Course Outline

Wind causes waves on the ocean or freshwater lakes. The wind transfers its energy to the water through friction between the air molecules and the water molecules.

A strong wind for several hours can make large waves, which are hazardous to diving. A wind that turns and then comes in from another direction usually flattens waves, reducing their energy. When waves arrive in shallow water, they break as surf. Surf is created when the speed of water in contact with the seabed slows down (due to friction), and this causes the top of the wave to become unstable and break.

You will need to learn special techniques for surf entries and for timing your entries and exits through the surf zone while watching the wave pattern. Timing your entry and exit to avoid the full force of the waves makes sense because waves can approach from different directions, which can build very large and powerful waves. Sometimes, too, these collisions can cancel the wave’s energies out and make a series of smaller and less challenging waves. Diving in large surf makes for low visibility and hazardous conditions.

Tidal waves or tsunamis are typically caused by underwater volcanic eruptions, earthquakes, or landslides. And they are rare occurrences.

Wind creates friction between air and water molecules.
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