npzd Franks.in

Franks NPZD Biological Model Input Script - npzd_Franks.in

The npzd_Franks.in file sets the parameters for the Franks et al. NPZD model. The name of this file is set by the BPARNAM keyword in the ocean.in file. A default npzd_Franks.in standard input ASCII file can be found in the User/External subdirectory of the ROMS source code. In order to include the Franks et al. NPZD model in ROMS you must set BPARNAM correctly and activate the NPZD_FRANKS CPP option.

The Franks NPZD model equations and representative parameters may be found in:

• Franks et al. 1986a

Notice: Detailed information about ROMS input script file syntax can be found here.

Biological Model Parameters

Input parameter units are specified within brackets ([ ])and default values are specified within braces ({ }).

• This switch to control the computation of npzd_Franks within nested and/or multiple connected grids. By default this switch is set to TRUE in mod_scalars.F for all grids. Ngrids values are expected. The user has the option, for example, to compute the biology in just one of the nested grids. If so, this switch needs to be consistent with the dimension parameter NBT in mod_param.F. In order to make the model more efficient in memory usage, NBT(:) should be zero in such grids.

Lbiology == T

• Maximum number of iterations to achieve convergence of the nonlinear solution.

BioIter == 1

• Initial concentration for analytical uniform initial conditions, [millimole/m³]. It is only used when ANA_BIOLOGY is activated.

BioIni(iNO3_) == 1.67d0  ! nitrate
BioIni(iPhyt) == 0.08d0  ! phytoplankton
BioIni(iZoop) == 0.06d0  ! zooplankton
BioIni(iSDet) == 0.04d0  ! detritus

• Light extinction coefficient, [1/m], {0.067}.

K_ext == 0.06d0

• Inverse half-saturation for phytoplankton nitrate uptake [1/(millimole_N m^-3)], {1.0d0}.

K_NO3 == 0.1d0

• Phytoplankton saturation coefficient, [millimole_N m^-3], {0.4d0}.

K_Phy == 0.4d0

• Nitrate uptake rate, [1/day], {1.5d0}.

Vm_NO3 == 2.0d0

• Phytoplankton senescence/mortality rate, [1/day], {0.1d0}.

PhyMR == 0.05d0

• Zooplankton maximum growth rate, [1/day], {0.52}.

ZooGR == 0.6d0

• Zooplankton mortality rate, [1/day], {0.145d0}.

ZooMR == 0.2d0

• Zooplankton death bits rate, [1/day], {0.05d0}.

ZooMD == 0.05d0

• Zooplankton grazing inefficiency, [nondimensional], {0.3d0}.

ZooGA == 0.3d0

• Zooplankton excreted fraction, [nondimensional], {0.15d0}.

ZooEC == 0.15d0

• Detritus remineralization rate, [1/day], {0.1d0}.

DetRR == 0.1d0

• Detrital sinking rate, [m/day], {8.0d0}.

wDet == 5.0d0

• Lateral, constant, harmonic/biharmonic horizontal diffusion of biological tracer for nonlinear model and adjoint-based algorithms: [1:NBT,Ngrids] values expected.

TNU2 == 4*0.0d0  ! m²/s
TNU4 == 4*0.0d0  ! m⁴/s

ad_TNU2 == 4*0.0d0  ! m²/s
ad_TNU4 == 4*0.0d0  ! m⁴/s

• Vertical mixing coefficients for biological tracers: [1:NBT,Ngrids] values expected.

AKT_BAK == 4*1.0d-6  ! m²/s

ad_AKT_fac == 4*1.0d0  ! nondimensional

• Nudging/relaxation time scales, inverse scales will be computed internally: [1:NBT,Ngrids] values expected.

TNUDG == 4*0.0d0  ! days

• Logical switches to specify which variables to consider on tracers point Sources/Sinks (like river runoff): [1:NBT,Ngrids] values expected.

LtracerSrc == 4*F

• Logical switches to activate writing of biological tracers into history/average output file: [1:NBT,Ngrids] values expected.

Hout(idTvar) == 4*T  ! biological tracer
Hout(idTsur) == 4*F  ! surface tracer flux

! idTvar(idbio(1))=iNO3_ Nitrate concentration
! idTvar(idbio(2))=iPhyt Phytoplankton biomass
! idTvar(idbio(3))=iZoop Zooplankton biomass
! idTvar(idbio(4))=iSdet Detritus concentration