Why does water pressure increase with depth?
At sea level, Earth’s atmosphere pushes down with about 14 pounds of pressure per every square inch. This is because the gasses in the atmosphere have weight. Above sea level, however, the atmosphere thins. Water is much denser than the atmosphere, and thus weighs more and will exert more pressure on anything submerged in it. As depth increases, the amount of water pushing on water increases, so at lower depths the water is actually denser and weighs more. This means that pressure increases with depth.
