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Name: Angel W.
Status: educator
Age: 30s
Location: N/A
Country: N/A
Date: 12/7/2004


Question:
Why does sunrise always looks so much different than the sunset?


Replies:
I am not sure they do look different everywhere.

But one definite difference is:

- at sunset, your area has been warming all day
- at sunrise, your area has been cooling all night.

If you are on a coast with prevailing wind from the water, I suppose the cooler morning is more likely to be dulled by fog or clouds.

Do not forget that your personal impression of the appearance of the scene might depend a bit on whether you are experiencing warm or cold.

I think the top of the atmosphere swells upwards during the day and then subsides again each night, because at night the sun has stopped sizzling our beloved ozone and ionosphere with UV and solar particles.

On quiet nights perhaps there is a little less wind and turbulence near the ground, kicking up new dust.

Either of these might make it easier to see dark or deep blue night sky with stars on one side of you, and sunrise lighter blue sky on the other, at the same time. In comparison I tend to think the sunset sky leans towards whitish overhead and reddish horizon; if true that means more light-scattering and absorption is happening at sunset, and we can start to search for the proper reasons why.

I just realized: I am on the West coast. For me, sunrise is always over land, sunset over sea. Consider your own geography. It is likely to make some differences.

Jim Swenson



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