eddy visosity eddy diffusivity vertical mixing

[onken]

(1) What is the default scheme for horizontal eddy viscosity and diffusivity? In the options.h file, I did neither define UV_VIS2 nor UV_VIS4, TS_DIF2, or TS_DIF4. The CPU time of that ROMS run was much less compared to a run with UV_VIS4 and TS_DIF4 but the results were approximately the same.
(2) Same for the vertical mixing scheme: what is the default scheme if no options for vertical mixing are specified?

Reiner

[kate]

For the horizontal smoothing, the only way you can get away with no explicit values is if you use the third-order upwind advection scheme with its implicit smoothing.

If you do nothing at all for vertical mixing, Akv and Akt are set to Akv_bak and Akt_bak, respectively. These values come from the ocean.in file.