Yesterday, I explained the elusive “green flash.” I have never seen it; I don’t even know anyone who has. If you have, please drop me a line, I would love to hear about it.
A green flash is not the only optical illusion that can result in a patch of green in the sky. Earlier this month, Sheila Edwards spotted a small green glow in a break in the clouds over Eastern Passage, N.S.
She was curious about what it might be. Judging by the photo, the time of day and the position of the sun, Sheila might have spotted a tiny glimpse of a sundog.
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A sundog, also known as a mock sun, consists of glowing spots around the sun. They are created by sunlight refracting off plate-shaped ice crystals in the cirrus clouds.
Sundogs tend to be most visible when the sun is close to the horizon. The part of a sundog closest to the sun is usually red in colour, while the areas farther away from the sun generally appear blue or green.
Sundogs are more common and easily identified on a clear day. When Sheila snapped her photo, there was a broken layer of low cloud but that doesn’t mean the cirrus cloud with the necessary ice crystals was not present above it.
Thanks for sharing Sheila, and thank you for looking up!
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Cindy Day is the chief meteorologist for SaltWire Network.
