Ukrainian polar explorers show mother-of-pearl clouds in Antarctica and tell about their uniqueness
Polar explorers of the 30th Antarctic expedition managed to see a beautiful and rare phenomenon - mother-of-pearl clouds. Such clouds appear several times a year and mainly in winter. This was reported by the National Antarctic Science Center.
What is the uniqueness of these clouds
- They are stratospheric. Unlike most clouds that live in the "wet" troposphere - the lower layer of the atmosphere, these are formed in the next layer - the "dry" stratosphere.
- They consist of ice crystals and are very thin. Therefore, during the day, against the background of scattered light, they are almost invisible. But when the sun drops a few degrees below the horizon, the light is reflected from the crystals in such a way that an optical effect of iridescence occurs. Thanks to this, a rich play of colors appears on the clouds.
"The emergence of mother-of-pearl clouds is associated with mountain waves: when the air flow in the troposphere encounters a high mountain range, "goes" up, goes around it and "falls" down. This is how a wave is formed," the report says.
Since in the polar regions the height of the troposphere is no more than 7-8 km, the top of the wave enters the stratosphere. There, under the influence of very low temperatures (-50°C and below), moisture quickly turns into ice crystals.
Also, the formation of these clouds can be associated with strong tropospheric cyclones. Mostly nacreous clouds "live" in the polar regions.
As a reminder, Ukrainian scientists took a biopsy from killer whales in Antarctica for the second time in history.