Tool CIT Index
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.
- Author: V. Wichmann (c) 2021
- Menu: Terrain Analysis|Hydrology|Topographic Indices
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 <str>] [-AREA <str>] [-CIT <str>] [-CONV <str>]
-SLOPE:<str> Slope
Grid, input
-AREA:<str> Catchment Area
Grid, input
-CIT:<str> CIT Index
Grid, output
-CONV:<str> 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