Tool Upslope Area (interactive)
This tool allows you to specify target cells, for which the upslope contributing area shall be identified. The result will give for each cell the percentage of its flow that reaches the target cell(s).
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Interactive version (left mouse clicks will trigger the calculation for the selected cell).
References
- Freeman, G.T. (1991): Calculating catchment area with divergent flow based on a regular grid. Computers and Geosciences, 17:413-22.
- O'Callaghan, J.F. & Mark, D.M. (1984): The extraction of drainage networks from digital elevation data. Computer Vision, Graphics and Image Processing, 28:323-344.
- Qin, C. Z., Zhu, A. X., Pei, T., Li, B. L., Scholten, T., Behrens, T. & Zhou, C. H. (2011): An approach to computing topographic wetness index based on maximum downslope gradient. Precision Agriculture, 12(1), 32-43. ResearchGate.
- Quinn, P.F., Beven, K.J., Chevallier, P. & Planchon, O. (1991): The prediction of hillslope flow paths for distributed hydrological modelling using digital terrain models. Hydrological Processes, 5:59-79. ResearchGate.
- Seibert, J. & McGlynn, B. (2007): A new triangular multiple flow direction algorithm for computing upslope areas from gridded digital elevation models. Water Resources Research, Vol. 43, W04501,
C++ implementation in SAGA by Thomas Grabs (c) 2007, contact: thomas.grabs@natgeo.su.se, jan.seibert@natgeo.su.se. Wiley. - Tarboton, D.G. (1997): A new method for the determination of flow directions and upslope areas in grid digital elevation models. Water Resources Research, Vol.33, No.2, p.309-319. Wiley.
- Author: O.Conrad (c) 2001
- Menu: Terrain Analysis|Hydrology|Flow Accumulation
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Elevation | Grid, input | ELEVATION | - | - |
| Sink Routes (*) | Grid, input, optional | SINKROUTE | - | - |
| Output | Upslope Area | Grid, output | AREA | - | - |
| Options | Grid System | Grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Method | Choice | METHOD | - | Available Choices:
[0] Deterministic 8
[1] Deterministic Infinity
[2] Multiple Flow Direction
[3] Multiple Triangular Flow Directon
[4] Multiple Maximum Downslope Gradient Based Flow Directon
Default: 2 |
| Convergence | Floating point | CONVERGE | Convergence factor for Multiple Flow Direction Algorithm (Freeman 1991).
Applies also to the Multiple Triangular Flow Directon Algorithm. | Minimum: 0.001000
Default: 1.100000 |
| Contour Length | Boolean | MFD_CONTOUR | Include (pseudo) contour length as additional weighting factor in multiple flow direction routing, reduces flow to diagonal neighbour cells by a factor of 0.71 (s. Quinn et al. 1991 for details). | Default: 0 |
| (*) optional |
Command-line
this interactive tool can not be executed.