With the long weekend upon us, Canadians will likely be spending the next few days by the lake or in their backyards, gathered around a campfire.
With that familiar sight also comes a familiar question: why does campfire smoke seem to follow you everywhere you go?
It turns out the answer comes down to physics.
“What ends up happening is that the fire heats the air and that creates buoyancy, which is the scientific term for rising hot air,” research scientist Kerry Anderson told CTVNews. ca during a telephone interview on Saturday.
Based in British Columbia, Anderson spent more than 30 years with the Canadian Forest Service and currently works for Environment Canada modeling wildfire smoke for the FireWork prediction system.
He said that because hot air is less dense, it lifts up and creates an area of low pressure which draws surrounding air into the fire in order to fill that area.
When someone stands next to a fire, they essentially create a barrier, or shadow, that prevents surrounding air from being drawn in, creating another area of low pressure, Anderson explained.
“And what ends up happening is that the warm air that rises ends up being brought into that vacuum, so it’s pulled towards you,” he said. “And with your head atop your body, the smoke is sucked into your eyes.”
A person’s height, distance from the fire, whether they are standing or crouching, wearing a large jacket or blanket, or sitting in a chair will affect the size of this barrier and the force with which the smoke will be drawn into its focus. Face.
For those looking to enjoy a campfire this weekend, Anderson said one way to minimize this phenomenon is to have people position themselves evenly around a fire so the smoke isn’t not attracted to one person.
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