ELECTRIC-BLUE CLOUDS SPREADING OVER ANTARCTICA

ELECTRIC-BLUE CLOUDS SPREADING OVER ANTARCTICA

Noctilucent clouds (NLCs) around the south pole are spreading and brightening. The latest preliminary image from NASA's AIM spacecraft shows more than 4 times the coverage of just a few days ago:

The season for southern hemisphere noctilucent clouds (NLCs) began on Nov. 22nd with just a few puffy clouds over the frozen continent. Once NLCs first appear, AIM has shown that they rapidly multiply. Indeed, this is happening now, and much of Antarctica soon could be blanketed in electric blue.
Earlier this year, AIM researchers announced a surprising teleconnection: The apparition of NLCs in the southern hemisphere is linked to cold air temperatures thousands of miles away in the northern hemisphere."For example, we found that the winter air temperature in Indianapolis, Indiana, is well correlated with the frequency of noctilucent clouds over Antarctica," says Cora Randall, AIM science team member and Chair of the Dept. of Atmospheric and Oceanic Sciences at the University of Colorado. Other US cities were similarly correlated.
Data from previous seasons show a 2-week time lag between cold outbreaks in the north and changes to NLCs in the south. However, because the 2014-2015 season is less than two weeks old, the correlation is not yet obvious. "I don't expect the northern hemisphere (NH) teleconnection signal to have significant effects on the onset of the southern hemisphere (SH) season for noctilucent clouds," says Randall. "But once planetary wave activity in the SH stratosphere is quiet (should be soon), then I would expect the connections with the NH winter to become more evident."
Randall and a group of colleagues led by Laura Holt of NorthWest Research Associates have just submitted a paper to the Geophysical Research Letters detailing the link between northern winter and southern NLCs. If you have a GRL subscription, keep an eye out for their article entitled "Summertime polar mesospheric clouds linked to wintertime surface cold air outbreaks."

From SpaceWeather.com