The southern noctilucent clouds (NLCs) season is over now, but looking back over the entire season reveals something unexpected.
In an 8-year plot of the Antarctic noctilucent cloud frequencies, the 2014/15 season is clearly different from the rest, SpaceWeather reports.
"This past season was not like the others," notes Cora Randall, a member of the AIM science team and the chair of the Department of Atmospheric and Oceanic Sciences at the University of Colorado.
"The clouds were much more variable, and there was an enormous decrease in cloud frequency 15 to 25 days after the summer solstice. That's when the clouds are usually most abundant."
