What causes waves to break on the shore?

Hello, I'm an expert in coastal and oceanographic studies. When it comes to understanding why waves break on the shore, there are several key factors at play. Waves are formed by the wind blowing across the surface of the water. As these waves travel towards the shore, they interact with the shoreline's topography and the depth of the water. Here's a step-by-step explanation: 1. Wave Generation: Waves are generated by the wind blowing over the surface of the ocean or sea. The size of the waves depends on the wind's speed, duration, and the distance over which it blows (fetch). 2. Wave Approach: As waves move towards the shore, they start to interact with the seafloor. The depth of the water becomes a critical factor. In deep water, waves pass freely without much change in their form. 3. Wave Refraction: When the wave approaches a shoreline with varying depth, it will bend or refract. This is because the part of the wave that is in shallower water slows down while the part that is in deeper water continues at a faster pace, causing the wave to bend towards the shore. 4. Wave Shoaling: As the wave continues to move into shallower water, it slows down and its height increases. This process is known as shoaling. The wave's energy becomes more concentrated, and the top of the wave begins to steepen. 5. Breaking Point: When the wave's steepness reaches a critical point, the top of the wave can no longer maintain its shape and it breaks. This is the point at which the wave's speed at the base is greater than the speed at the top, causing the top to collapse under its own weight. 6. Wave Dissipation: After breaking, the wave's energy is released and it dissipates as it crashes onto the shore, creating surf and swash. 7. Beach Slope and Composition: The slope of the beach and the type of material (sand, pebbles, etc.) also influence how and where waves break. 8. Tides and Currents: Tidal movement and currents can also affect the breaking of waves, as they can alter the depth and slope of the seafloor in the nearshore area.

Onshore winds do the opposite. They accelerate the breaking process. Nevertheless, ocean floor topography will critically decide how wave energy will transform into whitewater. As waves reach the shore, the energy in front of the wave slows down due to friction with the shallow bottom.