The winter solstice is the shortest day and longest night in the northern hemisphere. During the summer solstice, the opposite is true, with the day at its longest.
Today, Wednesday, is the winter shutdown. During the winter solstice, the sun shines directly overhead in the southern Tropic of Capricorn, while in the northern hemisphere the day is at its shortest. In Oulu, the sun rose at 10.33 am. Sunset is at 13.58, so the day is 3 hours 25 minutes long. Further south, the day is longer and in Ylivieska, for example, the day is more than half an hour longer today than in Oulu.
In Helsinki, the day is just under six hours long, in Jyväskylä five hours and in Rovaniemi just over two hours. North of the Arctic Circle, the day will not rise at all.
On the Oulu horizon, day length will remain the same until Christmas Eve, after which the day will start to lengthen towards midsummer.
The length of the day varies slightly depending on the calculation formula used to define it. The refraction of light in the atmosphere also affects how we see the sun. Because of the refraction of light, the sun appears to be higher than it actually would be if the atmosphere were not changing the path of the light.
*The subject can be discussed until Thursday, December 22 at 11 p.m.*
*Follow what’s happening near you.* *Read**more news from North Ostrobothnia.*