Tool Name	Valley Depth
Tool ID	7
Library ID	ta_channels
Version	1.0
Author(s)	O.Conrad (c) 2012

Description

Valley depth is calculated as difference between the elevation and an interpolated ridge level. Ridge level interpolation uses the algorithm implemented in the 'Vertical Distance to Channel Network' tool. It performs the following steps:
- Definition of ridge cells (using Strahler order on the inverted DEM).
- Interpolation of the ridge level.
- Subtraction of the original elevations from the ridge level.

Parameters

Name	Type	Identifier	Description	Constraints
Input
Elevation	grid, input	ELEVATION
Output
Valley Depth	grid, output	VALLEY_DEPTH
Ridge Level	grid, output, optional	RIDGE_LEVEL
Options
Tension Threshold	floating point number	THRESHOLD	Maximum change in elevation units (e.g. meter), iteration is stopped once maximum change reaches this threshold.	Minimum: 0.000000 Default: 1.000000
Maximum Iterations	integer number	MAXITER	Maximum number of iterations, ignored if set to zero	Minimum: 0 Default: 0
Keep Ridge Level above Surface	boolean	NOUNDERGROUND		Default: 1
Ridge Detection Threshold	integer number	ORDER		Minimum: 1 Maximum: 7 Default: 4