Diagnoses in MARS

Momentum equation

To save the different terms of the momentum equations, add the cpp keys -Dkey_diagdyn.

Optional : add -Dkey_diagdyn_details to get the different terms of non-linear and diffusion terms.

Description of the different terms

The momentum equation can be written as:

\(\nu_Si=\nu_{Simax} \frac{Si}{K_{Sipsnz}+Si}\)

avec

: \(\nu_Si\) = PLUS TARD

\(\nu_{Simax}\) = Vitesse max d’absorption de Si par Pseuso Nitzschia (p_psnz_vmaxSi) \(K_{Sipsnz}\) = Constante de Michaelis de Pseudo Nitzschia pour la croissance (p_psnz_kSi)

The variables are saved in the output file (diag_suffix.nc) and named as follow (at u location)

Coriolis term                  cor2_x : -f*v
Non linear advection           nlt_x_ududx : udu/dx
                               nlt_x_vdudy : vdu/dy
                               nlt_x_wdudz : wdu/dz
Internal pressure gradient
                               ipg_x : 1/rho dPi/dx
External pressure gradient
                               epg_x : - g d ssh / dx - 1/rho d Pa /dx
Vertical diffusion
                               vdif_x : dz(nz*du/dz)/dz
Time trend
                               dudt_x : du/dt

According to the sign of each terms, we must have the following balance:

dudt_x = epg_x - cor2_x + ipg_x + (hdif_x_dnududx2 + hdif_x_dnududy2 + vdif_x) - (nlt_x_ududx + nlt_x_vdudy + nlt_x_wdudz)