This is the season for southern noctilucent clouds. Every year around this time, summertime water vapor billows up into the high atmosphere over Antarctica, providing moisture needed to form icy clouds at the edge of space. Tiny meteoroids seed the clouds, which glow electric-blue as sunlight shines through them.
NASA’s AIM spacecraft is monitoring a 3000-mile wide ring of electric-blue clouds circling high above Antarctica. These are noctilucent clouds (NLCs), made of frosted “meteor smoke” glowing in the mesosphere 83 km above the frozen continent. A four week time-lapse video shows their development since late November:
“The current season began on Nov. 21st,” says Cora Randall, a member of the AIM science team at the University of Colorado’s Laboratory for Atmospheric and Space Physics. “At first, the clouds covered only a small fraction of Antarctica, but now almost all of the continent is blanketed by NLCs.“
And if ground sightings of NLCs over Antarctica are rare. This is only because the population is low. However, the clouds can be seen. Jorgelina Alvarez successfully photographed the clouds over Argentina’s Marabio Base on the Antarctic Peninsula:
Unexpected links between nlc and weather patterns
If you think strange clouds in the atmosphere over remote Antarctica are of little practical interest, think again. Researchers have discovered unexpected teleconnections between noctilucent clouds and weather patterns thousands of miles away.
Would you believe that winter air temperatures in Indianapolis, Indiana, are correlated with NLCs over Antarctica? It’s true. Understanding how these long-distance connections work could improve climate models and weather forecasting.