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Thursday, February 10, 2011

Sun Dogs in Iowa

No, they're not a new breed of dog that you haven't heard of!  Sun dogs are a weather phenomenon.
They are bright patches of white or coloured light that occur on either side of the sun - sometimes only on one side, and sometimes on both sides.  Generally, they're most visible when the sun is low in the sky - either close to sunrise or sunset.  In the picture below, the sun is to the left (obviously) and then just to the right of the church steeple, you'll see a kind of rainbow blob.  That's a sun dog.
Here in Iowa, it can get pretty cold in the winter.  That's when you might see sun dogs.  The reason is that sun dogs are caused by ice crystals that drift in the air.  The crystals can either be randomly distributed through the air, in which case a ring, or a halo, can be seen around the sun.  With sun dogs, the crystals are sinking through the air and becoming vertically aligned, so that the sunlight that passes through the crystals is refracted horizontally.  That results in sun dogs!  Here's a picture of the right hand sun dog without the sun.  I wish the colours were better in these photographs because they really were like vertical stripe rainbows.
This past week was really obnoxiously cold here, and I saw these sun dogs on my way home from work earlier this week.  I snapped a few random shots with my cell phone.  Believe me, I was not looking at my cell phone at the time.  The camera button is on the side and I just held it up in one hand and snapped.  I had no idea if I'd get any good shots, but when I got home and checked, I had a few decent ones, so that's what I've shown you here.
I wish I could have taken a shot showing both sun dogs, but I could only get one side at a time.  Here's the other side...
As the sun went down, the sun dogs grew more faint.
I like looking at the sky and watching clouds and sunsets.  It's not very often that I get to see more unusual phenomena like sun dogs, but when it happens, it's quite exciting.  If you live in a warmer climate, you probably never get to see them.  I hope you enjoyed seeing them vicariously if that is the case!  If you want to see more sun dogs, there are some great pictures online, including this one from Wikipedia, which is actually taken in central Iowa, showing both sundogs.  http://en.wikipedia.org/wiki/File:SunDog.jpg




8 comments:

angela said...

It never gets cold enough here for us to see them. Thank you for the photos and the information. Now I can act like Im really smart and tell people about sundogs.

TexWisGirl said...

I remember seeing them in Wisconsin. BRRRR!

Alison said...

Guess what? We've been seeing TONS of them in NC this winter! I didn't realize they were related to cold temps...heck, I never remember seeing them up north. But maybe that's because we never saw the sun between October and April...

Brenda said...

That's pretty cool. I've seen one that was a ring before, but didn't realize exactly what it was.

Nancy K. said...

I don't think I've ever seen them. VERY cool!

Louise said...

I have never seen one. I think that there are too many woods around here and by the time the sun is low enough to create them, it's sunk below the tree line. Thanks for the fun pictures.

Mom L said...

These shots are really cool, Claire - pun intended!

Nancy, your Iowa neighbor

My Life Under the Bus said...

I had never even heard of these before! Very cool.