spatialEco (version 2.0-3)

dahi: Diurnal Anisotropic Heat Index

Description

Simple approximation of the anisotropic diurnal heat (Ha) distribution

Usage

dahi(x, amax = 202.5)

Value

terra SpatRaster class object Diurnal Anisotropic Heat Index

Arguments

x

An elevation raster of class terra SpatRaster

amax

The Alpha Max (amax) parameter in degrees defined as: minimum = 0, maximum = 360 with the default = 202.500

Author

Jeffrey S. Evans <[email protected]>

Details

The Diurnal Anisotropic Heat Index is based on this equation. Ha = cos(amax - a) * arctan(b) Where; amax defines the aspect with the maximum total heat surplus, a is the aspect and b is the slope angle. Please note that all parameters are converted to radians.

References

Boehner, J., and Antonic, O. (2009) Land-surface parameters specific to topo-climatology. In: Hengl, T., & Reuter, H. (Eds.), Geomorphometry - Concepts, Software, Applications. Developments in Soil Science, 33:195-226

Examples

library(terra)
elev <- rast(system.file("extdata/elev.tif", package="spatialEco"))
Ha <- dahi(elev)
  plot(Ha, col=grey(0:100/100), smooth=TRUE)