35.1.9.2 gkw_taper

If option gkw_taper is enabled, the algebraic tapering of Gerdes et al. (1991) is used

$$taper = \left( \frac{slmx}{\vert S\vert} \right)^2.$$ (35.77)

This is the MOM3 default tapering option. In this case, when the slope is larger in absolute value than slmx, then the effective diffusivities take the values

$$(A_{I}, \kappa, B)_{effective} = taper * (A_{I}, \kappa, B)_{un-scaled}.$$ (35.78)

To determine when to taper, an if-test is required. This taper is much weaker than that used with option dm_taper. However, preliminary tests indicate the absence of much difference in the large scale features in coarse models between the different tapers.

Note that neither gkw_taper nor dm_taper apply to option full_tensor, which is re-scaled as given in Section .