Ultra-rare 'rainbow clouds' light up the Arctic Circle like auroras in stunning new photos

Bright multi-colored clouds shining in the night sky above Mount Jökultindur in Iceland on Jan. 25. (Image credit: Jónína Guðrún Óskarsdóttir)

The dark skies in the Arctic Circle recently shone with ethereal multi-colored light. But this jaw-dropping spectacle was not caused by auroras. Instead, the iridescent rainbows were caused by clouds of tiny ice crystals floating higher in the atmosphere than is normally possible.

The clouds, known as polar stratospheric clouds (PSC), only form when the lower stratosphere reaches temperatures below minus 114 degrees Fahrenheit (minus 81 degrees Celsius). Normally, clouds do not form in the stratosphere because it is too dry, but at these extremely low temperatures "widely-spaced water molecules begin to coalesce into tiny ice crystals" that form into clouds, Spaceweather.com reported. This means PSCs can form much higher up than normal clouds, between 9.3 and 15.5 miles (15 to 25 kilometers) above the ground. 

As sunlight shines through these crystal clouds, it gets scattered, creating multiple different wavelengths of light, which has inspired the PSCs nickname, "rainbow clouds."  Due to the extreme altitude of the clouds sunlight can hit the crystals and scatter above an observer even if the sun is beyond the horizon, which is when these clouds appear brightest. 

On Jan. 25, extreme freezing conditions in the stratosphere allowed for a rare outbreak of PSCs across the Arctic Circle, including Iceland, Norway and Finland, according to Spaceweather.com. Amateur photographer Jónína Guðrún Óskarsdóttir captured a stunning shot of the vibrant clouds above the peak of Mount Jökultindur in Iceland and photographer Fredrik Broms took a series of snaps of the colorful lights above Kvaløya near Tromsø in Norway.

Related: Solar storm smashes hole in Earth's magnetosphere, triggering extremely rare pink auroras

PSCs shine through a gap in the clouds above Kvaløya in Norway on Jan. 25. (Image credit: Fredrik Broms / northernlightsphotography.no)

There are two types of PSCs: Type I, which are made from a mix of ice crystals and nitric acid, which produces less spectacular colors and may be linked to the formation of ozone holes; and Type II, which are composed of pure ice crystals and produce more vivid colors. The ones that recently formed over the Arctic were Type II.

Type II PSCs are often referred to as nacreous clouds because their iridescent hues can sometimes resemble nacre, also known as mother of pearl, which is produced in the shells of some mollusks. However, they are much rarer than Type I clouds.

Type II clouds typically occur no more than two or three times a year in the Arctic, normally during the colder winter months, according to Spacewaether.com. However, experts believe that both types of PSCs could occur more often in the future as climate change creates more extreme weather, which could have a knock-on impact on the ozone layer if more Type I clouds can form, according to NASA.

Due to their intense colors, nacreous clouds are often confused with the northern lights, or aurora borealis, in the Arctic. These more common phenomena occur when highly energetic particles emitted by the sun travel down the magnetic field lines of Earth's magnetosphere.  

Harry Baker
Senior Staff Writer

Harry is a U.K.-based senior staff writer at Live Science. He studied marine biology at the University of Exeter before training to become a journalist. He covers a wide range of topics including space exploration, planetary science, space weather, climate change, animal behavior, evolution and paleontology. His feature on the upcoming solar maximum was shortlisted in the "top scoop" category at the National Council for the Training of Journalists (NCTJ) Awards for Excellence in 2023. 

  • Gonzobeatnik
    I saw one of these in Charlotte, NC on the 18th or 19th of December 2023. It was small an isolated but I saw it none the less. I thought it was a sundog or sunsprite but Google told me no. I took a pic with my phone but you can barely see the colors that were visible with the naked eye.

    Pretty sure we're south of Scotland too....that's why I added my comment!
    Reply
  • Hartmann352
    The clouds are composed of pure ice crystals refracting sunlight and form in the upper atmosphere at altitudes between 9.3 and 15.5 miles above Earth's surface.

    PSCs are also known as nacreous clouds: a name inspired by an iridescent material called nacre, or mother-of-pearl, found in the shells of some mollusks, according to LiveScience.

    This usually occurs only a few times each year during winter months, as stratospheric temperatures in the Arctic rarely reach the required threshold of -85 degrees Celsius for polar stratospheric clouds to form. NASA forecast models show temperatures in the polar stratosphere have reached this staggering low.
    https://assets.msn.com/staticsb/statics/latest/views/icons/ArticleImageFullscreen.svghttps://img-s-msn-com.akamaized.net/tenant/amp/entityid/AA1lUMmx.img?w=768&h=402&m=6The stunning display has been seen in the skies over the United Kingdom. By: X/@WalkerScienceND © Knewz
    Photographer Ramunė Šapailaitė captured a stunning image of the rare event in southern Norway, showcasing the photo via Instagram.

    "The colors are spectacular," Šapailaitė told SpaceWeather.com. "The clouds were visible in the sky all day, but the colors really exploded just before sunset."

    The event is typically confined within the Arctic Circle, according to the outlet, but this year's display has extended beyond these bounds with sightings in places like Scotland and Liverpool, England.
    Knewz.com reported on some of these UK sightings with photos captured by a BBC meteorologist.
    “Great shots of recent #NacreousClouds," Tomasz Schafernaker posted on X. "They can be extremely high — three times higher than an airplane at cruising altitude. Nacreous clouds are an indicator of especially cold air high in the atmosphere...”
    https://assets.msn.com/staticsb/statics/latest/views/icons/ArticleImageFullscreen.svghttps://img-s-msn-com.akamaized.net/tenant/amp/entityid/AA1lUMmA.img?w=768&h=402&m=6Nacreous clouds spotted over the United Kingdom. By: X/@iffatshahnaz© Knewz
    United Kingdom Meteorological Office Spokesman Stephen Dixon (via The Guardian) also weighed in, saying, “Nacreous clouds are quite rare in the UK and are very high clouds. They can make good spectacles for viewers as they reflect colored light from the sun, often after sunset and before sunrise.”

    The Met Office issued a warning for high winds across the northern half of the UK on Thursday, December 21. The inclement weather has been credited to an area of low pressure, named Storm Pia, expected to bring winds of up to 80 mph and possible power outages.

    More PSCs are expected to pop up over the next few months, according to SpaceWeather.com.

    See: https://www.msn.com/en-us/weather/topstories/rare-rainbow-cloud-phenomenon-shining-over-arctic-circle-caught-on-camera/ar-AA1lUTSx
    One of these special kinds of rare clouds is known as nacreous clouds. More commonly referred to as "mother-of-pearl clouds" because of their iridescent or rainbow nature, seeing nacreous clouds is incredibly rare in most parts of the world. However, images of these clouds are pretty astounding, which may have led you to wonder what nacreous clouds are and how they are formed.

    See: https://www.slashgear.com/1407468/nacreous-clouds-explained/
    Nacreous clouds form in the lower stratosphere over polar regions when the Sun is just below the horizon. The ice particles that form nacreous clouds are much smaller than those that form more common clouds. These smaller particles scatter light in a different way, which is what creates the distinctive luminescent appearance. Due to their high altitude and the curvature of the Earth’s surface, these clouds are lit up by sunlight from below the horizon and reflect it to the ground, shining brightly well before dawn and after dusk. They are most likely to be viewed when the Sun is between 1º and 6º below the horizon and in places with higher latitudes, such as Scandinavia and northern Canada. For this reason, they are sometimes known as polar stratospheric clouds. Nacreous clouds only form below -78 °C so are most likely to occur during the deep cold of the polar winter.
    Hartmann352
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