Mesoscale momentum parameterization with ANN

[Pperezhogin]

This PR implements ANN parameterization of mesoscale eddies. Changes to the main branch include:

• Module for ANN inference MOM_ANN.F90
• Computing subgrid stress using ANN in MOM_Zanna_Bolton.F90

Default MOM_override for ANN usage:

#override USE_ZB2020 = True
#override USE_ANN = 3
#override ANN_STENCIL_SIZE = 3
#override ANN_TRUE_VORTICITY = True
#override ANN_FILE_TALL = /path/to/ocean3d/subfilter/FGR3/EXP1/model/Tall.nc

The netcdf files with ANN weights are attached ANN-weights.zip

[adcroft]

I've made some suggestions in anticipation of what feedback this would get on dev/gfdl.

[Pperezhogin]

Hi @adcroft. Thanks for the comments.

All suggestions are incorporated. Regression did not change. New MOM_override reads:

#override USE_ZB2020 = True
#override ZB2020_USE_ANN = True
#override USE_CIRCULATION_IN_HORVISC = True
#override ZB2020_ANN_FILE_TALL = /path/to/ocean3d/subfilter/FGR3/EXP1/model/Tall.nc

[adcroft]

Looks good to me