2006 LAYERED OCEAN MODEL WORKSHOP

A refined bulk mixed-layer is compared and tuned to the solution of a k-profile mixed layer model. Single column physics (SCP) mixed-layer models are adapted from the Hallberg Isopycnal Model (HIM) and the Modular Ocean Model (MOM4).  The former being the refined bulk mixed-layer and the latter KPP. The models are initialized and forced using data from coupled general circulation models (CM2) experiments. Single column water profiles span the globe in an attempt to capture as many scenarios as possible. The SCP bulk mixed layer model, using default parameter settings, produces solutions closer to those of the SCP KPP model than anticipated.  Exploration of parameter space shows that most parameter adjustments move the solutions apart. The exceptions are those parameters involved in relating turbulent kinetic energy input from the surface to the surface friction velocity and parameters used to determine the Richardson dependent mixing within the bulk mixed layer. "Optimal" parameter settings are applied to the refined bulk mixed layer in a HIM CM2 expirement run. The solution shows little sensitivity to the parameter adjustment. Non-local processes and atmospheric feedback appear to dominate the details of the refined bulk-mixed layer parameterizations.