getVariables: Get variables

In ecotrends: Temporal Trends in Ecological Niche Models

Get variables

Description

This function downloads a specified time series of variables from a specified environmental data source, optionally (to save download time) within a specified region. Currently "TerraClimate" (Abatzoglou et al., 2018) is the only implemented data source.

Usage

getVariables(
  source = "TerraClimate",
  vars = varsAvailable(source)$vars,
  years = varsAvailable(source)$years,
  region = c(-180, 180, -90, 90),
  file = NULL,
  verbosity = 2
)

Arguments

source	source to import the raster variables from, e.g. "TerraClimate" (currently the only one implemented)
vars	character vector of the names of the variables to be imported. Run varsAvailable() for options. The default is to download all available variables from the specified 'source'. Note that the download can take a long time, especially for many variables, long series of years, and/or large regions.
years	year range to get the variables from (e.g. 1979:2013). Note that the download can take a long time for long series of years.
region	optional length-four numeric vector (xmin, xmax, ymin, ymax geodetic coordinates in degrees), SpatExtent or SpatVector polygon delimiting the region of the world for which the variables should be downloaded. See e.g. fuzzySim::getRegion() for suggestions. The larger the region, the longer the download time.
file	optional file name (including the path, not including the filename extension) if you want the downloaded variable rasters to be saved on disk, in which case they are saved as a compressed multi-layer GeoTIFF. If 'file' already exists in the working directory, variables are imported from there.
verbosity	integer value indicating the amount of messages to display. The default is 2, for the maximum number of messages available.

Value

multi-layer SpatRaster

Author(s)

A. Marcia Barbosa

References

Abatzoglou, J.T., S.Z. Dobrowski, S.A. Parks, K.C. Hegewisch (2018) Terraclimate, a high-resolution global dataset of monthly climate and climatic water balance from 1958-2015. Scientific Data, 5, Article number: 170191. doi: 10.1038/sdata.2017.191(2018). Database URL: https://www.climatologylab.org/terraclimate.html

See Also

varsAvailable()

Examples

if (interactive()) {

# note these downloads may take long!

vars <- ecotrends::getVariables(vars = c("tmin", "tmax", "ppt", "pet", "ws"),
years = 1981:1990, region = terra::ext(-11, -4, 37, 45), file = paste0(tempdir(), "/variables"))

# tempdir() is here to comply with CRAN policy, but you should normally
# use a directory that you can access again when reopening R
# to avoid downloading the variables again every time

names(vars)

terra::plot(vars[[1:6]])

}

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