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Parameters for various processes
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LMDz-SACS takes into account various processes: the chemistry, the physics, the convection including or not some thermals. A number of choices are available to the user. See :doc:`LMDz-Dispersion-SACS plugin</documentation/plugins/models/lmdz>` for information on how these are done in the yaml.

physic
-------
If True, the simulation takes into account the physics i.e. reads the variables provided in :doc:`phystoke<pstoke>` and use them to enter the physical loop (see :bash:`dyn3d/timeloop.F90`), splitted into nsplit_phy steps, deduced (see :bash:`dyn3d/dispersion.F90` from the splitting provided in :doc:`totinput<totinput>`. The physical step in mainly integrated in :bash:`phylmd/phytrac.F90` and includes the chemistry with the sources and sinks, the thermals (if relevant), the convection (according to the chosen scheme) and the boundary layer (parameterized by the mixing coefficient :bash:`coefh` read in phystoke.nc).

Thermals
---------
Depend on the convection scheme.

Convection
-----------
Three convection schemes are available:
 - Tiedke: :bash:`flag_con=2`
 - Kerry-Emmanuel: :bash:`flag_con=3`
 - Kerry-Emmanuel with thermics: :bash:`flag_con=30`

The choice of the scheme is specified in :doc:`totinput<totinput>`.

do_chemistry
------------
if True (choice specified in :doc:`totinput<totinput>`), the simulation takes into account the chemistry, as specified by the chemical scheme.
It requires to:

  1) read the scaling factors for the prescribed species if any in file :doc:`mod_scale_SPEC.bin<chemistry>`, the production/loss fields if any in file :doc:`mod_prodscale_SPEC.bin<chemistry>` (see :bash:`dyn3d/dispersion.F90`)
  2) read the deposition velocities if any in :doc:`dep_SPEC.nc<chemistry>` (see :bash:`readsdepvel` called by :bash:`dyn3d/dispersion.F90`)
  3) read the chemical fields in :bash:`dyn3d/readchem.F90`, called by :bash:`dispersion.F90` (initialization) and :bash:`timeloop.F90` (each time step :bash:`itau` within each day): photolysis rates, associated temperature and pressure in :doc:`kinetic.nc<chemistry>`, prescribed fields for the prescribed species if any in file :doc:`prescr_SPEC.nc<chemistry>`, production/loss fields if any in file :doc:`prodloss_SPEC.nc<chemistry>`.
  4) compute the actual chemical production and loss in :bash:`comp_chemistry` from :bash:`phylmd/comp_chemistry.F90`, called by :bash:`phylmd/phytrac.F90`.