Ice Crystals at Work in the Upper Atmosphere

There were some ice crystals in the upper atmosphere around here over the last two days, so several sky phenomena caught my attention while I was out and about. This morning, light rays from the sun reflecting off of the platy crystals produced a 22° ice halo (above), and a sun dog (below).

Last night I noticed an odd glow in the sky as the sun was nearly setting. It was a sun pillar, which is also a consequence of sunlight reflecting off of horizontal ice crystals.

Picture of My Hand. Oh, and Some Sun Dogs with an Ice Halo

I was out at the San Joaquin National Wildlife Refuge this afternoon, checking on what migrant birds are still hanging around as we approach spring. I noticed some sun dogs in the western sky, and snapped a shot or two, but the bright sun was causing lens flares that were messing up the shots. It finally occurred to me to put my hand in front of the sun and suddenly I saw something I've never seen or noticed before: a 22° ice halo around the sun.

The sun dogs (also called mock suns or phantom suns; scientists call them parahelia) are caused by the refraction of sunlight through hexagonal ice crystals in the upper atmosphere. The rainbow colors in the sun dogs themselves happen because of the prisming effect of the crystals.

Either that, or I have summoned forth the twin solhundes (sun wolves) of Norse mythology...