sediment.in

Sediment Model Input Script - sediment.in

The sediment.in file sets the parameters for sediment output. The name of this file is set by the SPARNAM keyword in the ocean.in file. This standard input ASCII file is organized in several sections as shown below, with links to more detailed explanation where required.

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

Notice: A default sediment.in input script is provided in the User/External subdirectory. Also there are several sediment input scripts in the ROMS/External subdirectory which are used in the distributed test cases. They are usually named sediment_app.in where app is the lowercase of the test case CPP option.

Sediment Model Control Switches

• Switch is used to control sediment model computation within nested and/or multiple connected grids, [1:Ngrids] values are expected.
  Lsediment == T

General Sediment Bed Model Controls

• Depositional bed layer thickness (m) criteria to create a new layer. If deposition exceeds this value, then a new layer is created, [1:Ngrids] values are expected.
  NEWLAYER_THICK == 0.01d0

• Bed load transport rate coefficient, [1:Ngrids] values are expected.
  BEDLOAD_COEFF == 0.05d0

Lateral Open Boundary Conditions Parameters

• The lateral boundary conditions are entered with a keyword. A value is expected for each boundary segment per nested grid for each state variable. The sediment tracer variables (cohesive and non-cohesive) require [1:4,1:NCS+NNS,Ngrids] values. If specifying every tracer, enter first 1:NCS cohesive sediment entries followed by 1:NNS non-cohesive sediment entries. The boundary order is: 1=west, 2=south, 3=east, and 4=north. That is, anticlockwise starting at the western boundary.
  
  The keyword is case insensitive and usually has three characters. However, it is possible to have compound keywords, if applicable. For example, the keyword RadNud implies radiation boundary condition with nudging. This combination is usually used in active/passive radiation conditions.
  
  Notice: It is possible to specify the lateral boundary conditions for all biological tracers in a compact form with a single entry. If so, all the biological tracers are assumed to have the same boundary condition as the single entry.
  ! Keyword Lateral Boundary Condition Type
  !
  ! Cla Clamped _____N_____ j=Mm
  ! Clo Closed | 4 |
  ! Gra Gradient | |
  ! Nes Nested 1 W E 3
  ! Nud Nudging | |
  ! Per Periodic |_____S_____|
  ! Rad Radiation 2 j=1
  ! i=1 i=Lm
  ! W S E N
  ! e o a o
  ! s u s r
  ! t t t t
  ! h h
  !
  ! 1 2 3 4
  
  LBC(isTvar) == Per Clo Per Clo  ! idsed(:), compact

• Adjoint-based algorithms can have different lateral boundary conditions keywords.
  ad_LBC(isTvar) == Per Clo Per Clo  ! idsed(:), compact

Suspended Cohesive Sediment Parameters

There are NCS cohesive (mud) sediment tracers per nested grid in ROMS. Therefore, [1:NCS,1:Ngrids] values are expected for these parameters.

• Median sediment grain diameter (mm).
  MUD_SD50 == 0.01d0 0.005d0

• Sediment concentration (kg/m³).
  MUD_CSED == 0.0d0 10.0d0

• Sediment grain density (kg/m³).
  MUD_SRHO == 2650.0d0 2400.0d0

• Particle settling velocity (mm/s).
  MUD_WSED == 0.1d0 0.01d0

• Surface erosion rate (kg/m²/s).
  MUD_ERATE == 5.0d-4 5.0d-4

• Critical shear for erosion and deposition (N/m²).
  MUD_TAU_CE == 0.1d0 0.1d0
  MUD_TAU_CD == 0.1d0 0.1d0

• Porosity (nondimensional): Vwater/(Vwater+Vsed). Its values range between 0 and 1.
  MUD_POROS == 0.9d0 0.9d0

• Lateral, constant, harmonic/biharmonic horizontal diffusion of tracer for the nonlinear model and adjoint-based algorithms.
  MUD_TNU2 == 0.0d0 0.0d0  ! m²/s
  MUD_TNU4 == 0.0d0 0.0d0  ! m⁴/s
  
  ad_MUD_TNU2 == 0.0d0 0.0d0  ! m²/s
  ad_MUD_TNU4 == 0.0d0 0.0d0  ! m⁴/s

• Vertical mixing coefficients for tracers in nonlinear model and basic state scale factor in adjoint-based algorithms.
  MUD_AKT_BAK == 5.0d-6 5.0d-6  ! m²/s
  MUD_AKT_fac == 2*1.0d0  ! nondimensional

• Nudging/relaxation time scales, inverse scales will be computed internally.
  MUD_TNUDG == 0.0d0 0.0d0  ! days

• Morphological time scale factor (greater than or equal to 1.0). A value of 1.0 has no scale effect.
  MUD_MORPH_FAC == 1.0d0 1.0d0  ! nondimensional

• Logical switch to specify which variables to consider on tracers point Sources/Sinks (like river runoff).

MUD_Ltracer == F F

• Logical switches to activate writing of cohesive sediment into output history file.

Hout(idmud) == T  ! mud_01, ... suspended concentration
Hout(iMfrac) == T  ! mudfrac_01, ... bed layer fraction
Hout(iMmass) == T  ! mudmass_01, ... bed layer mass
Hout(iMUbld) == T  ! bedload_Umud_01, ... bed load at U-points
Hout(iMVbld) == T  ! bedload_Vmud_01, ... bed load at V-points

• Logical switches to activate writing of time-averaged, cohesive sediment fields into averages output file.

Aout(idmud) == T  ! mud_01, ... suspended concentration
Aout(iMUbld) == T  ! bedload_Umud_01, ... bed load at U-points
Aout(iMVbld) == T  ! bedload_Vmud_01, ... bed load at V-points

• Logical switches to activate writing of time-averaged, cohesive sediment diagnostic terms into output diagnostics file.

Dout(MTrate) == T  ! mud_01_rate, ... time rate of change
Dout(MThadv) == T  ! mud_01_hadv, ... horizontal total advection
Dout(MTxadv) == T  ! mud_01_xadv, ... horizontal XI-advection
Dout(MTyadv) == T  ! mud_01_yadv, ... horizontal ETA-advection
Dout(MTvadv) == T  ! mud_01_vadv, ... vertical advection
Dout(MThdif) == T  ! mud_01_hdiff, ... horizontal total diffusion
Dout(MTxdif) == T  ! mud_01_xdiff, ... horizontal XI-diffusion
Dout(MTydif) == T  ! mud_01_ydiff, ... horizontal ETA-diffusion
Dout(MTsdif) == T  ! mud_01_sdiff, ... horizontal S-diffusion
Dout(MTvdif) == T  ! mud_01_vdiff, ... vertical diffusion

Non-cohesive Sediment Parameters

There are NNS non-cohesive (sand) sediment tracers per nested grid in ROMS. Therefore, [1:NNS,1:Ngrids] values are expected for these parameters.

• Median sediment grain diameter (mm).
  SAND_SD50 == 1.0d0

• Sediment concentration (kg/m³).
  SAND_CSED == 0.0d0

• Sediment grain density (kg/m³).
  SAND_SRHO == 2650.0d0

• Particle settling velocity (mm/s).
  SAND_WSED == 1.0d0

• Surface erosion rate (kg/m²/s).
  SAND_ERATE == 5.0d-4

• Critical shear for erosion and deposition (N/m²).
  SAND_TAU_CE == 0.1d0
  SAND_TAU_CD == 0.1d0

• Porosity (nondimensional): Vwater/(Vwater+Vsed). Its values range between 0 and 1.
  SAND_POROS == 0.5d0

• Lateral, constant, harmonic/biharmonic horizontal diffusion of tracer for the nonlinear model and adjoint-based algorithms.
  SAND_TNU2 == 0.0d0  ! m²/s
  SAND_TNU4 == 0.0d0  ! m⁴/s
  
  ad_SAND_TNU2 == 0.0d0  ! m²/s
  ad_SAND_TNU4 == 0.0d0  ! m⁴/s

• Vertical mixing coefficients for tracers in nonlinear model and basic state scale factor in adjoint-based algorithms.
  SAND_AKT_BAK == 5.0d-6  ! m²/s
  SAND_AKT_fac == 1.0d0  ! nondimensional

• Nudging/relaxation time scales, inverse scales will be computed internally.
  SAND_TNUDG == 0.0d0  ! days

• Morphological time scale factor (greater than or equal to 1.0). A value of 1.0 has no scale effect.
  SAND_MORPH_FAC == 1.0d0  ! nondimensional

• Logical switch to specify which variables to consider on tracers point Sources/Sinks (like river runoff).
  SAND_Ltracer == F

• Logical switches to activate writing of non-cohesive sediment into output history file.

Hout(idsand) == T  ! sand_01, ... suspended concentration
Hout(iSfrac) == T  ! sandfrac_01, ... bed layer fraction
Hout(iSmass) == T  ! sandmass_01, ... bed layer mass
Hout(iSUbld) == T  ! bedload_Usand_01, ... bed load at U-points
Hout(iSVbld) == T  ! bedload_Vsand_01, ... bed load at V-points

• Logical switches to activate writing of time-averaged, non-cohesive sediment fields into averages output file.

Aout(idsand) == T  ! sand_01, ... suspended concentration
Aout(iSUbld) == T  ! bedload_Usand_01, ... bed load at U-points
Aout(iSVbld) == T  ! bedload_Vsand_01, ... bed load at V-points

• Logical switches to activate writing of time-averaged, non-cohesive sediment diagnostic terms into output diagnostics file.

Dout(STrate) == T  ! sand_01_rate, ... time rate of change
Dout(SThadv) == T  ! sand_01_hadv, ... horizontal total advection
Dout(STxadv) == T  ! sand_01_xadv, ... horizontal XI-advection
Dout(STyadv) == T  ! sand_01_yadv, ... horizontal ETA-advection
Dout(STvadv) == T  ! sand_01_vadv, ... vertical advection
Dout(SThdif) == T  ! sand_01_hdiff, ... horizontal total diffusion
Dout(STxdif) == T  ! sand_01_xdiff, ... horizontal XI-diffusion
Dout(STydif) == T  ! sand_01_ydiff, ... horizontal ETA-diffusion
Dout(STsdif) == T  ! sand_01_sdiff, ... horizontal S-diffusion
Dout(STvdif) == T  ! sand_01_vdiff, ... vertical diffusion

Bed Layer and Bottom Sediment Parameters

• Logical switches to activate writing of bed layer and bottom sediment fields into output NetCDF file(s), [1:Ngrids] values are expected.

Hout(ithck) == T  ! bed_thickness sediment layer thickness
Hout(iaged) == T  ! bed_age sediment layer age
Hout(iporo) == T  ! bed_porosity sediment layer porosity
Hout(idiff) == F  ! bed_biodiff biodiffusivity