Skip to main content
Select Source:

noctilucent clouds

noctilucent clouds (luminous night clouds) Type of clouds, occurring at 80–85 km altitude, near the upper limit of the stratosphere, characterized by a blue to yellow hue, and similar in appearance to cirrostratus. The clouds are seen on summer nights at latitudes between about 50° and 65° in both northern and southern hemispheres; they move rapidly, at speeds up to 300 knots, often in a wave formation.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"noctilucent clouds." A Dictionary of Earth Sciences. . Encyclopedia.com. 17 Dec. 2017 <http://www.encyclopedia.com>.

"noctilucent clouds." A Dictionary of Earth Sciences. . Encyclopedia.com. (December 17, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/noctilucent-clouds

"noctilucent clouds." A Dictionary of Earth Sciences. . Retrieved December 17, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/noctilucent-clouds

noctilucent clouds

noctilucent clouds(luminous night clouds) Clouds, occurring at 80–85 km altitude, near the upper limit of the stratosphere, which are blue to yellow in colour and similar in appearance to cirrostratus. The clouds are seen on summer nights at latitudes between about 50° and 65° in both hemispheres; they move rapidly, at speeds up to 300 knots (556 km/h), often in a wave formation.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"noctilucent clouds." A Dictionary of Ecology. . Encyclopedia.com. 17 Dec. 2017 <http://www.encyclopedia.com>.

"noctilucent clouds." A Dictionary of Ecology. . Encyclopedia.com. (December 17, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/noctilucent-clouds-0

"noctilucent clouds." A Dictionary of Ecology. . Retrieved December 17, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/noctilucent-clouds-0