"That's Telling You There's a Lot of Ash"
The readings, the team now reports, reveal that volcanic lightning storms can be as powerful as giant Great Plains thunderstorms and that more lightning means a bigger plume.
"If you get lightning," said report coauthor Stephen McNutt, "that's telling you there's a lot of ash."
That ash can spell trouble for air travelers, who may welcome another of the project's findings: that radio sensors can detect the beginnings of big plumes before they're visible to other instruments.
—Richard A. Lovett