Semianalytical Simulation of the Meridional Cells in the Southern Ocean

Abstract

The dynamics of the meridional cells in the Southern Ocean simulated by a primitive equation model are investigated. Particular attention is drawn to the Deacon cell, which transports about 15 Sv (Sv≡106 M3 s−1) from the surface between 45°S and 35°S down to 2500 m without crossing any isopycnals. A theory of the Deacon cell is presented using a Sverdrup–Munk-based model with an Ekman layer at the surface. The simple model successfully simulates a Deacon cell when applied to the Southern Ocean. The explanation of the Deacon cell appears to be the depth differences of the western boundary current and the Sverdrupian interior flow. The theory is extended to the other cells in the Southern Ocean by replacing the Sverdrup solution with a Luyten, Pedlosky, and Stommel solution. These other cells are driven at the surface by the ventilation provided by the Ekman pumping.