Final answer:
The depth at which a scuba diver would no longer encounter wave motion is the oceanic zone, starting at 200 m deep. Managing pressure differences through proper ascent techniques and controlled buoyancy is crucial to prevent DCS.
Step-by-step explanation:
The depth at which a scuba diver descending from the surface would no longer encounter any wave motion is known as the oceanic zone. The oceanic zone begins where the water measures 200 m deep or deeper. Below this depth, the weight of the water column is significant enough to suppress the energy associated with surface waves, making it a calm environment for divers.
When diving, it is important to manage the pressure changes experienced with depth to avoid decompression sickness (DCS). As divers ascend, the ambient pressure decreases and can lead to the formation of gas bubbles in the body if the ascent is too rapid. Proper ascent techniques, including decompression stops and controlled buoyancy, help prevent DCS and manage the risk associated with rapid pressure changes.