Version 5 (modified by mlelod, 9 years ago) (diff)

Last edited Timestamp?

Author : Matthieu Leclair

ticket : #863

Branch : z_tilde coordinate

The z_tilde vertical coordinate

Implementation of the z_tilde Arbitrary Lagrangian Eulerian vertical coordinate discribed in Leclair & Madec, Ocean Modelling, 2011

Baroclinic high frequency vertical motions are followed by the coordinate (Lagrangian part) while barotropic and baroclinic low frequency ones are discribed through cross-level velocities (Eulerian part).

Structure description

z_star and z_tilde vertical coordinates are now two possible "sub-options" of the vvl key. A third one, the full layer coordinate has been introduced for academic and debuging purposes.

Next sea surface height is first computed. The latter is necessary before computing next vertical scale factors. And now vertical velocity (eulerian cross-level velocity) can then be calculated.
After this sequence, tracers and dynamics terms can be computed. Next tracers and dynamics fields are updated.
Finally, after the swap of those fields, sea surface height and vertical scale factors can be swaped.

Calling sequence in step.F90 before tracers and dynamics:

               CALL ssh_nxt       ( kstp )
IF( lk_vvl )   CALL dom_vvl_sf_nxt( kstp )
               CALL wzv           ( kstp )

Calling sequence in step.F90 after tracers and dynamics:

               CALL ssh_swp       ( kstp )
IF( lk_vvl )   CALL dom_vvl_sf_swp( kstp )


Testing could consider (where appropriate) other configurations in addition to NVTK].

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