Blue Clouds Over Antarctica: Noctilucent Clouds Sighted Earlier Than Usual In 2016

Lorenzo Tanos

The appearance of blue clouds over Antarctica came substantially earlier this year, and had, in fact, tied for the earliest time noctilucent clouds were spotted over the South Pole since NASA first started tracking data on the clouds.

Noctilucent clouds, or night-shining clouds, usually appear in late November or early December. According to NPR, these are wispy clouds that shine a bluish-white light when viewed from the ground but appear in a far more intense shade of blue when viewed from space. About a decade ago, NASA had launched a satellite that is capable of snapping photos of the ice crystals that form these clouds and based on the space agency's data, those blue clouds appeared over Antarctica much earlier than usual, with the first sighting this year recorded in mid-November.

Satellite images posted Friday on NASA's website show that noctilucent clouds were first seen over Antarctica on November 17, and the clouds forming between that date and November 28. This is based on the agency's Aeronomy of Ice in the Mesosphere (AIM) spacecraft, which was deployed in 2007 in an effort to determine the ins and outs of this unusual event in the South Pole, and to further understand Earth's mesosphere, which can be found about 50 miles above the surface, separating our atmosphere from outer space.

"Noctilucent clouds are a relatively new phenomenon. They were first seen in 1885,' about two years after the powerful eruption of Krakatoa in Indonesia, which hurled plumes of ash as high as 80 km into Earth's atmosphere."

A third NASA article, published in December 2013, explained that noctilucent clouds, or NLCs, have spread out to other parts of the world, and aren't mainly restricted to polar regions anymore.

"In recent years NLCs have intensified and spread. When noctilucent clouds first appeared in the 19th century, you had to travel to polar regions to see them. Since the turn of the century, however, they have been sighted as close to the equator as Colorado and Utah."

"Winter to summer changes in the Antarctic lower atmosphere sparked a complex series of responses throughout the atmosphere - one of which is an earlier noctilucent cloud season," the publication wrote.

"In the Southern Hemisphere, AIM has observed seasons beginning anywhere from Nov. 17 to Dec. 16."

[Featured Image by NASA/Getty Images]