twilight (6 below horizon), it is insufficient solar lighting to work outside without street lighting, but it is definitely not pitched black at this stage

I stood outside my apartment and made my assessments by knowing the solar elevation angle and waiting till my eyes confirmed no corner of the sky was brighter than any other. This is what I call the moment of pitched black. In overcast weather, my standard is a bit subjective.
If the western sky is blocked with gray fog, it may be even lighting all edges of the sky. Then I go by how dark is dark enough?

By my standards, if you live in Northern Ireland, Scotland, Northern Germany, Northern Netherlands, Northern Poland, Lithuania, Moscow, anywhere north part of Saskatchewan and Alberta, and Ketchikan, Alaska....then under a clear sky, in June....you can Always see the solar glare of the sun, even at the darkest time of the day...by looking North.
(In June it may not appear the solar glare is rotating clockwise...more like solar glare fades from the northwest but the piece to the north won't fade...then in the wee hours of morning, new glare starts forming towards the Northeast.

[Mac15]

I never stay up late enough.

But i'm going to america this summer so before I go I will stay up late and take some pictures. I'm going just after solstice.

[Mac15]

Picture taken at 8:10pm
Looking to the North-West

[EricS39]

It really makes little difference if you miss the solstice exactly. The solstice conditions, length of days, and UV rays associated with it all ...are fairly consistent from early June all the way into third week of July. Whether the sun is exactly 23.44 degrees north or 20 degrees north is a small slice of the pie.

There's a strange catch to this. People think they are smart when they know June 21st sun is the strongest UV for northern hemisphere. This is correct, but early August and late April sun is hardly much different.

If you scale December sun to be 0 and June sun to be 10 on scale of 0 to 10

End of April is already an 8 out of 10, as is end of August. Where equinoxes are 5.

This is because the relationship of season shift from Equinox to solstice is not uniform....it's a sine relationship

Really when you think about it ....May 21st thru July 21st is essentially summer UV and summer daylight with little variation


Land Temperature shifts usually lag behind sun exposure by up to 6 weeks, making April much colder than August, even on days with equal length of day.

Ocean surface temperatures lag even farther behind sun exposure hours, causing North Atlantic hurricane season to run June thru November, San Francisco to get its warmest month in yet September, and New England and Newfoundland to get extremely late spring foliage relative to latitude, but more comfortable post-summer seasons ...this due to ocean effects on land mass.

UV exposure is mostly a product of sun angle though, so don't let April fool you if it feels cold out. Temperature still is a small component of UV though so August still more UV than April, but not by much

An unusually warm day in New York one April day caused my brother, brown hair and tan skin, to get a major red sunburn almost to a blister

One more paradox


What is more UV .....a sunny October day in North Africa? Or a Sunny late April day in Northern UK?

Answer is Northern UK April is more sun. Even if you find the 2 latitudes that have the same sun angle at solar noon, which maxes out at 46.88. (23.44x2) for December 21 vs June 21
In other words latitude 20 winter the same as latitude 66.88 above the arctic circle summer ....

The summer equivalent STILL has more sun...it has the longer duration of day, slower dip of sun in the afternoon...and so summer is much stronger than winter as far as sun ...even more than extremes in latitude differences may seem.
Summer sun is nothing you can easily escape...

If you can get a sunburn in the Carribbean in February, then Stockholm is not close enough to being far enough north for you to be safe in summer

[Bottletree]

Originally Posted by Mac15

I never stay up late enough.

But i'm going to america this summer so before I go I will stay up late and take some pictures. I'm going just after solstice.

You do know what to do to avoid jet lag right? I try to slowly adjust my sleep schedule to fit local time for a few days before leaving.

[Mac15]

Yea thats what I mean. But its going west so it won't be bad plus we will not arrive at our villa to about 10pm.

[EricS39]

Originally Posted by Mac15

Yea thats what I mean. But its going west so it won't be bad plus we will not arrive at our villa to about 10pm.

Mac15, Monday night you will see pitched black sky starting at 19:45

Sunset 18:49 for you Monday

[Mac15]

Nope. Today it was after 8.