Nugget of Knowledge: Wind chill history

The wind-chill factor accounts for heat blown from your body

YOUNGSTOWN, Ohio (WYTV) – Two researchers with the U.S. Antarctic Expedition, Paul Siple and Charles Passel, first tested wind chill in the 1940s.

They filled a plastic container with water, hung it outside and measured how quickly the water lost heat, and how long it took to freeze when the wind blew.

The faster the wind, the faster the water turned to ice.

A few Canadian forecasters used their measurements, but not many others.

The National Weather Service began using the wind chill factor in 1973 to describe our comfort level, but water and skin have different cooling rates.

The researchers revised the numbers in 2001.

They calculated wind speed at five feet above the ground, the average height of a human face. They measured heat flow with sensors on exposed cheeks, forehead, nose and chin: Volunteers walked on a treadmill at three miles an hour in a cold wind tunnel.

All of this assumes there is no sunshine.

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