howmuchsun

Daylight hours in Mariehamn

Mariehamn gets 18h 51m of daylight on its longest day in June, and 5h 54m on its shortest in December — a difference of 12h 57m across the year.

How fast the days change

Around 17 March, Mariehamn gains or loses about 5.5 minutes of daylight every day.

That is quick enough to notice week to week, which is why spring seems to arrive all at once this far from the equator.

Sunrise and sunset by month

On the 15th of each month, in Europe/Mariehamn local time, daylight saving included.

MonthSunriseSunsetDaylightSolar noon
January 09:28 16:10 6h 42m 12:49
February 08:18 17:30 9h 12m 12:54
March 06:56 18:41 11h 45m 12:49
April 06:23 20:57 14h 35m 13:40
May 05:01 22:11 17h 10m 13:36
June 04:15 23:06 18h 51m 13:40
July 04:43 22:49 18h 06m 13:46
August 05:54 21:35 15h 41m 13:44
September 07:08 20:02 12h 55m 13:35
October 08:19 18:32 10h 12m 13:26
November 08:38 16:10 7h 32m 12:24
December 09:38 15:32 5h 54m 12:35

Solstices and equinoxes

DateSunriseSunsetDaylight
March equinox 20 Mar 06:41 18:53 12h 12m
June solstice 21 Jun 04:14 23:09 18h 54m
September equinox 22 Sep 07:24 19:41 12h 17m
December solstice 21 Dec 09:43 15:33 5h 50m

The equinoxes give almost exactly twelve hours of daylight everywhere on earth — "almost" because sunrise is defined by the sun's upper edge rather than its centre, and the atmosphere bends its light over the horizon before it has really arrived. Both lengthen the day by a few minutes.

Assumptions

  • Sea-level horizon. Hills, mountains and buildings all delay sunrise and bring sunset forward, sometimes by a lot in a valley.
  • Standard refraction. Sunrise is taken at −0.833°, allowing for the sun's disc and average atmospheric bending. Unusual air conditions shift it by a minute or two.
  • Local clock time, with daylight saving applied from the IANA timezone database.

Full methodology, sources and known limitations