Here’s a ray of sunshine for you as we move through December. Sunset times in Minnesota begin to shift ever so slightly later this week.
Even though we’re still a week away from the shortest daylight of the year on the winter solstice, quirks in the earth’s axis and orbit produce later sunset times before the winter solstice.
So why do our sunrise, solar noon, and sunset times shift later before the winter solstice? Here’s a good explanation from timeandate.com:
The length of a solar day, as this duration is called, is not exactly 24 hours long. It varies throughout the year because of the elliptical shape of Earth's orbit and its axial tilt. It is longer than 24 hours around the summer and winter solstices and shorter than 24 hours around the spring (vernal) and fall (autumnal) equinoxes.
On most days, solar noon does not occur at the same time as noon on your watch. Around the solstices, solar noon occurs a few minutes later than the previous day. For example, on December 21, 2020 – the day of the Northern Hemisphere winter solstice – solar noon in New York will be at 11:54 (11:54 am) EST. On January 4, 2021, the day of the latest sunrise, solar noon will take place 7 minutes later, at 12:01 (12:01 pm) EST.
As solar noons increasingly occur later, sunrises and sunsets also steadily occur later each day after the winter solstice. This is why a location's earliest sunset occurs before, and its latest sunrise occurs after the winter solstice.
The sun set at 4:31 p.m. in the Twin Cities Sunday. Today it sets at 4:32 p.m. By Christmas Day sunset time is 4:37 p.m. And by New Year’s eve, it’s 4:41 p.m.
So we gain 10 minutes of evening daylight by the end of December.
That extra evening daylight becomes increasingly noticeable on clear evenings in the next two weeks.
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