You may be familiar with pyrocumulus (pyroCb) clouds that form over intensely burning vegetation fires. They can be a combination of smoke and condensation. Some firefighters call this “ice capping”.
Chuck Bushey, a Fire Behavior Analyst and former President of the International Association of Wildland Fire, is a member of a small group studying pyroCb led by Mike Fromm of the US Naval Observatory.
Chuck sent me a link to an animation of pyroCb forming over the Silver Fire recently in southern New Mexico, and explained:
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“…this is one recent example of the sort of products our small global pryoCb group watch. The group also examines lots of particulate and atmospheric information (some from ground based instrumentation such as Lidar, as well as from other satellite channels) to make sure it’s a real fire event or something else. There are other events that may look similar from orbit and some of the more remote incidents that this group sees we may be the first observers.
We can sometimes track these major upper atmospheric (stratospheric) events multiple times around the globe mixing with other weather systems. The most global round-trips I have observed has been four in the northern hemisphere.
We can only speculate on what the input of the volatile elemental and organic chemicals and other pyrolyized materials (such as soil and ash) are having on the cold, upper atmosphere and our climate. We also guess that these events may be more frequent now and maybe more intense than in the recent past but we really don’t know because no one was watching and our capabilities were limited.”
As soon as I saw the title of your article I thought of two things: 1. Watching the pyroCb form every day on the Silver Fire (my thanks go to the firefighters battling this blaze in such rugged country) and 2. When we were in West the guys called pyroCb “cumulus overtimes”.
that’s “cumulus overtimus”!