What causes most surface waves in the ocean?

The primary cause of most surface waves in the ocean is wind. When wind blows across the surface of the water, it imparts energy to the water, creating waves as the water molecules move in circular orbits. The strength and duration of the wind, along with the distance it travels over the water (called fetch), significantly influence the size and energy of the waves generated.

Other factors, such as seismic activity or underwater volcanic eruptions, can create waves, but these events are far less frequent and typically produce only particular kinds of waves, such as tsunamis, rather than the typical surface waves seen in everyday ocean conditions. Additionally, while boat traffic can create surface disturbances and localized waves, it does not account for the large-scale, consistent surf found across open waters like the wind does. Thus, wind is the uncontested primary factor in generating the most common types of ocean surface waves.