The Model (11)
Two hybrid-coordinate K-T mixed layer models have been developed.
K-T 1: Full model
This version has a prognostic mixed layer base. At a given grid point,
the base is contained within layer k and divides this layer into two
sublayers (see diagram on previous slide). T and S are estimated
within these sublayers by “unmixing” each variable, then the TKE
balance is calculated as in the MICOM K-T mixed layer.
K-T 2: Simplified model
This version was developed by Rainer Bleck to avoid unmixing and
the associated computational overhead. At each grid point, the mixed
layer base always resides on a vertical coordinate interface.
When HYCOM is run in MICOM mode, the MICOM 2.8 Kraus-Turner mixed
layer model is used. The mixed layer base coincides with vertical coordinate
interface 2 (layer 1 is the slab mixed layer). Another major difference from the
hybrid-coordinate K-T models is the detrainment algorithm, since the density
of detrained water must match the isopycnic reference density of the layer
accepting the water.