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Model variables
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Model variables are defined in .h Fortran 77 files :

Domain variables (*grid.h*)
===========================

**grid.h** : Environmental two-dimensional arrays associated with curvilinear horizontal coordinate system 

| h       : Model topography (bottom depth [m] at RHO-points.)
| dh      : Topograhy increment in case of moving bathymetry 
| f       : Coriolis parameter [1/s].
| fomn    : Compound term, f/[pm*pn] at RHO points.

| angler  : Angle [radians] between XI-axis and the direction to the EAST at RHO-points.
|
| latr    : Latitude (degrees_north) at RHO-, U-, and V-points.
| latu
| latv
| lonr    : Longitude (degrees_east) at RHO-, U-, and V-points.
| lonu
| lonv

| xp      : XI-coordinates [m] at PSI-points.
| xr      : XI-coordinates [m] at RHO-points.
| yp      : ETA-coordinates [m] at PSI-points.
| yr      : ETA-coordinates [m] at RHO-points.

| pm      : Coordinate transformation metric "m" [1/meters] associated with the differential distances in XI.
| pn      : Coordinate transformation metric "n" [1/meters]associated with the differential distances in ETA.
| om_u    : Grid spacing [meters] in the XI -direction at U-points.
| om_v    : Grid spacing [meters] in the XI -direction at V-points.
| on_u    : Grid spacing [meters] in the ETA-direction at U-points.
| on_v    : Grid spacing [meters] in the ETA-direction at V-points.

| dmde    : ETA-derivative of inverse metric factor "m", d(1/M)/d(ETA).
| dndx    : XI-derivative  of inverse metric factor "n", d(1/N)/d(XI).

| pmon_p  : Compound term, pm/pn at PSI-points.
| pmon_r  : Compound term, pm/pn at RHO-points.
| pmon_u  : Compound term, pm/pn at U-points.
| pnom_p  : Compound term, pn/pm at PSI-points.
| pnom_r  : Compound term, pn/pm at RHO-points.
| pnom_v  : Compound term, pn/pm at V-points.

| rmask   : Land-sea masking arrays at RHO-,U-,V- and PSI-points (rmask,umask,vmask) = (0=Land, 1=Sea)
| umask   
| vmask
| pmask   : pmask=(0=Land, 1=Sea, 1-gamma2 =boundary).

| reducu  : reduction coefficient along x-axis for rivers sections  
| reducv  : reduction coefficient along y-axis for rivers sections


Barotropic variables (*ocean2d.h*)
===================================

**ocean2d.h** : 2D dynamical variables for fast mode

| zeta,rzeta   :  Free surface elevation [m] and its time tendency;
| ubar,rubar   :  Vertically integrated  2D velocity components in
| vbar,rvbar   :  XI- and ETA-directions and their time tendencies;


Tri-dimensionnal variables (*ocean3d.h*)
========================================

**ocean3d.h** : 3D tracers dynamical variables for baroclinic mode

| u,v  : 3D velocity components in XI- and ETA-directions 
| t : tracer array (temperature, salinity, passive tracers, sediment)
| Hz : level thickness
| z_r : depth at rho point
| z_w : depth at w point
| Huon : transport a U point
| Hvon : transport at V point
| We, Wi : vertical velocity (explicit, implicit)
| rho : density anomaly
| rho1 :  potential density at 1 atm 

Surface forcing (forces.h)
==========================

**forces.h** : 

*Surface momemtum flux (wind stress) :*

| sustr :  XI- and ETA-components of kinematic surface momentum flux
| svstr :  wind stresses) defined at horizontal U- and V-points.dimensioned as [m^2/s^2].


*Bottom mometum flux :*

| bustr : XI- and ETA-components of kinematic bottom momentum flux
| bvstr : (drag) defined at horizontal U- and V-points [m^2/s^2].!


*Surface tracers fluxes :*

| stflx  : Kinematic surface fluxes of tracer type variables at horizontal RHO-points. Physical dimensions [degC m/s] - temperature; [PSU m/s] - salinity.
| dqdt   :  Kinematic surface net heat flux sensitivity to SST [m/s].
| sst   :   Current sea surface temperature [degree Celsius].
| dqdtg :  Two-time-level grided data for net surface heat flux
| sstg  :  sensitivity to SST grided data [Watts/m^2/Celsius] and sea surface temperature [degree Celsius].
| dqdtp :  Two-time-level point data for net surface heat flux
| sstp  :  sensitivity to SST grided data [Watts/m^2/Celsius] and  sea surface temperature [degree Celsius].
| tsst  :   Time of sea surface temperature data.
| sss   :   Current sea surface salinity [PSU].
| tair  :   surface air temperature at 2m [degree Celsius].
| wsp   :   wind speed at 10m [degree Celsius].
| rhum  :   surface air relative humidity 2m [fraction]
| prate  :  surface precipitation rate [cm day-1]
| radlw  :  net terrestrial longwave radiation [Watts meter-2]
| radsw  :  net solar shortwave radiation [Watts meter-2]
| patm2d :  atmospheric pressure above mean seal level
| paref  :   reference pressure to compute inverse barometer effect
| srflx : Kinematic surface shortwave solar radiation flux [degC m/s] at horizontal RHO-points

*Wind induced waves everything is defined at rho-point :*

| wfrq : wind-induced wave frequency [rad/s]
| uorb : xi-component  of wave-induced bed orbital velocity [m/s]
| vorb : eta-component of wave-induced bed orbital velocity [m/s]
| wdrx : cosine of wave direction [non dimension]
| wdre : sine of   wave direction [non dimension]
| whrm : (RMS) wave height (twice the wave amplitude) [m]
| wepb : breaking dissipation rate (\epsilon_b term) [m3/s3]
| wepd : frictional dissipation rate (\epsilon_d term) [m3/s3]
| wepr :roller dissipation rate (\epsilon_r term) [m3/s3]
| wbst : frictional dissipation stress (e_d k/sigma) [m2/s2]

*Wave averaged quantities :*

|  brk2dx   :   xi-direciton 2D breaking dissipation (rho)
|  brk2de   :  eta-direction 2D breaking dissipation (rho)
|  frc2dx   :   xi-direciton 2D frictional dissipation (rho)
|  frc2de   :  eta-direction 2D frictional dissipation (rho)
|  ust2d    :   xi-direciton Stokes transport (u-point)
|  vst2d    :  eta-direciton Stokes transport (v-point)
|  sup      :  quasi-static wave set-up (rho-point)
|  calP     :  pressure correction term (rho-point)
|  Kapsrf   :  Bernoulli head terrm at the surface (rho-point)
|  brk3dx   :   xi-direciton 3D breaking dissipation (rho)
|  brk3de   :  eta-direction 3D breaking dissipation (rho)
|  ust      :   xi-direciton 3D Stokes drift velocity (u-point)
|  vst      :  eta-direciton 3D Stokes drift velocity (v-point)
|  wst      :       vertical 3D Stokes drift velocity (rho-point)
|  Kappa    :  3D Bernoulli head term (rho-point)
|  kvf      :  vertical vortex force term (K term, 3D, rho-point)
|  Akb      :  breaking-wave-induced additional diffusivity (w-point)
|  Akw      :  wave-induced additional diffusivity (rho-point)
|  E_pre    :  previous time-step value for Akw estimation (rho)
|  frc3dx   :   xi-direciton 3D frictional dissipation (rho)
|  frc3de   :  eta-direction 3D frictional dissipation (rho)