In the transition tonight from the Ed Show to The Rachel Maddow Show, what we call "the toss," Ed shared a picture with Rachel of what he called a double sun dog. Jump to 4:33 in this video to see it. If you don't have video, that's ok, it looks a lot like the one above except Ed's is from Big Detroit Lake in Minnesota and the one above is from Fargo, but the phenomenon is the same.
I'd never heard of such a thing, but it turns out I am more familiar with them than I realized, as you'll soon see.
The scientific name for those extra spots of light is "parhelion" and NOAA explains that they appear as the result of sunlight refraction though ice crystals in cirrus clouds. Sunlight refracting though moisture in clouds sounds like the definition of a rainbow to me, so I think what we're talking about here is essentially an ice rainbow. (Cirrus clouds are the whispy ones and they're formed when water vapor turns into tiny ice crystals.)
But wait, meet me after the jump for a cool realization...
So I'm looking through parihelion photos online for this very blog post and I come upon this fellow's Parhelion Above Arc de Triomphe photo.
He took his in August, but I understand cirrus clouds always have ice crystals so the season doesn't necessarily matter. The Arc de Triomphe photo is only of the sun dog, with the sun out of frame, and it occurred to me that I'd seen just such a colorful splotch in the sky over New York City just the other day.
I took the photo below from my kitchen window on New Year's Day at about 3:50 p.m. ET. At the time I thought it was the beginnings of a rainbow and I was disappointed when the clouds shifted a little and it just went away. It seems pretty obvious now that in fact, it's a sun dog.
Definitely cirrus clouds. Not a double sun dog like Ed got, but the right color (red on the sun side), height (level with the sun), and placement (I used this compass overlay , aligned the landmarks of the Williamsburg Bridge and the World Trade Center with my kitchen, and eyeballed it as pretty darn close to the 22 degrees it's supposed to be.)
So how 'bout that?
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That explains a lot. At first I thought it had something to do with the sun's weather activity this year, which has been more active than usual. Happy to learn I was definitely wrong, haha. :P
P.S. Of course I'm referring to the single rainbow-y spot in the NYC image, which I have seen a lot of the last few weeks. I've never seen a full double sun dog.
From what I understand, sun dogs are more common near the Great Lakes, where they would throw off old style navigation by the sun.
Note too the darkening within. The same reflection/refraction geometry is responsible for less light transmission within the bow.
From MIT OpenCourseWare (50 minutes), Professor Walter Lewin's lecture on rainbows (a passion of his) is a classic that should be in every geek's bookmark/favorites list. Rainbows, Double/Triple rainbows, fogbows, sun/moondogs, halos and many of their subtleties are described and a "rain"bow is demonstrated within the lecture hall. It is presented with the the math although you do not need to understand that to understand why these occur.
In your photo, there are more things than just the sun dogs. There are additional arcs and glowing items. There is a website dedicated to atmospheric optics which can categorize the various phenomena you've captured. check http://www.atoptics.co.uk/ to see additional examples and to put names to the arcs you've found.
Rainbows appear _opposite— the sun. A rainbow after an evening shower will be in the east. Sundogs appear next to the sun, in the west in the afternoon.
I'd also note that these phenomena should be a lot less remarkable, but too many people never look at the sky.
... also, there can be up to 4 sundogs, at 9, 12, 3 and 6 o'clock.
Sundogs appear at the same altitude as the sun because the flat ice crystals fall through the air column like leaves, flat.
beautiful.
Two pundits reflecting on Barack Obama.
.
When we take flight, the effect is not just on one axis, with a mirage Obama to the right and left. We rise above the haze confined to the surface. His apparition is high and low. These correspond to the pundits on particular issues- they either like or dislike his position on the war on terror, his position on Plan B, his position on the XL pipeline, or his position on religion versus rational atheism.
Eye of Horus. A dot in a circle.
Good references, rarely surpassed:
Even the title of Minnaert's book rings like a wind chime.
I saw this last night too. I have relatives in around the Twin Cities... as well as my best friend who lives in Bemidji. They have said something about this before.
Very cool looking.
There are similarities with this phenomena and rainbows, there are also moon-doggies at night but they are a rainbow circle around the moon under certain atmospheric conditions.
I saw something like this a few days ago. Before the sun rose, there was a very bright vertical shaft of orange sunlight just above where the sun was going to rise. This was an ice pillar. After the sun rose, there were two sun dogs visible, similar to the picture above. What really struck me was that the sun dogs actually appeared to be close, so that I could see background objects like buildings and cars BEHIND the sun dogs. I had never seen anything like that before, as all rainbows and sun dogs I had seen before were always apparently distant. In trying to see why these were so different, I notice that there were very tiny ice crystals, about the size of specks of dust, swirling around outside my window, unlike the drops in rainbows, which are usually quite distant. Once again, just another reason to open your eyes and look at the wonders outside your window whenever you can. You never know what amazing sights may await you.
Awesome ED! That's why we love ya! Um...but what kind of 'tea' did you say you had in that Thermos again??