How many feet in seawater is equivalent to one atmosphere in the ocean?

One atmosphere of pressure is equivalent to the weight of the air above us at sea level, which is approximately 14.7 pounds per square inch. In underwater environments, the pressure increases with depth due to the weight of the water above the diver. Specifically, for every 33 feet of seawater, the pressure increases by about one atmosphere. This relationship is based on the density of seawater and the gravitational pull of the Earth.

Thus, when you dive to a depth of 33 feet, you experience an additional atmosphere of pressure on top of the one atmosphere already present at the surface. This principle is fundamental in understanding how pressure affects diving, as well as concepts like buoyancy and decompression. Knowing this allows divers to make safe ascent and descent plans and assists in understanding the physiological effects of pressure on the body during a dive.