Whether you’re an experienced camper or you’re looking to go on a trip this summer, campfires can keep you warm, cook your food, be something to bond over with friends, and, of course, smores. But even though campfires are a beloved tradition, there are some slight nuisances — one of which is dealing with excess smoke. Hank Green, a producer of SciShow on Youtube, explains the physics of why it can be so hard to escape being surrounded by campfire smoke.
Photo: Juliya ShangareyShutterstock
Watch: Here's Why Campfire Smoke Always Blows in Your Face
It turns out the smoky problem is airflow. As the campfire releases its energy as heat, that heat is absorbed by some air molecules, making them move faster. The slower air molecules collide with the speedy ones causing them to move in the opposite direction, and the air near the fire becomes less dense than the air around it, causing it to rise. The denser air pushes that air until it runs into an object. That object is you.
This explains why smoke ends up in your eyes. But why can’t you escape it? The wall your body creates starts a vacuum. So the air behind you can’t get toward the fire, and the air coming from the fire can’t escape you. This will continue to happen regardless of where you move to, and the more friends you have with you, the bigger the wall is.
There are a few options to avoid this smoky nonsense. The first is to create a smokeless fire pit with additional paths for incoming air. The other is to equidistantly separate you and your friends around the fire, giving the smoke enough of a pathway to travel through. It turns out the answer all along was a little social distancing.
Remember with great fire comes great responsibility. Be sure you know how to start a campfire properly in difficult weather conditions, and how to put out a campfire safely. And if you’re traveling somewhere where wildfires are a huge problem, there are definitely tricks for camping without fire. 