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How can strong winds change water levels and currents in a lagoon?

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lagoons — lagoon Lagoons lie behind the coral reef and barrier islands surrounding Raiatea and Tahaa in the Society Islands, Pacific Ocean.

Strong winds significantly influence the dynamics of a lagoon by altering both water levels and flow patterns. When strong winds blow toward a lagoon, they can force water into the basin, causing the water level to rise. Once these winds subside, the elevated water often creates an outflowing current as it returns to equilibrium.1

Additionally, these wind-driven forces can generate seiches, which are rhythmic oscillations of water within the partially enclosed basin. Winds blowing along the maximum dimension of a lagoon can also generate small waves, which may reach heights of up to 1.25 metres (about 4 feet) depending on the specific environment. While these processes primarily affect water circulation, severe storm winds can also cause more dramatic changes, such as breaching or overtopping barrier islands, which temporarily raises water levels and can lead to the formation of new washover channels.12