Mixed Layer

A MIXED LAYER is a quasi-homogeneous turbu-lized layer in the worlds ocean. Its upper boundary directly contacts with the atmosphere boundary layer, while the mixed layer bottom contacts with underlying thermocline. That is why mixed layer is also called the upper mixed layer. Vertical gradients of temperature and salinity within the mixed layer usually do not exceed 0.01 Kelvin degrees and 0.01 promille per meter. Mixed layer is formed as a result of turbulent mixing by thermohaline convection, vertical shear of oceanic currents, and surface waves (periodically breaking when their slope reaches some critical level).

The process of mixed layer deepening is accompanied by entrainment of more cold water of thermocline into the upper turbulized layer. This leads to negative mixed layer heat fluxes at its ...