In 1946 Vincent J. Schaefer discovered how to turn a "supercooled" cloud into
a miniature snowstorm in the laboratory. In 1961 Ed Holroyd, still in high
school, learned from Dr. Schaefer how to make such snow. For many decades
since then Dr. Edmond W. Holroyd, III, has been repeating the demonstration,
making it snow in classrooms and other locations.
The usual demonstration is designed for classroom use, particularly during
25-minute periods (with 5-minute class change breaks) at Water Festivals
(such as the
Aurora Youth Water Festival).
Class sizes of about 25 upper elementary students are typical.
Older students and adults also appreciate this presentation that makes it snow in a classroom at any time of the year. One of my most unusual presentations was to make it snow in a kitchen freezer in Phayao (northern) Thailand for students who had never seen snow in their lives. It was then floating in front of them.
Similarly, on 9 July 2024 I repeatedly made it snow in a classroom at the University of Monsatir, Tunisia (North Africa or southern Mediterranean), somewhat north of the Sahara Desert. The audience was of graduate students in the sciences, working on their Ph.D. degrees. I have two video clips. (Use your Back Arrow to return to this page after each video clip.)
This closeup is from a video camera aimed at a small volume of air within the freezer. A string and twig serve as targets for camera focus.
One of our teachers made this video during a demonstration before some students.
The instant snowstorms can easily be created by others, including at home, if the right equipment is available. In addition to teaching some basic cloud physics concepts, the demonstration lets the viewers actually see some of them work right in front of their eyes (and hands).
Many of the illustrations on this web site are from photographs taken by Jack
Pelon, the radio station manager of Denver's KPOF
(AM91) during an open house
of their facilities in the "big red castle". The "instant snowstorms" were
made in the basement on October 11, 2008.
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sequence,
equipment,
clouds,
vapor growth,
snowstorm,
crystal growth,
cloud seeding history,
related topics,
water optics,
ice optics,
trouble shooting