ElI5: Why do different places on the earth receive different annual sunlight hours?

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Just saw a post talking about how Europe gets a decent amount of sunlight less than the Americas. Why would this be? I understand the how latitude changes the time of sunrise/sundown but wouldn’t it average out in the end? For example Alaska vs. Hawaii. Hawaii gets close to 12 hrs of sunlight every single day all year. Alaska might get 22 some days in the summer but 2 in the winter? Wouldn’t both places receive the same annual hours of sunlight or am I missing something?

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Anonymous 0 Comments

If you’re just talking about hours the sun is above the horizon then the high latitudes actually get (very slightly) more sunlight than the tropics. But you really need to consider the angle of the sun for heating, solar power, growing crops, etc.

In the tropics the midday sun can shine vertically down, so a square metre of sunlight heats up a square metre of the earth’s surface. Once you get up to 60° latitude, the same square metre of midday sun is now angled and spreads over 2 square metres of the surface, halving its heating effect. It’s even worse when you consider the even shallower sunlight angles at other times of the day.

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