pixelArea: Average pixel area

In ecotrends: Temporal Trends in Ecological Niche Models

Average pixel area

Description

This function uses the terra::cellSize() function to compute (and optionally map) the area covered by each (optionally non-NA) pixel in a raster map; and then it computes either the mean or the centroid pixel area in that map, for an idea of pixel size in that region. Pixel size can vary widely across latitudes, especially in unprojected longitude-latitude rasters, but also in rasters projected to other non-equal-area coordinate reference systems.

Usage

pixelArea(
  rast,
  type = "mean",
  unit = "m",
  mask = TRUE,
  map = TRUE,
  verbosity = 2
)

Arguments

rast	SpatRaster for which to compute the pixel area
type	character value indicating whether the output value should be the "mean" (default) or "centroid" pixel area
unit	numeric value indicating the units for the output value: either "m" (default) or "km" squared.
mask	logical value (default TRUE) indicating whether to consider only the areas of non-NA pixels
map	logical value (default TRUE) indicating whether to also plot a map
verbosity	integer value indicating the amount of messages to display. The default is 2, for the maximum number of messages available.

Value

numeric value

Author(s)

A. Marcia Barbosa, wrapping 'terra' functions by Robert H. Hijmans

See Also

terra::cellSize(), which this function wraps

Examples

r <- terra::rast(system.file("ex/elev.tif", package = "terra"))

pixelArea(r)

pixelArea(r, unit = "km")

ecotrends documentation built on Aug. 8, 2025, 6:11 p.m.