Why seawater foams more readily than freshwater

Determine the physicochemical mechanisms that cause seawater to foam more readily than freshwater.

Background

Foaming is commonly observed in ocean waves, whereas pure liquids do not foam. Salts in seawater are known to influence foam stability, yet the exact mechanisms have historically been debated and difficult to pin down.

This paper uses interferometric single-bubble experiments and revisits Marrucci's 1969 theory to investigate salt-induced stabilization via surface tension gradients and Marangoni flows, aiming to clarify this long-standing question.