Mystical cloud seen on video looks like aerial volcano. Here’s what’s really going on
.png "An iridescent cloud can be seen in the sky near Mount Budo, Narathiwat Province, Thailand, according to Twitter user Reg Saddler.")
In what looks like a burst of color from an aerial volcano, a video posted on Twitter instead captured a rare moment when tiny water droplets or ice crystals in the atmosphere scatter the sun’s light, creating a rainbow effect in the sky.
Scientists call the spectacle “rainbow clouds” or “iridescent clouds.”
The video, credited to Orawan Thongchinda and shared on social media, noted the phenomenon wowed onlookers near Mount Budo in the Narathiwat Province in Thailand.
The colorful display typically occurs in altocumulus, cirrocumulus, lenticular and cirrus clouds, and often accompanies thunderstorms, similar to the more common arched rainbows we see that appear to touch the ground.
The view was poetic for meteorologist Michael Ventrice, former operations scientist with Weather Service International, who reposted the video on Twitter.
“When a thunderstorm cloud becomes biblical,” Ventrice wrote.
Atmospheric phenomena expert Les Cowley said these types of clouds often appear late in the afternoon or otherwise on hot and humid days, when conditions are ripe for the types of clouds these rainbows spring from, according to National Geographic.
“What happens is that the cumulus cloud, boiling upwards, pushes the air layers above it higher and higher,” Cowley said. “As the air gets pushed upwards, it expands and cools. And sometimes moisture in that air suddenly condenses into tiny droplets to form a cap cloud,” known as a “pileus.”
It’s this cap cloud — also referred to as “accessory clouds” because they look like hoods sitting atop the upper parts of bigger clouds — that’s responsible for the sky’s colorful performance.
“The droplets in the cap cloud scatter sunlight to form the gorgeous colors,” he added, but “not all pileus caps show iridescence. I usually get images of them from Florida, Southeast Asia and equatorial Africa.”
The scene is so rare because it requires clouds that are thin and contain lots of water droplets or ice crystals of similar size, the National Oceanic and Atmospheric Administration says.
This story was originally published July 15, 2021 at 12:58 PM with the headline "Mystical cloud seen on video looks like aerial volcano. Here’s what’s really going on."
