Tool Name	Upslope and Downslope Curvature
Tool ID	26
Library ID	ta_morphometry
Version	1.0
Author(s)	P.Gandelli, O.Conrad (c) 2015

Description

This tool first calculates the local curvature of a cell as sum of the gradients (i.e. tangens of slope) to its neighbour cells. This is a simple estimation of the general curvature and is strongly correlated with general curvatures calculated with other methods (e.g. Zevenbergen & Thorne 1987). Then upslope curvature is calculated as the distance and flow proportional weighted average local curvature over a cell's upslope contributing area following the multiple flow direction algorithm after Freeman (1991). In a similar way the downslope curvature is calculated by summarizing the curvatures of all hydrologically downslope connected cells. The local upslope/downslope curvatures just take the immediately neighboured cells into account.

Parameters

Name	Type	Identifier	Constraints
Input
Elevation	grid, input	DEM
Output
Local Curvature	grid, output	C_LOCAL
Upslope Curvature	grid, output	C_UP
Local Upslope Curvature	grid, output	C_UP_LOCAL
Downslope Curvature	grid, output	C_DOWN
Local Downslope Curvature	grid, output	C_DOWN_LOCAL
Options
Upslope Weighting	floating point number	WEIGHTING	Minimum: 0.000000 Maximum: 1.000000 Default: 0.500000