In fluid dynamics, gravity waves are waves generated in a fluid medium or at the interface between two media when the force of gravity or buoyancy tries to restore equilibrium. An example of such an interface is that between the atmosphere and the ocean, which gives rise to wind waves.
Surface gravity wave, breaking on an ocean beach in Tučepi, Croatia
Wave clouds over Theresa, Wisconsin, United States
Wind-driven gravity waves in the ocean at Shark Bay, Western Australia, as seen from space
In fluid dynamics, a wind wave, or wind-generated water wave, is a surface wave that occurs on the free surface of bodies of water as a result of the wind blowing over the water's surface. The contact distance in the direction of the wind is known as the fetch. Waves in the oceans can travel thousands of kilometers before reaching land. Wind waves on Earth range in size from small ripples to waves over 30 m (100 ft) high, being limited by wind speed, duration, fetch, and water depth.
A man standing next to large ocean waves at Porto Covo, Portugal
Aspects of a water wave
NOAA ship Delaware II in bad weather on Georges Bank
Surf on a rocky irregular bottom. Porto Covo, west coast of Portugal
