Which factor influences the bending of waves as they approach the shore?

The bending of waves as they approach the shore, a process known as wave refraction, is primarily influenced by variation in water depth. As waves travel from deeper water into shallower water, they encounter resistance from the seabed. This change in water depth affects the speed of the waves; the part of the wave that is closest to the shore slows down first, while the part that is still in deeper water continues to move faster. This differential speed causes the wave to bend or refract towards the shore.

Understanding this concept is crucial, as it explains many coastal processes, such as how waves break at an angle, leading to longshore drift and the unique shaping of coastal landforms. Other factors mentioned, like wave height, salinity of water, and wind speed, do not directly cause the bending of waves in the same way that variations in water depth do.