November 20, 1998 transcript # 260-5
Subject(s): brainstorm
Title: Brainstorm Answer: Fire And Ice

How do you get fire from ice? That's the question in a recent Weather Notebook Brainstorm posed to you, the incredibly insightful listening audience. Hi, I'm Dave Thurlow. That Brainstorm question was, "What weather phenomenon requires ice in order to produce fire and how?" Well, a surprising number of people called in with this type of response, including Jack Henton, who listens to the fabulous WMRA in Harrisonburg, Virginia.

Jack: "You would shape a clear piece of ice into the shape of a magnifying glass, allow intense sunlight to shine through it to combustible materials."

Now, that's a pretty good idea, and it probably works, but don't try it at home. But, it's not really the answer we were looking for.

That answer comes courtesy of Bill Waste in Lyme, NH-- just down the road a piece-- who e-mailed in his answer. He wrote.

Bill: "I believe the answer to that question is found in the heart of a thunderstorm. The vertical circulation of air in a thunderstorm carries moisture along with it. It causes the clouds to rise to spectacular heights we can see when viewing a storm from a distance. When carried to heights where the air is below freezing, the moisture condenses into droplets and then turns into ice pellets. Often these are cycled up and down through the storm many times. As the ice moves through the storm, it helps to build up a static electric charge, much the same way socks do when tumbling in a dryer, they build up a static charge, and ultimately this pent-up energy releases itself from the cloud as lightning."

Well, that's it: fire from ice, in a thunderstorm. Remarkable.

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