CIT Index
| Author(s) | V. Wichmann (c) 2021 |
| Library ID | ta_hydrology |
| Tool ID | 31 |
| Version | 1.0 |
| Menu | Terrain Analysis | Hydrology | Topographic Indices |
Description
The tool allows one to calculate a variant of the Stream Power Index, which was introduced to detect channel heads (channel initiation) based on a drainage area-slope threshold. The Channel Initiation Threshold (CIT) index is calculated as: CIT = SCA * tan(Slope)^2
References
Montgomery, D.R., Dietrich, W.E. (1989): Source areas, drainage density and channel initiation. Water Resources Research 25, p.1907-1918.
Montgomery, D.R., Foufoula-Georgiou, E. (1993): Channel network source representation using digital elevation models. Water Resources Research 29, p.3925-3934.
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Slope | grid, input | SLOPE | The slope grid [radians]. | - |
| Catchment Area | grid, input | AREA | The catchment area grid [map unitsz^2]. | - |
| Output | CIT Index | grid, output | CIT | The Channel Initiation Threshold index. | - |
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Area Conversion | choice | CONV | - | Available Choices:
[0] no conversion (areas already given as specific catchment area)
[1] 1 / cell size (pseudo specific catchment area)
Default: 0 |
Command Line
Usage: saga_cmd ta_hydrology 31 [-SLOPE ] [-AREA ] [-CIT ] [-CONV ]
-SLOPE: Slope
grid, input
-AREA: Catchment Area
grid, input
-CIT: CIT Index
grid, output
-CONV:
Area Conversion
choice
Available Choices:
[0] no conversion (areas already given as specific catchment area)
[1] 1 / cell size (pseudo specific catchment area)
Default: 0