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.