Perhaps I’m old fashion, stubborn or stupid but there’s one subject I’ve never understood. When it’s mentioned I roll my eyes and mutter under my breath. My friends scorn me when I bring it up but I don’t mind. Anyway, dad always said never be a team player.
OK, here it goes. I don’t believe in wind chill.
No, sorry. None of this -20 degrees, “but with wind chill it feels like -35 degrees”.
And by “don’t believe”, I don’t mean “I don’t like being cold”, which-I-do-but-that’s-beside-the-point, what I mean is I don’t like the concept of wind chill.
The wind chill index was first developed in 1945 by Antarctic explorers Siple and Passel. It’s a measurement of the rate of heat loss from your body when you’re exposed to low temperatures combined with wind. It became popular in weather reports since the 1960s.
According to the National Weather Service, it can be calculated by “multiplying the temperature by 0.6215 and then adding 35.74. Subtract 35.75 multiplied by the wind speed calculated to the 0.16 power. Finally, add 0.4275 multiplied by temperature, multiplied by wind speed calculated to the 0.16 power. The result is defined as T(wc), which equals the current local wind chill factor.”
No problem, right?
The thing is, wind chill is a mathematically derived number that approximates how cold your skin feels and not how cold your skin actually is. It’s a perception and not an actuality. It just doesn’t make sense, temperature is supposed to be a precise measurement.
It’s measured by using a thermometer, which in many cases is a glass tube sealed at both ends and partly filled with a liquid like mercury or alcohol. As the temperature around the thermometer’s bulb heats up, the liquid rises in the glass tube. When it’s hot, the liquid inside the thermometer expands and rises in the tube. The opposite happens when it is cold.
Temperature isn’t a “feeling”.
According to Merriam-Webster dictionary, it’s “a degree of hotness or coldness measured on a definite scale”. The term definite does not mean an approximation or a “well it feels like”. It either is or isn’t.
Part of the reason, I think we use wind chill is because it makes temperatures sound more dramatic and tough. Minus 15 degrees doesn’t sound bad, but if with the wind chill it feels like -37 degrees, that’s far more impressive on Facebook. Selfie to grandma!
Of course, wind does accelerate heat loss from the body. And the faster the wind, the faster the heat loss. However, wind chill is all about perception and the wind chill index is an attempt to gauge that perception.
Some meteorologists say it would be far more useful instead of reporting wind chill to say how many minutes until frostbite.
If you’re still not convinced that wind chill isn’t real, try this. Get two thermometers and place them outside. One in the wind and the other shielded. Go inside, have hot cocoa and when you return they will read the same. The same is if you’re driving. If you’re going 80 km/h and it’s -20 degrees and you decide to drive 100 km/h, does the thermometer drop? Of course not. There’s no wind chill for vehicles.
Perhaps wind chill is part of our desire to describe everything to a pinpoint. Flowers can’t just be flowers, they have to be something like Pinguicula vulgaris or Chamaenerion angustifolium. Only amateurs don’t describe plants to species level in Latin. There must be a name for everything.
So, when people turn to me in shock and say it’s -40 degrees outside, I can’t help but politely ask, “is that with wind chill?”
Liam Harrap is a reporter with the Revelstoke Review