1. Governing Equations¶

Related CPP options:

SOLVE3D	solve 3D primitive equations
UV_COR	Activate Coriolis terms
UV_ADV	Activate advection terms
NBQ	Activate non-boussinesq option
CROCO_QH	Activate quasi-hydrostatique option
MRL_WCI	Activate wave-current interactions

Preselected options:

# define SOLVE3D
# define UV_COR
# define UV_ADV
# undef  NBQ
# undef  CROCO_QH
# undef  MRL_WCI

Presentation

By default (#undef NBQ), CROCO solves the primitive equations as in ROMS, from which it inherited the robustness and efficiency of its time-splitting implementation (Shchepetkin & McWilliams, 2005; Debreu et al., 2012) and the NBQ option proposes an extension for nonhydrostatic applications. In CROCO’s time-splitting algorithm, the ”slow mode” is similar to ROMS internal (baroclinic) mode described in Shchepetkin & McWilliams (2005), whereas, the ”fast mode” can include, in addition to the external (barotropic) mode, the pseudo-acoustic mode that allows computation of the nonhydrostatic pressure within a non-Boussinesq approach (Auclair et al., 2018). In this case, the slow internal mode is also augmented by a prognostic equation of vertical velocity, replacing the hydrostatic equation. Another option (CROCO_QH) extends the PE equations to form the quasi-hydrostatic equations, relaxing the hypothesis of weak horizontal Coriolis force (Marshall et al., 1997), thus adding a nonhydrostatic pressure component that is solved diagnostically. Then another option (MRL_WCI) treats the wave-averaged equations (McWilliams et al., 2004) with wave-current interaction terms that are both conservative and non-conservative (needing parametrizations).