Property:Describe processes
From CSDMS
This is a property of type Text.
T
The dynamic wave method for flow routing in the channels of a D8-based river network. +
C
The effects of individual storm events and SLR on shoreface evolution; dune dynamics, including dune growth, erosion, and migration; overwash deposition by individual storms; large-scale coastline evolution arising from alongshore sediment transport processes; and human management activities. +
The four primary components of our multi-physics code include geomechanical, hydrologic, solute transport and heat transfer modules. The geomechanical module calculates displacement of an elastic lithosphere disturbed by an ice sheet load. Transient geomechanical deformation is represented by one-dimensional (lateral) viscous asthenosphere flow. Our geomechanical module is partially coupled to the hydrologic module by providing the rate of change in the mean normal stress. Mean normal stress change rate is included as a source term in the groundwater flow equation driving flow. Flow is also influenced by changes in the top specified hydraulic head boundary condition. We implement two-way coupling between fluid flow, solute transport and heat transfer module via density and viscosity equations of state.
Three additional modules in our multi-physics code calculate changes to the upper hydraulic and thermal boundary conditions or alter the hydraulic transport properties (permeability) due to hydrogeomechanical failure. These include ice sheet evolution, permafrost, and failure analysis modules. Ice sheet thickness determines both the vertical load in the geomechanical module as well as the hydraulic head boundary condition at the land surface in the hydrologic module. In this study we adopted a simple parabolic polynomial equation to represent the idealized geometry of an ice sheet’s cross section in the ice sheet evolution module. We solved for permafrost
formation at and below the land surface using a suite of one-dimensional heat transfer models. We allowed for grid growth within the permafrost module to account for changes in ice sheet thickness. A failure analysis module was used to modify permeability due to hydromechanical failure. We adopted the effective Coulomb’s Failure Stress change criterion from Ge et al.(2009) to assess regions of failure during glaciations. +
M
The ground-water flow equation is solved using the finite-difference approximation. The flow region is subdivided into blocks in which the medium properties are assumed to be uniform. In plan view the blocks are made from a grid of mutually perpendicular lines that may be variably spaced. Model layers can have varying thickness. A flow equation is written for each block, called a cell. Several solvers are provided for solving the resulting matrix problem; the user can choose the best solver for the particular problem. Flow-rate and cumulative-volume balances from each type of inflow and outflow are computed for each time step. +
W
The integrated multi-processes include:
# hydrological cycles (evaporation, evapotranspiration, infiltration, and recharges);
# fluid flow (surface runoff in land surface, hydraulics and yydrodynamics in river/stream/canal networks;
# interflow in vadose zones, and groundwater flow in saturated zones);
# salinity transport and thermal transport (in surface waters and groundwater);
# sediment transport (in surface waters);
# water quality transport (any number of reactive constituents);
# biogeochemical cycles (nitrogen, phosphorous, carbon, oxygen, etc.); and
# biota kinetics (algae, phyotoplankton, zooplakton, caliform, bacteria, plants, etc.). +
C
The key processes are 1) topographically-driven overland flow and 2) bedload transport by this flow. Through these processes the model self-organizes channels which incise, back-fill, and avulse. Processes are similar to alluvial fans. There are no marine processes besides bedload dumping. +
T
The kinematic wave method for flow routing in the channels of a D8-based river network. +
R
The main source code calls sub-modules that simulate the following processes:
- Vegetation community colonization as a function of local water depth. Colonization is deterministic over some ranges and stochastic in others.
- Solution of flow field in two dimensions using a cellular automata algorithm (see Larsen and Harvey, 2010, Geomorphology, and Larsen and Harvey, 2010 in press, American Naturalist). The flow field is only simulated during high-flow events that entrain sediment.
- Sediment transport by flow according to an advection-dispersion equation. Within each high-flow pulse, steady conditions are assumed.
- Evolution of the topography through sediment transport, peat accretion (which is based on Larsen et al., Ecological Monographs, 2007), diffusive erosion of topographic gradients, vegetative propagation, and below-ground biomass expansion.
- Adjustment of water levels and high-flow discharge to satisfy a water balance and compensate for the growth of vegetation patches. +
F
The mean annual temperature of the warmest and coldest months at a given location gives a first-order estimate of distribution of permafrost. +
K
The model calculates changes in elevation and vegetation growth for a hypothetical salt marsh. In each cell, elevation change is calculated as the difference between accretion and erosion. Accretion rates are a function of inundation depth, vegetation growth, and suspended sediment concentration. Water routed according to Rinaldo et al. (1999) scheme. Erosion rates calculated according to excess sheer stress. Channels widen according to a diffusion-like routine where downslope transport is inversely proportional to vegetation. Vegetation grows according to Morris et al. (2002) where biomass is proportional to inundation depth up until an optimum depth. Episodic vegetation disturbance is simulated by removing vegetation from randomly selected cells (Kirwan et al., 2008). Another version of the model treats wave erosion in a simplistic manner (Kirwan and Murray, 2008). +
E
The model computes flow accumulation using multiple flow direction over unstructured grids based on + an adaptation of the implicit approach proposed by Richardson & Perron (Richardson, Hill, & Perron, 2014).
+ an extension of the parallel priority-flood depression-filling algorithm from (Barnes, 2016) to unstructured mesh is used to simulate sedimentation in upland areas and internally drained basins.
+ marine sedimentation is based on a diffusion algorithm similar to the technique proposed in pybadlands (Salles, Ding, & Brocard, 2018). +
H
The model consists of subroutines for meteorological interpolation, snow accumulation and melt, evapotranspiration estimation, a soil moisture accounting procedure, routines for runoff generation and finally, a simple routing procedure between subbasins and in lakes. It is possible to run the model separately for several subbasins and then add the contributions from all subbasins. Calibration as well as forecasts can be made for each subbasin. +
D
The model describes the tidal-network initiation and development, and the vertical accretion of the adjacent marsh platform. Tidal network development is driven by the exceedance of a local hydrodynamic bottom shear stress, controlled by water surface gradients. Marsh vertical growth is modeled by using a sediment balance equation acconting for erosion and deposition terms. The deposition terms account for sediment settling, trapping and organic production. +
F
The model is forced by tidal or other barotropic boundary conditions, wind, and/or fixed baroclinic pressure gradient, all acting at a single frequency (including zero) and specified by the user. +
E
The model predicts bankfull geometry of single-thread, sand-bed rivers from first principles, i.e. conservation of channel bed and floodplain sediment, which does not require the a-priori knowledge of the bankfull discharge. Building on previous work on the equilibrium of engineered rivers, i.e. rivers with fixed banks and sinuosity (Blom et al., 2016, 2017, Arkesteijn et al., 2019), as well as formulations for floodplain morphodynamics (Lauer & Parker, 2008, Viparelli et al., 2013, Lauer et al., 2016) and bank migration (Parker et al., 2011, Eke et al., 2014, Davidson & Eaton, 2018, De Rego et al., 2020), we derive equilibrium solutions for channel geometry (width, depth, slope), floodplain sediment size distribution, bankfull discharge, channel migration and overbank deposition rates.
References
Arkesteijn, L., Blom, A., Czapiga, M. J., Chavarrias, V. & Labeur, R. J. (2019). The quasi-equilibrium longitudinal profile in backwater reaches if the engineered alluvial river: A space-marching method, Journal of Geophysical Research: Earth Surface 124, 2542-2560.
Blom, A., Viparelli, E. & Chavarrias, V. (2016). The graded alluvial river: Profile concavity and downstream fining, Geophysical Research Letters 43 (12), 6285-6293.
Blom, A., Arkesteijn, L., Chavarrias, V. & Viparelli, E. (2017). The equilibrium alluvial river under variable flow and its channel-forming discharge, Journal of Geophysical Research: Earth Surface 122, 1924-1948.
Davidson, S.L. & Eaton, B. C. (2018). Beyond Regime: A stochastic model of floods, bank erosion, and channel migration. Water Resources Research, 54, 6282-6298.
De Rego, K., Lauer, J. W., Eaton, B. & Hassan, M. (2020). A decadal-scale numerical model for wandering, cobble-bedded rivers subject to disturbance, Earth Surface Processes and Landforms 45, 912-927.
Eke, E., Parker, G. & Shimizu, Y. (2014). Numerical modeling of erosional and depositional bank processes in migrating river bends with self-formed width: Morphodynamics of bar push and bank pull, Journal of Geophysical Research: Earth Surface 119, 1455-1483.
Lauer, J. W. & Parker, G. (2008). Modeling framework for sediment deposition, storage, and evacuation in the floodplain of a meandering river: Theory, Water Resources Research 44, W04425, doi: 10.1029/2006WR005528.
Lauer, J. W., Viparelli, E. & Piegay, H. (2016). Morphodynamics and sediment tracers in 1-D (MAST-1D): 1-D sediment transport that includes exchange with an off-channel sediment reservoir, Advances in Water Resources 93, 135-149.
Parker, G., Shimizu, Y., Wilkerson, G. V., Eke, E. C., Abad, J. D., Lauer, J. W., Paola, C., Dietrich, W. E. & Voller, V. R. (2011). A new framework for modeling the migration of meandering rivers, Earth Surface Processes and Landforms 36, 70-86.
Viparelli, E., Lauer, J. W., Belmont, P. & Parker, G. (2013). A numerical model to develop long-term sediment budgets using isotopic sediment fingerprints, Computers & Geosciences 53, 114-122.
T
The model represent the streamwise and vertical dispersal of a patch of tracer stones in an equilibrium gravel bed. +
S
The model simulates infiltration, fluid flow, and sediment transport. Fluid behavior is influenced by sediment concentration. +
M
The model simulates the lateral migration of a meandering rivers, allowing the formation of oxbow lakes and scroll bars which may have a different erosional resistance with respect to the pristine floodplain. +
P
The model simulates transport and deposition from the dense endmember of a pyroclastic density currents generated either by impulsive column collapse or sustained fountaining eruptions. +
1
The model solves both Gary Parker's three and four equation models for sediment mixtures. A condition was incorporated in the model to solve the equation of conservation of turbulent kinetic energy (fourth equation) and to decide how to estimate the friction coefficients. <br><br>See also: Eke, E., Viparelli, E., and Parker, G., 2011. Field-scale numerical modeling of breaching as a mechanism for generating continuous turbidity currents. Geosphere, 7, 1063-1076. Doi: 10.1130/GES00607.1 +
U
The model uses physically-based calculations of radiative, sensible, latent and advective heat exchanges. +
H
The module generates hillslope profiles by routing flow from every point on a drainage divide into a channel. +
C
The module performs topographic analysis but the analysis is based on the assumption that the stream power incision model is a good approximation for channel incision. +
F
The numerical model solves the two-dimensional shallow water equations with different modes of sediment transport. Moreover are presently implemented the Savage-Hutter type model describing avalanches of granular materials (not tested yet) and the equations governing the motion of two layers of immiscible fluid. +
R
The original process models include the following:
* The MTN-Clim model (Running et al, 1987) uses topography and user supplied base station information to derive spatially variable climate variables such as radiation and to extrapolate input climate variables over topographically varying terrain.
* An ecophysiological model is adapted from BIOME-BGC (Running and Coughlan, 1988; Running and Hunt, 1993) to estimate carbon, water and potentially nitrogen fluxes from different canopy cover types.
* Distributed hydrologic models – The original RHESSys utilized a single approach, TOPMODEL, to model soil moisture redistribution and runoff production. We now include two approaches:
** TOPMODEL (Beven and Kirkby, 1979) is a quasi distributed model. TOPMODEL distributes hillslope soil moisture based on a distribution of a topograhically defined wetness index.
** An explicit routing model is adapted from DHSVM (Wigmosta et al., 1994) which models saturated subsurface throughflow and overland flow via explicit connectivity. An important modification from the grid-based routing in DHSVM is the ability to route w ater between arbitrarily shaped surface elements. This allows greater flexibility in defining surface patches and varying shape and density of surface tesselation. +
F
The present version of FVCOM includes a number of options and components as shown in Figure above. These include:
# choice of Cartesian or spherical coordinate system,
# a mass-conservative wet/dry point treatment for the flooding/drying process simulation,
# the General Ocean Turbulent Model (GOTM) modules (Burchard et al., 1999; Burchard, 2002) for optional vertical turbulent mixing schemes,
# a water quality module to simulate dissolved oxygen and other environmental indicators,
# 4-D nudging and Reduced/Ensemble Kalman Filters (implemented in collaboration with P. Rizzoli at MIT) for data assimilation,
# fully-nonlinear ice models (implemented by F. Dupont),
# a 3-D sediment transport module (based on the U.S.G.S. national sediment transport model) for estuarine and near-shore applications, and
# a flexible biological module (FBM) for food web dynamics study.
FBM includes seven groups: nutrients, autotrophy, heterotrophy, detritus, dissolved organic matter, bacteria, and other. With various pre-built functions and parameters for these groups, GBM allows users to either select a pre-built biological model (such as NPZ, NPZD, etc.) or to build their own biological model using the pre-defined pool of biological variables and parameterization functions. +
P
The primary objectives are: (1) simulation of hydrologic processes including evaporation, transpiration, runoff, infiltration, and interflow as determined by the energy and water budgets of the plant canopy, snowpack, and soil zone on the basis of distributed climate information (temperature, precipitation, and solar radiation); (2) simulation of hydrologic water budgets at the watershed scale for temporal scales ranging from days to centuries; (3) integration of PRMS with other models used for
natural-resource management or with models from other scientific disciplines; and (4) providing a modular design that allows for selection of alternative hydrologic-process algorithms from the standard PRMS module library. +
C
D
The rainfall-excess components include soil-moisture accounting, pervious-area rainfall excess, impervious-area rainfall excess, and parameter optimization. The Green-Ampt equation is used in the calculations of infiltration and pervious area rainfall excess. A Rosenbrock optimization procedure may be used to aid in calibrating several of the infiltration and soil-moisture accounting parameters. Kinematic wave theory is used for both overland-flow and channel routing. There are three solution techniques available: method of characteristics, implicit finite difference method, and explicit finite difference method. Two soil types may be defined. Overland flow may be defined as turbulent or laminar. Detention reservoirs may be simulated as linear storage or using a modified-Puls method. Channel segments may be defined as gutter, pipe, triangular cross section, or by explicitly specifying the kinematic channel parameters alpha and m. +
T
The two key elements of TUGS model are a surface-based bedload transport equation that allows for calculation of transport rate and grain size distribution of both gravel and sand (Wilcoco and Crowe 2003), and functions that link bedload grain size distributions with surface and subsurface grain size distributions (Hoey and Ferguson 1994; Toro-Escobar et al. 1996; Cui 2007a). +
G
This code will erode cells according to a shear stress and also deposit sediment based on the concentration of sediment in a modeled water column. Additionally it has a headcut that migrates upstream and as the headcut erodes it deposits sediment downstream that the model must erode. +
D
This component calculates the flux of soil on a hillslope according to a soil depth-dependent linear diffusion rule. +
This driver program solves the equations describing horizontal velocities in a buoyant, turbulent, plane jet issuing in a normal direction from a coast into a large volume of still fluid. Sedimentation under the jet is modelled using a hemipelagic rain formulation, bedload dumping, and downslope diffusion due to slides, slumps and turbidity currents. +
K
This model is designed to represent infiltration (Green-Ampt), rainfall interception, and runoff (kinematic wave). Hydraulic roughness is accounted for using a depth-dependent Manning-type flow resistance equation.
For details on the model equations and numerical solution, see the following references:
Rengers, F.K., McGuire, L.A., Kean, J.W., Staley, D.M. and Hobley, D.E.J., 2016.
Model simulations of flood and debris flow timing in steep catchments after wildfire.
Water Resources Research, 52(8), pp.6041-6061.
McGuire, L.A. and Youberg, A.M., 2019. Impacts of successive wildfire on soil hydraulic properties:
Implications for debris flow hazards and system resilience. Earth Surface Processes and Landforms,
44(11), pp.2236-2250. +
G
This tool is used to identify knickpoints using a drainage area threshold and a curvature threshold value +
S
This tool maps out local surface roughness based on the neighborhood distribution of surface normal vectors. As sediment transport processes in soil mantled landscapes tend to be diffusive, the emergence of bedrock drives an increase in surface roughness that is mapped out by this algorithm. +
D
This tool works under the assumption that the channels incise approximately based on the stream power law. It identifies the channel head as the upstream limit of fluvial incision based on the chi profile of the channel. +
P
Thus the model yields not only compressional wave speeds, but also shear wave speeds and compressional and shear wave attenuation coefficients. +
C
Tidal currents
Sea waves
Swell waves
Storm surges
Tidal dispersion transport
Along-wave transport
Downslope transport by currents, swell waves, breaking waves, and sea waves
Edge erosion
Marsh processes
Along-shore transport by radiation stresses +
M
Tide-averaged flow (by tidal dispersion)
Flow erosion (assuming quasi-static propagation)
Sediment deposition
Sediment transport
Soil diffusion (aka creep)
Organic sediment production
Vegetation effect on drag, settling velocity, soil creep
Sea level rise
v.20 also includes:
Wind waves (empirical function of speed, water depth, and fetch)
Edge erosion
Identification of impounded areas
Active pond deepening
Active pond expansion +
C
Time- and length-averaged sediment transport in shelf, shoreface and surf zone environments combined with morphodynamic-driven sediment flux through inlet, along ebb tide delta and with the bay or estuar. +
Q
Time-averaged sediment transport by long-range river transport based on discharge and gradient and on short range diffusive transport based on gradient and diffusion coefficients. Thresholds for slope and discharge can be set and act as a means to keep the flow from spreading over every adjacent grid cell allowing avulsion and bifurcation processes to be modeled. +
A
W
To simulate real weather and to do simulations with coarse resolutions, a minimum set of physics components is required, namely radiation, boundary layer and land-surface parameterization, convective parameterization, subgrid eddy diffusion, and microphysics. Since the model is developed for both research and operational groups, sophisticated physics schemes and simple physics schemes are needed in the model. The objectives of the WRF physics development are to implement a basic set of physics into the WRF model and to design a user friendly physics interface. Since the WRF model is targeted at resolutions of 1-10 km, some of physics schemes might not work properly in this high resolution (e.g. cumulus parameterization). However, at this early stage of model development, only existing physics schemes are implemented, and most of them are taken from current mesoscale and cloud models. In the future, new physics schemes designed for resolutions of 1-10 km should be developed and implemented. See http://www.mmm.ucar.edu/wrf/users/docs/wrf-phy.html#physics_scheme for more information +
S
D
Tool is used to regionalize a study area into zones with 'common physical characteristics' with the underlying aim of differentiating areas of influence of various physical processes. Regionalization attempts to aggregate spatial units or observations into clusters based on spatial continuity as well as attribute similarity.
Geometry metrics are derived from satellite data analysis and include a.o. island area, island aspect ratio, island fractal dimension, and surrounding channel metric, channel width, channel sinousity, number of outflow channels, convexity. +
C
Tracking of cosmogenic nuclides on surface and in fluvial system of a landslide dominated drainage basin +
G
C
L
G
Two-dimensional depth-averaged flows, particularly suitable for tsunami and storm surge modeling, and has also bee used for dam breaks and flooding of river valleys. +
N
Uses a non-local means filter image processing technique to perform filtering/smoothing of a DEM. +
Uses the Python NetCDF toolkit (see python-netcdf on apt) to pull the desired information out of NetCDF files generated from NEXRAD (WSR-88D) outputs +
C
Using energetics-based formulations for wave-driven sediment transport, we develop a robust methodology for estimating the morphodynamic evolution of a cross-shore sandy coastal profile. The wave-driven cross-shore
sediment flux depends on three components: two onshore-directed terms (wave asymmetry and wave streaming) and an offshore-directed slope term. The cross-shore sediment transport formulation defines a dynamic equilibrium profile and, by perturbing about this steady-state profile, we present an advection-diffusion formula for profile evolution. Morphodynamic Péclet analysis suggests that the shoreface is diffusionally dominated. Using this depth-dependent characteristic diffusivity timescale, we distinguish a morphodynamic depth of closure for a given time envelope. Even though wave-driven sediment transport can (and will) occur at deeper depths, the rate of morphologic bed changes in response to shoreline change becomes increasingly slow below this morphodynamic closure depth. +
D
Watershed erosion +
O
Wave generation, propagation, shoaling, diffraction, refraction, breaking. Nonlinear wave-wave and wave-current interaction. Surf and swash hydrodynamics. +
Q
We model sedimentation in a fluvio-deltaic system under base-level changes. Possible dynamics include: (1) river aggradation (i.e., a seawards migration of the alluvial-basement transition), (2) river degradation (i.e., a landwards migration of the alluvial-basement transition), (3) regression (i.e., a seawards migration of the shoreline), and (4) transgression (e.g., a landwards migration of the shoreline). +
B
Weathering and erosion of bedrock on a hillslope; vertical and horizontal displacement due to earthquakes. +
C
Wind waves are computed by wave action propagation, tidal current are computed with a quasi static approximation. Bottom shaer stress, computed from a combination ot the two, induces bottom erosion. Suspended sediment are advected / diffused by tidal current, and eventually sedimented back. A different erosional process are used where waves break on a vertical obstacle (the vertical scarp at the marsh boundary). Vegetation is computed as a function of the ground elevation respect to the mean tidal level. Vegetation change bottom erodability and the sediment trapping. +
S
Z
D
development of dune landscapes under the interaction between aeolian sand transport and vegetation growth and response +
drying/flooding, turbulence and large eddies, stratification, internal waves, density effects of salinity, temperature and sediment, free surface flow, wave-current interaction, wind forcing, precipitation and evaporation, sediment sorting, fluid mud, morphological change, biochemical reactions, algae modelling, nutrient cycling, atmosphere-water exchange, adsorption and desorption of substances, deposition and re-suspension of particles and adsorbed substances, bacterial , predation +
F
S
fluid flow (2D potential flow), clastic sediment transport and deposition, carbonate deposition and transport, evaporate deposition, sea level change and coastline movement +
T
G
global-scale forward models of landscape evolution, dual-lithology (coarse and fine) sediment routing and stratigraphic history forced with deforming plate tectonics, paleotopographies and paleoclimate reconstructions. +
I
ice stress balance, ice mass transport / free surface, ice thermal (cold- and enthalpy-based), dual continuum hydrology, SHAKTI hydrology, GlaDS hydrology, ice damage mechanics, transient (time-dependent projection), grounding line dynamics, glacial isostatic adjustment (GIA), solid earth elastic response, sea-level fingerprints, positive degree day (PDD), surface energy balance (snow densification and surface mass balance calculation with the GEMB model), basal melt parameterizations (PICO/PICOP), empirical scalar tertiary anisotropy regime (ESTAR), uncertainty quantification capabilities (Dakota) +
D
M
D
n/a +
R
C
S
B
quasi-normal flow (1D)
downstream and transverse sediment fluxes
mass conservation (Exner) +
S
sediment transport drive by turbulent/laminar flows +
A
G
W
see: Sagy Cohen, Albert J. Kettner, James P.M. Syvitski, Balazs M. Fekete, WBMsed, a distributed global-scale riverine sediment flux model: Model description and validation, Computers and Geosciences, ISSN 0098-3004, 10.1016/j.cageo.2011.08.011. +
X
short wave propagation, infragravity waves, shear waves, swash, overtopping, overwashing, breaching, longshore current, cross-shore current, suspended sediment transport, morphological changes, dune erosion +
H
snowmelt process, skin and canopy processes, soil processes, surface water and shallow groundwater processes, river routing +
S
surface plumes, hyperpycnal plumes, sediment slope failure that results in turbidity currents or debris flows, subsidence, compaction, sediment remobilization due to waves and currents, river avulsion +
T
tAo is an open-source software designed to model the interplay between lithosphere flexure and surface transport (erosion/sedimentation), particularly during the formation of orogens and foreland sedimentary basins (see details). This 2D (cross-section) numerical model calculates 1D lithospheric flexure with different rheologies, in combination with fault kinematics, other isostatic loads, and erosion/deposition. Erosion models include both constant-rate and climate-based approaches. The programs are developed in C for Linux platforms, graphic output is produced using GMT scripts, and standard PCs match the CPU and memory requirements. The software is available under a GPL license. +
M
Y
W
virtually all earth atmospheric processes +
M
water volume flux, water supply, reservoir operations +
W
F
