Mixed‐layer dynamics and buoyancy transports

Ocean mixed layer (ML) dynamics are considered in the framework of a self‐similar buoyancy profile governed by the Kraus‐Turner budgets. The global validity of the profile is suggested by an inspection of Levitus‐data. A parameterization of the mechanical energy forcing in terms of surface winds and heat fluxes is tested against weathership data in 1‐dimensional (1D) model experiments. The ML‐model is furthermore incorporated into a 3D transport‐theory, where the consideration of 2 transport equations accounts for the Kraus‐Turner concept. To test the transport theory, relative geostrophic velocities are derived from buoyancy‐data. In addition to ML‐dynamics, the empirical buoyancy‐profile provides a convenient representation of this velocity field. For the mid‐latitude Pacific, it is shown that these velocities, in conjunction with observed surface velocities, yield a realistic estimate of advective buoyancy‐fluxes.