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On the Costa Brava, as in Tossa de Mar, it is known as the "barrumera", the foam that we see in the sea and that, in this photograph in Las Fotos de los Lectores de La Vanguardia, has leaked between the boats.
Sea foam is created by the agitation of seawater and the Costa Brava is a specialist in this, as its name suggests. It is produced particularly when it contains high concentrations of dissolved organic matter (including proteins, lignins and lipids).
This is obtained from sources such as the offshore distribution of algal blooms and iodine. These compounds can act as surfactants or foaming agents.
As seawater is churned up by breaking waves in the offshore wave zone, the presence of these surfactants in these turbulent conditions traps air, forming persistent bubbles that stick to each other through of surface tension.
Due to its low density and persistence, the foam can be blown by strong onshore winds from inland on the beach.
