barnson.org Half-baked opinions, served lukewarm.

This was sent to me by "Peggy" on one of my mailing lists. Hope you enjoy the picture. It's one of many things convincing me that St. Helens still has a lot of life left in her.

"MT. St. Helens, which sits about 30 miles from our house as
the crow flies, continues to spew ash, while it is forming a lava
dome in the crater and still having minor tremors. Here, in this
sunrise shot, she appears to be blowing smoke rings (and
anything so benign is welcomed, given recent history.)

Picture by Brent and Jan LeBaron

What forms the "smoke rings" is the air flowing over the
mountain getting pushed up higher as it goes up and over the
top. The moisture content and initial temperature are just right
so that the moisture condenses from a vapor to small particles
at the higher altitude. When the moving air moves past the peak
and comes down again, the particles evaporate back to an
invisible vapor. The two "pancakes" describe that there are two
layers of air for which this is happening, thus making this
awesome picture possible."