how Portland has a sunrise earlier than Los Angeles if Portland is further north west and sun rises from the east.

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For example, Los Angeles sunrise is 6:01AM and sunset at 7:57PM. But Portland who is further northwest, has a sunrise at 5:50AM and sunset at 8:44PM.

Why is this???

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Anonymous 0 Comments

In the summer, days in the northern hemisphere grow longer. The further north you go, the longer the days. On the north pole, the sun never sets in the middle of summer.

Portland is further north than LA, so its summer days are longer, meaning it gets an earlier sunrise and later sunset. This more than compensates for the fact that Portland is further west and thus lags behind LA in terms of its true solar time.

Note that the sun in Portland only rises about 10 minutes earlier than in LA, but sets about 45 minutes later. Here you can see the combined effects of its being further north and further west. If it was only further north, then the sun would rise like 25 minutes earlier in Portland and set 25 minutes later. But since it’s also further west, you get about a 15-minute lag on top, which pushes both the sunrise and sunset to be 15 minutes later in Portland. The differences in sunrise and sunset times are the sum of these two effects.

In winter, this is reversed. The sun will rise later in Portland, and despite its being further west, will also set earlier, not later.

As a final tidbit: the time of year when day and night are the same length is called the *equinox*. This happens once in spring, around March 20, and once in autumn, around September 23. You’ll find that on those days, Portland simply lags behind LA, with both sunrise and sunset being later.

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