Gravity wave

Atmospheric gravity waves as seen from space.

Do not confuse with gravitational wave.

In fluid dynamics, gravity waves are waves generated in a fluid medium or at the interface between two mediums (e.g. the atmosphere or ocean) which has the restoring force of gravity or buoyancy.

Gravity Wave Media

Surface gravity wave, breaking on an ocean beach in Tučepi, Croatia
Wave clouds over Theresa, Wisconsin, United States
Wind-driven gravity waves in the Timor Sea, Western Australia, as seen from space

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