Why do waves break on the shore?

Hello, I'm an expert in fluid dynamics and coastal processes. Let's dive into the fascinating phenomenon of why waves break on the shore. Waves are formed by the wind blowing across the surface of the water. As they approach the shore, several factors come into play that cause them to break: 1. Shallow Water: As the wave moves into shallow water, the bottom of the wave slows down while the top continues at the same speed. This causes the wave to bend and steepen. 2. Wave Refraction: When waves encounter a shoreline with varying depths, they refract, or bend, towards the shallower water. This can cause the wave to increase in height as it approaches the shore. 3. Wave Interference: Waves coming from different directions can interact with each other, causing them to steepen and break. 4. Wave Energy: The energy within the wave increases as it approaches the shore, and when the wave's height becomes too great for its own length, it collapses under its own weight. 5. Orbital Motion: The circular motion of water particles within the wave causes the water at the bottom of the wave to move forward faster than the water at the surface, leading to the wave breaking. 6. Tides and Currents: The presence of tides and currents can also influence how and where waves break. 7. Bathymetry: The shape and contour of the seafloor can cause waves to break in specific areas. When all these factors combine, the wave's crest collapses, and we observe the wave breaking on the shore. This is a critical process in the transfer of energy from the ocean to the shore, which can lead to erosion and the shaping of coastal landscapes.

Observe waves as they break on the shore. When wave energy passes through water into a shallow area, the waves break. The lower part of the circular motion slows down as it scrapes the shallow bottom, and the upper part of the wave continues moving forward until it falls into air, or breaks.