Here is my collection of maps showing length of daylight and twilight. They are in no particular order.
Hours of daylight on the winter solstice.
Difference between the hours of daylight on the summer solstice and the winter solstice.
Summer solstice sunset (local time).
Date of earliest sunrise and latest sunset in summer 2016.
Date of earliest sunset and latest sunrise in winter 2015-2016.
Hours of daylight plus civil twilight on the summer solstice.
Average length of daylight plus civil twilight for all days of the year. Same as Fig. 6 and Fig 7 but an Alaska-centered perspective.
Average length of daylight for all days of the year.
Average annual hours of 1) daylight and 2) daylight plus civil twilight by latitude in the northern hemisphere.
Number of days per year wit 24 hours of daylight.
Hours of daylight on the summer solstice. Northern Hemisphere perspective.