Watch the video below, find some place freezing cold, then get ready to do some science:
The thermodynamics going on here is pretty straight forward. To make ice fog you need to fulfill three basic conditions: scalding hot water, frigid outdoor temperatures, and a decent throwing arm.
First, the water. The amount of steam that will be made boiling water is proportional to the temperature of the water — the hotter the water, the larger fraction of it becomes steam.
Next, the cold. When it’s absolutely freezing outside (the video above claims the air temperature is -30 degrees Fahrenheit or -34 degrees Celsius) the air can’t hold as much water vapor inside it. So when a bunch of steam is chucked into this cold air, millions of tiny water droplets rapidly condense out of it.
Finally, a decent throw. The more steam and water that is exposed to the air — the more surface area that the freezing temperatures have to work with — the more that can freeze before it hits the ground. Surface area is the same reason why granulated sugar, rather than a sugar cube, mixes faster into your morning coffee.
To recap: Get some water as hot as possible, take it into the arctic outdoors, and give it a strong, wide toss into the air. You’ve just made ice fog!
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This article is adapted from an earlier post at Scientific American.
IMAGE: -17 degrees by Jody
Ten below 0F is the magic number in Minnesota.
On the way out to work, I put my coffee in the microwave, called the kids to the window, stepped out onto the deck and flung the coffee in the air with a flourish, then got in the car and drove to work.
When I got home, the backyard snow was streaked with brown, the kids had gauze on their hands, my wife was glaring and the dogs were twitching and pacing until 4am.
So many people did this last winter here in Chicago.