Wind Chill Factor: Definition, Measurement & Impact

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The wind chill factor is a measure of how cold it feels to humans due to the combined effects of temperature and wind speed, and it is not directly measurable by conventional mercury thermometers. Wind chill only applies to living beings, as humans experience evaporative cooling and heat loss, making them feel colder than the actual air temperature. Different wind chill scales exist, such as those used by the Navy, US, and Canada, leading to some confusion in temperature perception over time. Humans differ from thermometers in that they generate heat and can be insulated by a layer of air, which wind can disrupt. Understanding these differences is crucial for accurately assessing cold weather conditions.
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What exactly is the wind chill factor? Do conventional mercury thermometers measure the wind chill factor?
 
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Thanks for that link, Mgb. I've had a bit of trouble adjusting to the new standard. It sounds so much warmer these days, while I remember it hitting 75° below F. when I was a kid. Now it's like -50 C. and feels the same. Even accounting for the conversion between F & C, the numbers are considerably different.
 
Hello
Thank you for your replies. In what ways is a human different to a thermometer, that would mean the former are subseptible to the wind chill factor while the latter are not?
Thanks
 
The human differs from a thermometer because (1) the human skin is moist, and in the presence of wind, this leads to evaporative cooling, and (2) the human body generates heat, so there is a heat flux from the body surface to the ambient environment. You can "feel" the effect of wind, the idea is that when the wind blows, it "feels" to you like the air is colder. The various wind chill scales (in my opinion) all have their own problems.
 
p.tryon said:
In what ways is a human different to a thermometer, that would mean the former are subseptible to the wind chill factor while the latter are not?

Hello p.tryon! :smile:

A thermometer is the same temperature as what it is measuring, but a human is usually warmer. :wink:

(So a human can be insulated by a surrounding layer of air, which the wind can make thinner.)
 
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