Property:Describe processes
From CSDMS
This is a property of type Text.
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). +
