Tool SaLEM
This is the implementation of a Soil and Landscape Evolution Model (SaLEM) for the spatiotemporal investigation of soil parent material evolution following a lithologically differentiated approach. The model needs a digital elevation model and (paleo-)climatic data for the simulation of weathering, erosion and transport processes. Weathering is controlled by user defined functions in dependence of climate conditions, local slope, regolith cover and outcropping bedrock lithology. Lithology can be supplied as a set of grids, of which each grid represents the top elevation of the underlying bedrock type.
References
- Alley, R. (2000): The Younger Dryas cold interval as viewed from central Greenland. Quaternary Science Reviews 19: 213-226.
- Bock, M., Conrad, O., Guenther, A., Gehrt, E., Baritz, R., and Boehner, J. (2018): SaLEM (v1.0) - the Soil and Landscape Evolution Model (SaLEM) for simulation of regolith depth in periglacial environments. Geosci. Model Dev., 11, 1641-1652. https://doi.org/10.5194/gmd-11-1641-2018.
- Tucker, G.E. & Slingerland, R. (1994): Erosional dynamics, flexural isostasy, and long-lived escarpments: A numerical modeling study. Journal of Geophysical Research 99: 12229-12243.
- Author: M.Bock, O.Conrad (c) 2017
- Menu: Simulation|Landscape Evolution
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Initial Surface Elevation | Grid, input | SURFACE_T0 | - | - |
| Initial Regolith Thickness (*) | Grid, input, optional | REGOLITH_T0 | Initial sediment cover (m) | - |
| Allochthone Input (*) | Grid, input, optional | ALLOCHTHONE | Allochthone input in meter per year (e.g. of aeolian origin, 'Loess'). | - |
| Output | Surface Elevation | Grid, output | SURFACE | - | - |
| Regolith Thickness | Grid, output | REGOLITH | - | - |
| Difference | Grid, output | DIFFERENCE | - | - |
| Options | Grid System | Grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Default | Floating point | REGOLITH_T0_DEFAULT | default value if no grid has been selected | Minimum: 0.000000
Default: 0.000000 |
| Default | Floating point | ALLOCHTHONE_DEFAULT | default value if no grid has been selected | Minimum: 0.000000
Default: 0.000000 |
| Climate | Parameters | CLIMATE | - | 12 Parameters:
- 1.
- 2.
- 3.
- 4. Default: 31.000000
- 5.
- 6.
- 7.
- 8.
- 9.
- 10. Available Choices:
[0] Celsius
[1] Kelvin
Default: 0
- 11. Minimum: 0.000000
Default: 0.600000
- 12. Default: 1
|
| Bedrock | Parameters | BEDROCK | - | 5 Parameters:
- 1.
- 2. 2 Fields:
- 1. [string] Frost
- 2. [string] Chemical
- 3.
- 4. Default: 0.0250 * (0.00175 * R + T - Tmax) / (-Tamp * cos(S))
- 5. Default: 0.0002 * exp(-5.0 * R)
|
| Tracers | Parameters | TRACERS | - | 8 Parameters:
- 1.
- 2.
- 3. Available Choices:
[0] no
[1] temporarily
[2] permanently
Default: 1
- 4. Minimum: 0.000000
Default: 0.000000
- 5. Minimum: 1
Default: 1
- 6. Default: 1
- 7. Minimum: 0.010000
Default: 0.500000
- 8. Default: 1
|
| Start [Years BP] | Integer | TIME_START | - | Default: 50000 |
| Stop [Years BP] | Integer | TIME_STOP | - | Default: 10000 |
| Step [Years] | Integer | TIME_STEP | - | Minimum: 1
Default: 100 |
| Diffusivity Coefficient Kd [m²/a] | Floating point | DIFFUSIVE_KD | - | Minimum: 0.000000
Default: 0.010000 |
| Neighbourhood | Choice | DIFFUSIVE_NEIGHBOURS | - | Available Choices:
[0] Neumann
[1] Moore
Default: 1 |
| (*) optional |
Command-line
Usage: saga_cmd sim_landscape_evolution 0 [-SURFACE_T0 <str>] [-REGOLITH_T0 <str>] [-REGOLITH_T0_DEFAULT <double>] [-ALLOCHTHONE <str>] [-ALLOCHTHONE_DEFAULT <double>] [-SURFACE <str>] [-REGOLITH <str>] [-DIFFERENCE <str>] [-CLIMATE_TREND <str>] [-CLIMATE_TREND_YEAR <str>] [-CLIMATE_TREND_T <str>] [-CLIMATE_TREND_T_OFFSET <double>] [-CLIMATE_ANNUAL <str>] [-CLIMATE_ANNUAL_T <str>] [-CLIMATE_ANNUAL_TMIN <str>] [-CLIMATE_ANNUAL_TMAX <str>] [-CLIMATE_ANNUAL_P <str>] [-CLIMATE_ANNUAL_T_UNIT <str>] [-CLIMATE_T_LAPSE <double>] [-CLIMATE_T_LAPSE_CELL <str>] [-BEDROCK_ROCK_LAYERS <str>] [-BEDROCK_WEATHERING <str>] [-BEDROCK_FROST <str>] [-BEDROCK_CHEMICAL <str>] [-TRACERS_POINTS <str>] [-TRACERS_LINES <str>] [-TRACERS_TRIM <str>] [-TRACERS_DIR_RAND <double>] [-TRACERS_H_DENSITY <num>] [-TRACERS_H_RANDOM <str>] [-TRACERS_V_DENSITY <double>] [-TRACERS_V_RANDOM <str>] [-TIME_START <num>] [-TIME_STOP <num>] [-TIME_STEP <num>] [-DIFFUSIVE_KD <double>] [-DIFFUSIVE_NEIGHBOURS <str>]
-SURFACE_T0:<str> Initial Surface Elevation
Grid, input
-REGOLITH_T0:<str> Initial Regolith Thickness
Grid, input, optional
-REGOLITH_T0_DEFAULT:<double> Default
Floating point
Minimum: 0.000000
Default: 0.000000
-ALLOCHTHONE:<str> Allochthone Input
Grid, input, optional
-ALLOCHTHONE_DEFAULT:<double> Default
Floating point
Minimum: 0.000000
Default: 0.000000
-SURFACE:<str> Surface Elevation
Grid, output
-REGOLITH:<str> Regolith Thickness
Grid, output
-DIFFERENCE:<str> Difference
Grid, output
-CLIMATE_TREND:<str> Long-term Temperature Signal
Table, input
-CLIMATE_TREND_YEAR:<str> Year
Table field
-CLIMATE_TREND_T:<str> Temperature
Table field
-CLIMATE_TREND_T_OFFSET:<double> Temperature Offset
Floating point
Default: 31.000000
-CLIMATE_ANNUAL:<str> Annual Climate
Table, input
-CLIMATE_ANNUAL_T:<str> Mean Temperature
Table field
-CLIMATE_ANNUAL_TMIN:<str> Minimum Temperature
Table field
-CLIMATE_ANNUAL_TMAX:<str> Maximum Temperature
Table field
-CLIMATE_ANNUAL_P:<str> Precipitation
Table field
-CLIMATE_ANNUAL_T_UNIT:<str> Temperature Unit
Choice
Available Choices:
[0] Celsius
[1] Kelvin
Default: 0
-CLIMATE_T_LAPSE:<double> Temperature Lapse Rate
Floating point
Minimum: 0.000000
Default: 0.600000
-CLIMATE_T_LAPSE_CELL:<str> Temperature Height Correction
Boolean
Default: 1
-BEDROCK_ROCK_LAYERS:<str> Lithology
Grid list, input, optional
-BEDROCK_WEATHERING:<str> Weathering Formulas
Static table
2 Fields:
- 1. [string] Frost
- 2. [string] Chemical
-BEDROCK_FROST:<str> Frost Weathering
Text
Default: 0.0250 * (0.00175 * R + T - Tmax) / (-Tamp * cos(S))
-BEDROCK_CHEMICAL:<str> Chemical Weathering
Text
Default: 0.0002 * exp(-5.0 * R)
-TRACERS_POINTS:<str> Tracer
Shapes, output, optional
-TRACERS_LINES:<str> Tracer Paths
Shapes, output, optional
-TRACERS_TRIM:<str> Trim
Choice
Available Choices:
[0] no
[1] temporarily
[2] permanently
Default: 1
-TRACERS_DIR_RAND:<double> Randomize Direction
Floating point
Minimum: 0.000000
Default: 0.000000
-TRACERS_H_DENSITY:<num> Horizontal Density
Integer
Minimum: 1
Default: 1
-TRACERS_H_RANDOM:<str> Randomize
Boolean
Default: 1
-TRACERS_V_DENSITY:<double> Vertical Density
Floating point
Minimum: 0.010000
Default: 0.500000
-TRACERS_V_RANDOM:<str> Randomize
Boolean
Default: 1
-TIME_START:<num> Start [Years BP]
Integer
Default: 50000
-TIME_STOP:<num> Stop [Years BP]
Integer
Default: 10000
-TIME_STEP:<num> Step [Years]
Integer
Minimum: 1
Default: 100
-DIFFUSIVE_KD:<double> Diffusivity Coefficient Kd [m_/a]
Floating point
Minimum: 0.000000
Default: 0.010000
-DIFFUSIVE_NEIGHBOURS:<str> Neighbourhood
Choice
Available Choices:
[0] Neumann
[1] Moore
Default: 1