Diffraction and Other Phenomena Corona around the Moon
Dr. Christopher M. Godfrey Colors appear when particles have uniform size University of North Carolina at Asheville Image ©2004 Mount Washington Observatory
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
Iridescence – Diffraction Glory Different sized droplets distort a corona Pastel colors appear in high, thin clouds
Image © Shannon Story
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
Glory Glory
Image © Jonathan Lansey Image © C. Godfrey
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
1 Glory Brocken Spectre and Glory
Image © Ann Bowker Image © C. Godfrey
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
Other Optical Phenomena Crepuscular Rays
Dust, water droplets, and haze all scatter light from the sun after passing through breaks in the clouds Rays are parallel Perspective makes rays appear to diverge
Rocket Trails Image © Robert Koch
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
Crepuscular Rays Crepuscular Rays
Image © C. Godfrey Image © C. Godfrey
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
2 Crepuscular Rays Anticrepuscular Rays
Convergent at the antisolar point* Extension of crepuscular rays
East West Note scattering of light Antisolar point above the cloud
*Don’t confuse the antisolar point with the anthelic point, Image © C. Godfrey which lies 180° in azimuth away from the Sun ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
Anticrepuscular Rays Anticrepuscular Rays
Image © C. Godfrey Image © C. Godfrey
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
Sun Pillar: A reflection phenomenon Heiligenschein
ATMS 455: Physical Meteorology – Spring 2021 ATMS 455: Physical Meteorology – Spring 2021
3 Heiligenschein
ATMS 455: Physical Meteorology – Spring 2021
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