Saturday, April 12, 2014

Unexpected teleconnections in noctilucent clouds

Via The Watchers, 11 April 2014

NASA's AIM spacecraft is discovering unexpected "teleconnections" in Earth's atmosphere that link weather and climate across vast distances.

Teleconnection in atmospheric science refers to climate anomalies being related to each other at large distances (typically thousands of kilometers). The most emblematic teleconnection is that linking sea-level pressure at Tahiti and Darwin, Australia, which defines the Southern Oscillation. (1)

Night clouds or noctilucent clouds are tenuous cloud-like phenomena that are the "ragged edge" of a much brighter and pervasive polar cloud layer called polar mesospheric clouds in the upper atmosphere, visible in a deep twilight. They are made of crystals of water ice. Noctilucent roughly means night shining in Latin. They are most commonly observed in the summer months at latitudes between 50° and 70° north and south of the equator. They can only be observed when the Sun is below the horizon. (2)

Video courtesy: Science@NASA

Featured image: Noctilucent clouds over Kuresoo bog, Viljandimaa, Estonia. Author: Martin Koitmäe

1 comment:

Wherami said...

boy are they late to the party :)