Land Model

LandModel{PS, S, SRC, IS} <: BalanceLaw

A BalanceLaw for land modeling. Users may over-ride prescribed default values for each field.

Usage

LandModel(
    param_set,
    soil,
    source
    init_state_prognostic
)

Fields

• param_set

  Parameter set

• soil

  Soil model

• source

  Source Terms (Problem specific source terms)

• init_state_prognostic

  Initial Condition (Function to assign initial values of state variables)

SoilModel{PF, W, H} <: BalanceLaw

A BalanceLaw for soil modeling. Users may over-ride prescribed default values for each field.

Usage

SoilModel(
    param_functions,
    water,
    heat,
)

Fields

• param_functions

  Soil Parameter Functions

• water

  Water model

• heat

  Heat model

SoilWaterModel{FT, IF, VF, MF, HM, Fiϑl, Fiθi, BCD, BCN} <: AbstractWaterModel

The necessary components for solving the equations for water (liquid or ice) in soil.

Without freeze/thaw source terms added (separately), this model reduces to Richard's equation for liquid water. Note that the default for θ_i is zero. Without freeze/thaw source terms added to both the liquid and ice equations, the default should never be changed, because we do not enforce that the total volumetric water fraction is less than or equal to porosity otherwise.

When freeze/thaw source terms are included, this model encompasses water in both liquid and ice form, and water content is conserved upon phase change.

Fields

• impedance_factor

  Impedance Factor - will be 1 or ice dependent

• viscosity_factor

  Viscosity Factor - will be 1 or temperature dependent

• moisture_factor

  Moisture Factor - will be 1 or moisture dependent

• hydraulics

  Hydraulics Model - used in matric potential and moisture factor of hydraulic conductivity

• initialϑ_l

  Initial condition: augmented liquid fraction

• initialθ_i

  Initial condition: volumetric ice fraction

• dirichlet_bc

  Dirichlet boundary condition structure

• neumann_bc

  Neumann boundary condition structure

PrescribedWaterModel{F1, F2} <: AbstractWaterModel

Model structure for a prescribed water content model.

The user supplies functions of space and time for both ϑ_l and θ_i. No auxiliary or state variables are added, no PDE is solved. The defaults are no moisture anywhere, for all time.

Fields

• ϑ_l

  Augmented liquid fraction

• θ_i

  Volumetric fraction of ice

SoilHeatModel{FT, FiT, BCD, BCN} <: AbstractHeatModel

The necessary components for the Heat Equation in a soil water matrix.

Fields

• initialT

  Initial conditions for temperature

• dirichlet_bc

  Dirichlet BC structure

• neumann_bc

  Neumann BC structure

PrescribedTemperatureModel{F1} <: AbstractHeatModel

Model structure for a prescribed temperature model.

SoilWaterParameterizations

van Genuchten, Brooks and Corey, and Haverkamp parameters for and formulation of

• hydraulic conductivity
• matric potential

Hydraulic conductivity can be chosen to be dependent or independent of impedance, viscosity and moisture.

Functions for hydraulic head, effective saturation, pressure head, matric potential, and the relationship between augmented liquid fraction and liquid fraction are also included.

SoilHeatParameterizations

Functions for volumetric heat capacity, temperature as a function of volumetric internal energy, saturated thermal conductivity, thermal conductivity, relative saturation and the Kersten number are included. Heat capacities denoted by ρc_ are volumetric, while cp_ denotes an isobaric specific heat capacity.

SoilParamFunctions{FT} <: AbstractSoilParameterFunctions{FT}

Necessary parameters for the soil model. These will eventually be prescribed functions of space (and time).

Fields

• porosity

  Aggregate porosity of the soil

• Ksat

  Hydraulic conductivity at saturation. Units of m s-1.

• S_s

  Specific storage of the soil. Units of m s-1.

• ν_ss_gravel

  Volume fraction of gravels, relative to soil solids only. Units of m-3 m-3.

• ν_ss_om

  Volume fraction of SOM, relative to soil solids only. Units of m-3 m-3.

• ν_ss_quartz

  Volume fraction of quartz, relative to soil solids only. Units of m-3 m-3.

• ρc_ds

  Bulk volumetric heat capacity of dry soil. Units of J m-3 K-1.

• ρp

  Particle density for soil solids. Units of kg/m^3

• κ_solid

  Thermal conductivity of the soil solids. Units of W m-1 K-1.

• κ_sat_unfrozen

  Saturated thermal conductivity for unfrozen soil. Units of W m-1 K-1.

• κ_sat_frozen

  Saturated thermal conductivity for frozen soil. Units of W m-1 K-1.

• a

  Adjustable scale parameter for determining Kersten number in the Balland and Arp formulation; unitless.

• b

  Adjustable scale parameter for determining Kersten number in the Balland and Arp formulation; unitless.

• κ_dry_parameter

  Parameter used in the Balland and Arp formulation for κ_dry; unitless

get_water_content(
    water::SoilWaterModel,
    aux::Vars,
    state::Vars,
    t::Real
)

Return the moisture variables for the balance law soil water model.

get_water_content(
    water::PrescribedWaterModel,
    aux::Vars,
    state::Vars,
    t::Real
)

Return the moisture variables for the prescribed soil water model.

struct Dirichlet{Fs, Fb} <: AbstractBoundaryFunctions

A concrete type to hold the surface state and bottom state variable values/functions, if Dirichlet boundary conditions are desired.

Fields

• surface_state

  Surface state boundary condition

• bottom_state

  Bottom state boundary condition

struct Neumann{Fs, Fb} <: AbstractBoundaryFunctions

A concrete type to hold the surface and/or bottom diffusive flux values/functions, if Neumann boundary conditions are desired.

Note that these are intended to be scalar values. In the boundary_state! functions, they are multiplied by the ẑ vector (i.e. the normal vector n̂ to the domain at the upper boundary, and -n̂ at the lower boundary. These normal vectors point out of the domain.)

Fields

• surface_flux

  Surface flux boundary condition

• bottom_flux

  Bottom flux boundary condition