A thin skim of ice formed on the Bras d’Or Lake this weekend, and the forecast week of bitter cold and light winds promises to deepen and strengthen its wintery cover. Forty years ago, this was an all-but-annual occurrence. In the middle decades of the 20th Century, Victoria County’s legendary physician C. Lamont MacMillan routinely crossed the lake in a homemade half-track to reach ill patients in the depths of winter. But as our climate has changed, the frozen lake has become a rarity.
Consider this a placeholder for a compilation, coming soon, of the outraged comments that flooded in from defenders of the “wind chill” notion, in response to Contrarian’s (and Scientific American’s) repudiation of the concept.
(I will just note in passing that it is an absence of significant wind, as much as extreme cold, that allows the Bras d’Or freeze over. Quelle ironie!)
Scientific American calls bullshit on wind chill:
[I]f the air temperature is, say, 15 degrees F, and a 20–mile per hour wind makes the wind chill –2 degrees F, would the temperature of your exposed skin drop to that temperature?
No. Your skin temperature cannot drop below the actual air temperature. The coldest your uncovered face could get would be 15 degrees F whether the wind is calm or howling at 40 mph….
Try an experiment: Put two thermometers outside, one in the wind and one shielded from it. When you return they will read the same. Or just ask yourself a simple question: If you are driving your car at 20 mph and you read the dashboard thermometer, then speed up to 60 mph, does the temperature drop? No. Because the air temperature has not changed. There is no wind chill for your car—even if you have given your vehicle a human name.
Wind chill is an artificial construct that makes temperatures sound worse than they are. A parallel set of fake numbers makes summer temperatures sound worse than they are. Both serve the interests of broadcasters who seek to exploit public fears about their personal safety by fanning them with constant hype and faked data like “wind chill.”