Property:Describe key physical parameters
From CSDMS
This is a property of type Text.
M
Bedrock erodibility, mass wasting diffusivity, bed material grain size, flow hydrologic parameters, relative evaporation rate, cratering size distribution and rate, eolian deposition parameters, etc. +
G
Boussinesq aquifer equation, Darcy's law. +
Breaking wave conditions are estimated from input wave information using linear wave theory. Longshore sand transport rates are estimated using a modified version of the CERC equation and the equation governing shoreline change is formulated by conservation of sand volume. +
B
S
CERC formula for sediment transport rate (see Komar)
Kamphuis formula for sediment transport rate.
Conservation of sediment mass. +
C
P
Calculate the hypsometric integral by
HI = (Zbar-Zo)/(Zmax-Zo)
where Zbar is the average elevation of the contributing area to a pixel
Zo is the local elevation (the elevation of a pixel)
Zmax is the maximum elevation of a pixel contributing area.
For more details read:
Cohen, S., G. Willgoose, and G. Hancock (2008), A methodology for calculating the spatial distribution of the area-slope equation and the hypsometric integral within a catchment, Journal of Geophysical Research, 113, F03027. +
C
Cosmogenic nuclide production decay with depth. Power-law distribution of landslide size. Calculates a fluvial storage reservoir. +
M
Creep coefficient for mud
Creep coefficient for marsh peat
Tidal dispersion coefficient
Erosion coefficient
Critical shear stress for vegetated areas
Critical shear stress for unvegetated areas
Increase in τcr with depth below MLW
Settling velocity in unvegetated areas
Settling velocity in vegetated areas
Tidal range
Tidal period
External sediment supply
Rate of relative sea level rise
Manning coefficient for unvegetated mud
Manning coefficient for vegetated areas
Maximum organic accretion rate
Sediment dry bulk density
Morphological time step
Spatial resolution
v2.0 also includes:
Time series of wind speed and direction
Edge erodibility
Fraction of eroded edge material that is oxidized (i.e., removed from the mass balance)
Rate of pond deepening
Rate of pond expansion
Elevation thresholds for pond formation +
D
Croley, T. E., II, and He, C. (2005). “Distributed-parameter large basin runoff model. I: Model development.” J. Hydrol. Eng., 10(3), 173–181. +
B
Current speed, temperature, salinity, sea surface elevation, wind speed, river fluxes.
Based on Navier Stokes equations, Boussinesq approximation, terrain following coordinates (sigma) +
S
A
D
Drainage density is calculated as the inverse of the minimum distance to channel averaged over all nodes in the Landlab domain. +
S
T
S
W
T
Equations Used by the 1D Richards' Equation Method
v = K * (1 - ψ_z) = Darcy's Law for vertical flow rate (m / s)
v_z = J - θ_t = conservation of mass, with source/sink term J
Θ_e = (θ - θ_r) / (θ_s - θ_r) = effective saturation or scaled water content (unitless)
θ_r = θ_s ( abs(ψ_B) / 10000)^λ = residual water content (unitless)
K = K_s * Θ_e^η/λ = hydraulic conductivity (m / s) (see Notes below)
ψ = ψ_B (Θ_e^-c/λ - 1)^1/c - ψ_A = pressure head (meters) (see Notes below)
These equations are used to compute the time evolution of 1D (vertical, subsurface) profiles for (1) soil moisture, θ, (2) pressure head, ψ, (3) hydraulic conductivity, K and (4) vertical flow rate, v. TopoFlow solves these equations separately to get time-evolving profiles for every grid cell in a DEM. The result is a 3D grid for each of these four variables that spans the unsaturated zone. The third equation above just defines a variable that is used in the 4th and 5th equations, so the coupled set constitutes 4 equations to be solved for 4 unknowns. These equations can be combined into one nonlinear, parabolic, second-order PDE (partial differential equation) known as the one-dimensional Richards' equation. +
