MigConnectivity (version 0.4.7)

getIsoMap: Get Isoscape map getIsoMap

Description

The getIsoMap function downloads predicted isoscape maps from https://wateriso.utah.edu/waterisotopes/. The function first checks whether the isoscapes are located within the directory mapDirectory. If a local copy of the isoscape is found, it's read into the environment. If not, the isoscape is downloaded and imported as a raster.

Usage

getIsoMap(
  element = "Hydrogen",
  surface = FALSE,
  period = "Annual",
  mapDirectory = NULL
)

Value

returns a global RasterLayer (resolution = 0.333'x0.3333') object for the element and period of interest

Arguments

element

The elemental isotope of interest. Currently the only elements that are implemented are 'Hydrogen' (default) and 'Oxygen'

surface

DEPRECATED function no longer returns surface water values. Default is 'FALSE' which returns the precipitation isotopes ratio.

period

The time period of interest. If 'Annual' (default) returns a raster of mean annual values in precipitation for the element. If 'GrowingSeason' returns growing season values in precipitation for element of interest.

mapDirectory

Directory to save/read isotope map from. Can use relative or absolute addressing. The default value (NULL) downloads to a temporary directory, so we strongly recommend changing this from the default unless you're sure you're not going to need these data more than once.

Examples

# \donttest{
  map <- getIsoMap(element = "Hydrogen", period = "GrowingSeason")
# }