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.
The 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...”
Nacreous 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/t...er-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.
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