Enchanting footage of an extremely rare atmospheric phenomenon has been captured in the skies above Finland by Italian photographer and content creator, Rebecca Paviola.
“I was near Lake Inari and I had just woken up,” Paviola told Newsweek. “I opened the door of the room and saw this show in the sky. It looked like a painting!”
Known as mother-of-pearl clouds due to their iridescent rainbow sheen, polar stratospheric clouds are a rare atmospheric phenomenon that form under extremely cold temperatures—below minus 108 degrees F—in the stratosphere, between 49,000 and 82,000 feet above the ground.
Very few clouds form at these heights as there is relatively little moisture there, which is why this phenomenon is so unusual. “I never saw a similar show,” Paviola said.
Seasoned storm chaser, Paul Botten, also saw the light display for the first time, in Sommarøy, Norway, over 300 miles away from Lake Inari. “They were so beautiful to see,” he told Newsweek.
During a typical Arctic winter, polar stratospheric clouds appear no more than two or three times. The phenomenon occurs when trace amounts of water in the stratosphere coalesce to form tiny ice crystals, which drift into thin, wispy clouds. The diffraction and interference of light by these crystals is what produces the ethereal, iridescent sheen.
The colors are most visible at sunrise and sunset, when the clouds beneath have gone gray. Paviola said that the light show was visible for about two hours during sunrise where she was staying in Finland.
However, while these clouds are undoubtedly beautiful, the U.S. Environmental Protection Agency has warned that they can contribute to the breakdown of the Earth’s ozone layer.
The ice crystals that make up these clouds provide a surface upon which chlorine in the stratosphere can be converted to highly reactive compounds like chlorine monoxide. When combined with ultraviolet light from the sun, these compounds can destroy the important layer of ozone that surrounds our planet and protects us from dangerous radiation from the sun.
Usually, nitrogen-based compounds in the sky help regulate the destructive impact of chlorine on the ozone layer. However, these compounds can become tied up in the ice crystals that make up the polar stratospheric clouds, inhibiting their protective effects on the ozone layer.
The ozone layer has been steadily recovering since the 1987 Montreal protocol to phase out the use of chlorofluorocarbons, which produce similar reactions with the ozone layer. However, the World Economic Forum estimates that the ozone may not be fully repaired until 2050.
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