Lollipop-shaped ice found in clouds

by Sarah Derouin
Tuesday, September 19, 2017

Researchers recently found tiny lollipop-shaped ice crystals over the Atlantic Ocean. Credit: Callan Bentley, 2017.

A sky full of lollipops might sound like a candy-filled dream, but these “treats” aren’t what you might think.

Researchers discovered tiny lollipop-shaped ice crystals, or ice-lollies, during research flights in 2009 and 2016 over the Atlantic Ocean. The crystals — just a millimeter long and found 1 to 2 kilometers up in the sky — form in clouds when a shard of ice, called an ice column, collides with a liquid water droplet. Temperatures in this part of the atmosphere range from minus 3 to minus 8 degrees Celsius, so the products of the collision instantaneously freeze to create a lollipop-shaped crystal.

The presence of ice-lollies may affect the life cycle of clouds, altering the balance of liquid water and ice, and could also impact the formation of precipitation, the team suggested in Geophysical Research Letters.

Ice-lollies haven’t been seen on the ground: Either rising temperatures or falling humidity can destroy the delicate crystal as it falls. But Stavros Keppas, a postgraduate at the University of Manchester in England and lead author of the study, suggested in a statement that ice-lollies might be formed on a regular basis at high latitudes.

© 2008-2021. All rights reserved. Any copying, redistribution or retransmission of any of the contents of this service without the expressed written permission of the American Geosciences Institute is expressly prohibited. Click here for all copyright requests.