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 number | REGOLITH_T0_DEFAULT | default value if no grid has been selected | Minimum: 0.000000 Default: 0.000000 | 
 | Default | floating point number | 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 number | TIME_START | - | Default: 50000 | 
 | Stop [Years BP] | integer number | TIME_STOP | - | Default: 10000 | 
 | Step [Years] | integer number | TIME_STEP | - | Minimum: 1 Default: 100 | 
 | Diffusivity Coefficient Kd [m²/a] | floating point number | 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 number
	Minimum: 0.000000
	Default: 0.000000
  -ALLOCHTHONE:<str>              	Allochthone Input
	grid, input, optional
  -ALLOCHTHONE_DEFAULT:<double>   	Default
	floating point number
	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 number
	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 number
	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 number
	Minimum: 0.000000
	Default: 0.000000
  -TRACERS_H_DENSITY:<num>        	Horizontal Density
	integer number
	Minimum: 1
	Default: 1
  -TRACERS_H_RANDOM:<str>         	Randomize
	boolean
	Default: 1
  -TRACERS_V_DENSITY:<double>     	Vertical Density
	floating point number
	Minimum: 0.010000
	Default: 0.500000
  -TRACERS_V_RANDOM:<str>         	Randomize
	boolean
	Default: 1
  -TIME_START:<num>               	Start [Years BP]
	integer number
	Default: 50000
  -TIME_STOP:<num>                	Stop [Years BP]
	integer number
	Default: 10000
  -TIME_STEP:<num>                	Step [Years]
	integer number
	Minimum: 1
	Default: 100
  -DIFFUSIVE_KD:<double>          	Diffusivity Coefficient Kd [m_/a]
	floating point number
	Minimum: 0.000000
	Default: 0.010000
  -DIFFUSIVE_NEIGHBOURS:<str>     	Neighbourhood
	choice
	Available Choices:
	[0] Neumann
	[1] Moore
	Default: 1