Density Currents

currents in the seas and oceans caused by the horizontal pressure gradients resulting from the nonuniform distribution of density in seawater. Permanent density currents, along with wind currents, play an important part in the overall circulation system of the surface waters of the world ocean. In the deep layers, where wind-driven currents are attenuated, density currents predominate. They are characteristic in straits between bodies of water with different densities. Owing to the Coriolis force, density currents move perpendicular to the horizontal density gradients.

The theory of density currents is based on the circulation theory of the Norwegian geophysicist V. F. K. Bjerknes. The theory was elaborated by the Norwegian B. Helland-Hansen, the Swede J. W. Sandström, and the Soviet scientist N. N. Zubov, who propounded the dynamic method of calculating sea currents from the distribution of water density.