Why aren't we crushed by the weight of Earth's atmosphere?
Miles of air cover Earth. The boundary between Earth's atmosphere and outer space, the Kármán line, is about 62 miles (100 kilometers) above the planet's surface. However, about 99.9% of the mass of Earth's atmosphere lies below a height of 30 miles (48 km), according to Anthony Broccoli, a professor of atmospheric science at Rutgers University.
Air is lighter than our bodies, but all those miles of air in the atmosphere amount to a lot of weight. "The total mass of Earth's atmosphere is 5.1 billion billion kilograms, or 11.24 billion billion pounds," Broccoli told Live Science. When it comes to a cylindrical column of air that is 1 foot (0.3 meters) in diameter, "its mass is 1,663 pounds [754 kilograms]," he said.
In part, it comes down to the distribution of the pressure. Air flows around your body. Ultimately, the pressure from air "is exerted uniformly on all parts of a person's body — it is not just a downward force," Broccoli said.
Still, the pressure the atmosphere exerts uniformly on our bodies is not trivial. It amounts to approximately 14.7 pounds — about the weight of a large bowling ball — per square inch (1 kilogram per square centimeter), Broccoli noted.
