Wed Dec 31, 2003
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Making snow can make the difference between huge profits and losses in the ski industry. Hi,
I'm Bryan Yeaton and this is The Weather Notebook. Resorts worldwide invest millions of
dollars in snowmaking equipment to ensure more ski-able days on the slopes. Jeff Rice tells us
how the fluffy stuff is made.
JR: When it snows, nature begins the process tens of thousands of feet up above the earth, and
the intricacies of humidity and physics are able to create beautiful lattice-works of light
and fluffy snowflakes: no two alike and a skier's dream. Manmade snowmaking systems, on the
other hand, blow tiny droplets of water into the freezing air from compressed air guns,
creating what are known as "graupels."
PS: Like a hail when you hold it in your hand, a graupel is just a round snow particle. It
doesn't have any arms or legs.
JR: Peter Stearns is the director of snowmaking at Sun Valley resort in Idaho. Sun Valley has
one of the largest snowmaking systems in the world. And while Stearns acknowledges it's
impossible to truly recreate the real stuff... modern machines are a big advance over the
early techniques in the 1950s.
JR: This is a hydrant, and there's a little microprocessor inside there that the computer
talks to via all these little wires that run everywhere. We decide what kind of snow we want
here if we're going to put snow out on the ski slope we would decide to make a real nice dry,
ski-able snow. You do that right at a computer terminal with the click of a mouse.
JR: Computers regulate air to water ratios to create drier mixes, for lighter, less icy
snow... All you need are freezing temperatures and a whole lot of water -- It takes about
150,000 gallons of water to cover a single acre with one foot of man-made snow.
Correspondent Jeff Rice reports to us from Boise, Idaho. The Weather Notebook is supported by
grants from the National Science Foundation and Subaru, Driven By What's Inside.