Tool Name	Slope Limited Flow Accumulation
Tool ID	26
Library ID	ta_hydrology
Version	1.0
Author(s)	O.Conrad (c) 2014

Description

Flow accumulation is calculated as upslope contributing (catchment) area using the multiple flow direction approach of Freeman (1991). For this tool the approach has been modified to limit the flow portion routed through a cell depending on the local slope. If a cell is not inclined, no flow is routed through it at all. With increasing slopes the portion of flow routed through a cell becomes higher. Cells with slopes greater than a specified slope threshold route their entire accumulated flow downhill.

References

Freeman, G.T. (1991): Calculating catchment area with divergent flow based on a regular grid. Computers and Geosciences, 17:413-22.

Parameters

Name	Type	Identifier	Description	Constraints
Input
Elevation	grid, input	DEM
Weight	grid, input, optional	WEIGHT
Output
Flow Accumulation	grid, output	FLOW
Options
Slope Minimum	floating point number	SLOPE_MIN	Assume a given minimum slope for each cell.	Minimum: 0.000000 Default: 0.000000
Slope Threshold	floating point number	SLOPE_MAX	Slope threshold, given as degree, above which flow transport is unlimited.	Minimum: 0.000000 Maximum: 90.000000 Default: 5.000000
Use Flow Threshold	boolean	B_FLOW		Default: 0
Flow Threshold	value range	T_FLOW	Flow threshold, given as amount of cells, above which flow transport is unlimited. Ignored if range equals zero.