Coronas and Iridescence in Mountain Wave Clouds Over Northeastern Colorado

Coronas and Iridescence in Mountain Wave Clouds Over Northeastern Colorado Scattering of sunlight or moonlight by cloud particles can generate colorful optical patterns that are both scientifically and aesthetically interesting. Photographs of corona rings and iridescence are presented to demonstrate how cloud-particle distributions and meteorology combine to produce a wide variety of observed patterns. The photographs of coronas are analyzed using Fraunhofer diffraction theory to determine that these optical displays were generated by cloud particles with mean diameters ranging from 7.6 to 24.3 m. All examples of coronas and iridescence presented in this paper were observed within mountain wave clouds along the steep lee side of the Rocky Mountains over northeastern Colorado. Such clouds, commonly observed both here and on the downstream side of many other prominent mountain ranges, tend to have small cloud particles with narrow particle-size distributions, conditions that lead to relatively frequent and vivid optical displays. The meteorology accompanying at least one-half of the displays presented here suggest that the wave cloud particles consisted of ice, whereas, at least until recently, it has been accepted that spherical liquid cloud droplets are primarily responsible for coronas and iridescence. Microphotographs of particles collected from the interior of similar mountain wave clouds show that such clouds can indeed contain quasi-spherical ice particles with effective diameters less than 25 m, which provide a mechanism for the high-quality optical displays to be generated within wave clouds at high altitudes with temperatures below 36 to 38C. In fact, these quasi-spherical ice particles maybe commonly associated with mountain wave clouds, thus suggesting that this type of ice particle may regularly produce coronas and iridescence. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Bulletin of the American Meteorological Society American Meteorological Society

Coronas and Iridescence in Mountain Wave Clouds Over Northeastern Colorado

Loading next page...
 
/lp/ams/coronas-and-iridescence-in-mountain-wave-clouds-over-northeastern-3qJIGfVYWA
Publisher
American Meteorological Society
Copyright
Copyright © American Meteorological Society
ISSN
1520-0477
D.O.I.
10.1175/BAMS-84-10-1373
Publisher site
See Article on Publisher Site

Abstract

Scattering of sunlight or moonlight by cloud particles can generate colorful optical patterns that are both scientifically and aesthetically interesting. Photographs of corona rings and iridescence are presented to demonstrate how cloud-particle distributions and meteorology combine to produce a wide variety of observed patterns. The photographs of coronas are analyzed using Fraunhofer diffraction theory to determine that these optical displays were generated by cloud particles with mean diameters ranging from 7.6 to 24.3 m. All examples of coronas and iridescence presented in this paper were observed within mountain wave clouds along the steep lee side of the Rocky Mountains over northeastern Colorado. Such clouds, commonly observed both here and on the downstream side of many other prominent mountain ranges, tend to have small cloud particles with narrow particle-size distributions, conditions that lead to relatively frequent and vivid optical displays. The meteorology accompanying at least one-half of the displays presented here suggest that the wave cloud particles consisted of ice, whereas, at least until recently, it has been accepted that spherical liquid cloud droplets are primarily responsible for coronas and iridescence. Microphotographs of particles collected from the interior of similar mountain wave clouds show that such clouds can indeed contain quasi-spherical ice particles with effective diameters less than 25 m, which provide a mechanism for the high-quality optical displays to be generated within wave clouds at high altitudes with temperatures below 36 to 38C. In fact, these quasi-spherical ice particles maybe commonly associated with mountain wave clouds, thus suggesting that this type of ice particle may regularly produce coronas and iridescence.

Journal

Bulletin of the American Meteorological SocietyAmerican Meteorological Society

Published: Oct 26, 2003

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches

$49/month

Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.

$588

$360/year

billed annually
Start Free Trial

14-day Free Trial