Sea state

In oceanography, sea state describes the general condition of the free surface of a large body of water with respect to wind waves and swell, at a given location and moment. It is characterized through statistical measures such as wave height, wave period and the wave spectrum, generally assuming that conditions remain relatively stable over a period of roughly fifteen to thirty minutes. Sea state can be assessed by trained mariners through direct observation or measured using instruments such as weather buoys, wave radar or Earth observation satellites.