SAGA.ta_slope_stability.3: WETNESS

<br/>This tool calculates a topographic wetness index (TWI) following Montgomery & Dietrich (1994) that can be used to estimate the degree of saturation of unconsolidated, permeable materials above (more or less) impermeable bedrock. In contrast to the common TOPMODEL (Beven & Kirkby, 1979) - based TWI, this index differs in such that it considers hydraulic conductivity to be constant in a soil mantle overlying relatively impermeable bedrock. Also, it uses the sine of the slope rather than its tangens, which is more correct and significantly matters for steeper slopes that give raise to landslides. For computation, a slope (in radians) and a catchment area (in m2) grid are required. Additionally, information on groundwater recharge (m/hr), material hydraulic conductivity (m/hr), and depth to potential shear plane (m) are required that can be specified either globally or through grids. The tool produces a continuous wetness index (-) where cells with WI values > 1 (overland flow) set to 1, and optionally creates a classified WI grid rendering three saturation classes:.<br/>0): Low moisture (WI smaller 0.1)<br/>1): Partially wet (0.1 smaller WI smaller 1)<br/>2): Saturation zone (WI larger 1)<br/><br/>References:<br/><a href="http://www.tandfonline.com/doi/abs/10.1080/02626667909491834">Beven, K.J., Kirkby, M.J. (1979) A physically-based variable contributing area model of basin hydrology. Hydrology Science Bulletin, 24, 43-69.</a>.<br/><br/><a href="http://www.agu.org/pubs/crossref/1994/93WR02979.shtml">Montgomery D. R., Dietrich, W. E. (1994) A physically based model for the topographic control on shallow landsliding. Water Resources Research, 30, 1153-1171.</a>.<br/>

Inputs

A DEM

format
href
Please set a value for DEM.

A grid representing minimum material hydraulic conductivity (in m/hr)

format
href
Please set a value for Cmin.

A grid representing maximum material hydraulic conductivity (in m/hr)

format
href
Please set a value for Cmax.

A grid representing minimum groundwater recharge (in m/hr)

format
href
Please set a value for Dmin.

A grid representing maximum groundwater recharge (in m/hr)

format
href
Please set a value for Dmax.

A grid representing minimum depth to potential shear plane (in m)

format
href
Please set a value for Emin.

A grid representing maximum depth to potential shear plane (in m)

format
href
Please set a value for Emax.

Constant value if no raster set

number

Constant value if no raster set

number

Constant value if no raster set

number

Constant value if no raster set

number

Constant value if no raster set

number

Constant value if no raster set

number

Number of sampling cycles

integer

Catchment Area Calculation

string

Preprocessing

boolean

Outputs

Resulting wetness index (-) grid

format
transmission

Classified wetness (-) grid

format
transmission

Execution options

successUri
inProgressUri
failedUri

format

mode

Execute End Point

View the execution endpoint of a process.

View the alternative version in HTML.

{"id": "SAGA.ta_slope_stability.3", "title": "WETNESS", "description": "<br/>This tool calculates a topographic wetness index (TWI) following Montgomery & Dietrich (1994) that can be used to estimate the degree of saturation of unconsolidated, permeable materials above (more or less) impermeable bedrock. In contrast to the common TOPMODEL (Beven & Kirkby, 1979) - based TWI, this index differs in such that it considers hydraulic conductivity to be constant in a soil mantle overlying relatively impermeable bedrock. Also, it uses the sine of the slope rather than its tangens, which is more correct and significantly matters for steeper slopes that give raise to landslides. For computation, a slope (in radians) and a catchment area (in m2) grid are required. Additionally, information on groundwater recharge (m/hr), material hydraulic conductivity (m/hr), and depth to potential shear plane (m) are required that can be specified either globally or through grids. The tool produces a continuous wetness index (-) where cells with WI values > 1 (overland flow) set to 1, and optionally creates a classified WI grid rendering three saturation classes:.<br/>0): Low moisture (WI smaller 0.1)<br/>1): Partially wet (0.1 smaller WI smaller 1)<br/>2): Saturation zone (WI larger 1)<br/><br/>References:<br/><a href=\"http://www.tandfonline.com/doi/abs/10.1080/02626667909491834\">Beven, K.J., Kirkby, M.J. (1979) A physically-based variable contributing area model of basin hydrology. Hydrology Science Bulletin, 24, 43-69.</a>.<br/><br/><a href=\"http://www.agu.org/pubs/crossref/1994/93WR02979.shtml\">Montgomery D. R., Dietrich, W. E. (1994) A physically based model for the topographic control on shallow landsliding. Water Resources Research, 30, 1153-1171.</a>.<br/>", "version": "1.0.0", "jobControlOptions": ["sync-execute", "async-execute", "dismiss"], "outputTransmission": ["value", "reference"], "links": [{"rel": "http://www.opengis.net/def/rel/ogc/1.0/execute", "type": "application/json", "title": "Execute End Point", "href": "http://demo.mapmint.com/ogc-api/processes/SAGA.ta_slope_stability.3/execution"}, {"rel": "alternate", "type": "text/html", "title": "Execute End Point", "href": "http://demo.mapmint.com/ogc-api/processes/SAGA.ta_slope_stability.3/execution.html"}], "inputs": {"DEM": {"title": "DEM", "description": "A DEM", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", 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["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}], "nullable": true}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "Cmin"}, "Cmax": {"title": "Max hydraulic conductivity grid (m/hr) ", "description": "A grid representing maximum material hydraulic conductivity (in m/hr)", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}], "nullable": true}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "Cmax"}, "Dmin": {"title": "Min groundwater recharge grid (m/hr) ", "description": "A grid representing minimum groundwater recharge (in m/hr)", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}], "nullable": true}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "Dmin"}, "Dmax": {"title": "Max groundwater recharge grid (m/hr) ", "description": "A grid representing maximum groundwater recharge (in m/hr)", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}], "nullable": true}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "Dmax"}, "Emin": {"title": "Min material depth grid (m)", "description": "A grid representing minimum depth to potential shear plane (in m)", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}], "nullable": true}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "Emin"}, "Emax": {"title": "Max material depth grid (m)", "description": "A grid representing maximum depth to potential shear plane (in m)", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}], "nullable": true}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "Emax"}, "fCmin": {"title": "Min global material conductivity (m/hr)", "description": "Constant value if no raster set", "schema": {"type": "number", "default": 2.7, "format": "double", "nullable": true}, "id": "fCmin"}, "fCmax": {"title": "Max global material conductivity (m/hr)", "description": "Constant value if no raster set", "schema": {"type": "number", "default": 2.7, "format": "double", "nullable": true}, "id": "fCmax"}, "fDmin": {"title": "Min global groundwater recharge (m/hr)", "description": "Constant value if no raster set", "schema": {"type": "number", "default": 0.001, "format": "double", "nullable": true}, "id": "fDmin"}, "fDmax": {"title": "Max global groundwater recharge (m/hr)", "description": "Constant value if no raster set", "schema": {"type": "number", "default": 0.001, "format": "double", "nullable": true}, "id": "fDmax"}, "fEmin": {"title": "Min global material depth (m)", "description": "Constant value if no raster set", "schema": {"type": "number", "default": 1, "format": "double", "nullable": true}, "id": "fEmin"}, "fEmax": {"title": "Max global material depth (m)", "description": "Constant value if no raster set", "schema": {"type": "number", "default": 1, "format": "double", "nullable": true}, "id": "fEmax"}, "fH": {"title": "Parameter sampling runs", "description": "Number of sampling cycles", "schema": {"type": "integer", "default": 1, "nullable": true}, "id": "fH"}, "METHOD": {"title": "Catchment Area Calculation", "description": "Catchment Area Calculation", "schema": {"type": "string", "default": "Multiple Flow Direction", "enum": ["Deterministic 8", "Rho 8", "Braunschweiger Reliefmodell", "Deterministic Infinity", "Multiple Flow Direction", "Multiple Triangular Flow Directon"], "nullable": true}, "id": "METHOD"}, "PREPROC": {"title": "Preprocessing", "description": "Preprocessing", "schema": {"type": "boolean", "default": false, "enum": ["true", "false"], "nullable": true}, "id": "PREPROC"}}, "outputs": {"F": {"title": "WI values", "description": "Resulting wetness index (-) grid", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}]}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "F"}, "G": {"title": "WI classes", "description": "Classified wetness (-) grid", "extended-schema": {"oneOf": [{"allOf": [{"$ref": "http://zoo-project.org/dl/link.json"}, {"type": "object", "properties": {"type": {"enum": ["image/tiff", "application/x-ogc-envi", "application/x-ogc-aaigrid", "image/png"]}}}]}, {"type": "object", "required": ["value"], "properties": {"value": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}}}]}, "schema": {"oneOf": [{"type": "string", "contentEncoding": "base64", "contentMediaType": "image/tiff"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-envi"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "application/x-ogc-aaigrid"}, {"type": "string", "contentEncoding": "base64", "contentMediaType": "image/png"}]}, "id": "G"}}}

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Last modified: Sat Feb 19 15:43:34 CET 2022