– I have never seen anything like it before, says Raymond Iversen. It was on Saturday afternoon that the man from Klæbu outside Trondheim first discovered the special light phenomenon in the sky. – I was going out to have a smoke, and noticed that there was glitter everywhere in the air and there were pillars of light around me, describes Iversen. It was a spectacular sight outside Raymond Iversen’s living room window. Photo: Raymond Iversen But even if he had never seen anything like this before, he and others have been served this “light show” in the sky several times in recent days. Both in Trøndelag and further south, in places such as Hokksund and Gol, there have been reports of the spectacular sight. – The columns reflect existing light, such as street lights, outside lights on houses and car lights, and the columns have the same color as the light they reflect. It is very special, says Klæbyggen Iversen. Adresseavisen has also mentioned the light phenomenon that has occurred over Trondheim in recent days. There have been several cases of light poles over Trondheim and the surrounding area in recent days. Photo: Raymond Iversen Chase the family out of bed The phenomenon is called pillars of light, and although Raymond Iversen describes it as if the pillars are falling from the sky, it is actually light from the ground which is apparently shot up. Or, to be completely precise, light from the ground is reflected in ice crystals in the air, explains on-duty meteorologist Magnus Ovhed at the Meteorological Institute. – Just as light can be reflected in raindrops and, for example, create rainbows, you can get a similar phenomenon from ice crystals, he says. For Gunnhild Wigtil at Tiller in Trondheim, the light phenomenon created a magical morning when she got up around 06.30 Tuesday. – I thought “Oi! There are pillars of light like that!” I’ve heard about it before, but never seen it, she says. She was quick to chase the rest of the family out of bed, so that they could see it too. – It’s a bit of fun to bring along. He, at fourteen, was quite impressed, but she, at eight, thought it was super cool. She is very fascinated by the northern lights and things like that, so it was really exciting for her. Gunnhild Wigtil and her family started the day with this view. Photo: Gunnhild Wigtil Cold and humidity Meteorologist Magnus Ovhed explains that pillars of light are a so-called halo phenomenon, which is the general term for things that can happen in the sky when light meets ice crystals. – There are probably 30-40 different forms of the halo phenomenon, and how it looks depends on the shape of the ice crystals and their orientation in relation to you, he says. The most common halo phenomenon is when a ring appears around the sun – because it can occur in the same way as the ice crystal looks. – But the more unusual the ice crystal, the more exotic the halo phenomenon can become. A ring around the sun is the most common halo phenomenon. Photo: Karoline Årrestad In order to form pillars of light, the ice crystals must be slightly flat, says Ovhed. There must also be a whole lot of them in the air and colder than minus 15 degrees, so that frost fog forms. – The fog can be very thin, so it is not certain that you experience it as fog, but rather as a faint haze in the air. But there are many ice crystals there, and it is when light meets the frost fog that the phenomenon occurs. Raymond Iversen describes the phenomenon as if sparkling columns of light fall from the sky. Photo: Raymond Iversen The meteorologist also points out that there must be some moisture in the air for frost fog to form. – Usually when it’s this cold, there isn’t that much moisture and ice crystals in the air, but if you have something that can feed the air with moisture and ice crystals, you get this fog, says Ovhed. – Open water and rivers can do this, but you can also get it through, for example, ski resorts that use snow cannons. After all, they do nothing but make and throw out ice crystals. Practical in traffic Klæbyggen Kai Andreas Sørum Øgaard says that he has actually often seen light pillars at the Vassfjellet ski center in Klæbu. He has also seen the phenomenon several times at his home, and most of the times it has been colder than minus 20. – I think it is stylish and fascinating. It is also practical that you get a warning that you will meet a car around the next bend, as you can see the light column up in the air well in advance, says Øgaard. And it is precisely this that is quite amusing about light pillars, says meteorologist Magnus Ovhed. – The halo phenomenon is usually thought to occur in relation to sunlight, but the pillars of light are such a strong phenomenon that they can mostly appear over all light sources. So you can see a lot of light above every single street light, house light and not least car lights.
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