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For 26 Nov 2016:

Consider Tehran with 06:51 sunrise and 16:52 sunset. Another city is Rafsanjan in 850KM southeast of Tehran, sunrise is 6:21 and 16:45 for sunset.

Time zone of two cities is +3.5

Why difference of sunrise is 30 minutes while sunset is 7 minutes?

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    $\begingroup$ As the other answers note, the length of day varies because of latitude (how far north/south you are) and the time of sunrise/set vary due to longitude (how far east/west you are). Those factors combine to give the results above. $\endgroup$ – barrycarter Nov 26 '16 at 16:06
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Tehran (35.7$^\circ$ N) has 23 fewer minutes of daylight than Rafsanjan (30.4$^\circ$ N) on Nov 26 because the Sun is 21$^\circ$ south of the celestial equator and Tehran is 5.3$^\circ$ farther north than Rafsanjan. For the same reason, the north pole has 24-hour night and the south pole has 24-hour daylight at this time of year. On May 26, when the Sun's declination is 21$^\circ$ north, Tehran has 25 more minutes of daylight than Rafsanjan does, and the north pole has 24 more hours of daylight than the south pole does.

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I would have commented but I don't have enough reputation. Sunrise and sunset times may depend on a lot of factors. For example if your city had a big mountain in the west, the sunset would be earlier than what it would have been with the sea instead of the mountain. These things may depends on a lot of factors and you should know the morphology of the zone where the cities are to answer properly. For example there may be mountains in the east of Tehran and that would explain the late sunrise. I don't know the details but I think morphology of the earth is the answer. On a big scale you can say it's a sphere, locally it's everything but smooth.

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    $\begingroup$ Standard sunrise and sunset calculations neglect terrain. $\endgroup$ – Mike G Nov 26 '16 at 15:56
  • $\begingroup$ Really? I mean why is that? Why giving a precise time for sunrise and sunset if it is not accurate? $\endgroup$ – Run like hell Nov 26 '16 at 16:15
  • $\begingroup$ They do account for atmospheric refraction and the apparent width of the solar disk. Accounting for terrain would require computing different times for every hill or valley. $\endgroup$ – Mike G Nov 27 '16 at 1:01
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    $\begingroup$ @MikeG Which is something that people (including me) are trying to do using high resolution digital elevation maps (DEM). $\endgroup$ – barrycarter May 21 '17 at 15:19

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