Which natural factor affects a diver's buoyancy?

A diver's buoyancy is primarily affected by the amount of air in their lungs. When a diver inhales, the air in their lungs makes them more buoyant because the air is less dense than water. Conversely, when a diver exhales, they decrease their buoyancy since the volume of air in their lungs is reduced. This principle is crucial for divers, as managing buoyancy is essential for maintaining control underwater and ensuring safety during dives.

Water temperature plays a role in overall buoyancy but does not directly influence the diver's specific buoyancy in the same manner as air in the lungs. The color of the wetsuit does not impact buoyancy at all; it is more related to thermal protection and visibility. Time spent underwater influences the diver's physiological state and the effects of nitrogen absorption but does not directly alter buoyancy in the way that lung volume does. Thus, the presence and manipulation of air in a diver's lungs is the key factor that determines their buoyancy while diving.