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upslope.area: Upslope contributing area and wetness index calculation

Description Usage Arguments Note Author(s) References Examples

Description

Determine upslope contributing area based on an elevation raster and, optionally, compute the topographic wetness index.

Usage

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upslope.area(dem, log = TRUE, atb = FALSE, deg = 0.1, fill.sinks = TRUE)

Arguments

dem

Elevation raster (in m), using a projected coordinate system with identical x and y resolutions.

log

Return the natural log of the values.

atb

If TRUE, include both the upslope contributing area and the topographic wetness index ln(a/tan(beta)). Otherwise calculate just the upslope area.

deg

Minimum intercell slope to identify with a sink (degrees).

fill.sinks

Fill sinks before calculation using the threshold angle given by deg.

Note

This is a wrapper to the function implemented in the TOPMODEL package by Wouter Buytaert.

Author(s)

Peter Metcalfe and Wouter Buytaert

References

Quinn, P. F., Beven, K. J., & Lamb, R. (1995). The In (a/tan/beta) index: How to calculate it and how to use it within the Topmodel framework. Hydrological processes, 9(2), 161-182.

Examples

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## Not run: 
require(dynatopmodel)
data(brompton)

a.atb <- upslope.area(brompton$dem, atb=TRUE)
sp::plot(a.atb, main=c("Upslope area (log(m^2/m))", "TWI log(m^2/m)"))

## End(Not run)


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