Thursday, January 5, 2012

A Question About Wind Chill

I received the following e-mail from a CBS 6 viewer a couple of days ago addressing wind chill, and who or what is affected by it. Read the message first, and then continue reading for my explanation below.


Zach,

While over at a friends farm Monday it was cold and windy. We got in his golf cart to go look at something and the gas engine stumbled and stammered at first and my friend blamed it on the wind and cold. I tried to explain the wind didn’t make the engine any colder but he wouldn’t hear of such a foolish thing. It might be worthwhile if you or Carrie try to explain the difference between wind chill and ambient temp while this dip has everyone's attention!

Thanks,

Mike
A lot of people will tell you that wind chill does not affect inanimate objects, while others will tell you wind chill affects everything, both living and otherwise. The answer is actually not that cut and dry. The simplest way to put it, is to say that wind chill affects all objects that are emitting heat, causing them to cool to the ambient air temperature faster. So in the example above, the cold could be a reason for the engine to struggle, but not the wind. In the same way, if a lake is 33 degrees and the wind is calm, the lake will not freeze if the wind increases to 20 mph and the wind chill drops into the teens. The wind chill will be sensed by humans and other objects warmer than the surrounding air temperature, but the temperature of the water will not cool lower than the air temp and freeze. Wind chill accelerates the cooling process of objects, and if those objects are already at the ambient air temperature, they won't get any colder regardless of how low the wind chill drops. -Zach