Read CMRSET Actual Evapotranspiration Data

Wrapper around read_tern() for TERN/CMRSET evapotranspiration data. Provides monthly estimates of actual ET (mm/month) at 30 m resolution from February 2000 onwards.

Usage

read_aet(
  date,
  collection = "ETa",
  api_key = NULL,
  max_tries = 3L,
  initial_delay = 1L
)

Arguments

date: A month to download (Date or character, e.g. "2023-06-01" or as.Date("2023-06-01")). The value is snapped to the first of the month internally. Required.
collection: One of "ETa" (actual evapotranspiration in mm/month, default) or "pixel_qa" (quality assurance flags).
api_key: A character string containing your TERN API key. Defaults to automatic detection from your .Renviron or .Rprofile. See get_key() for setup.
max_tries: An integer giving the maximum number of download retries before an error is raised. Defaults to 3.
initial_delay: An integer giving the initial retry delay in seconds (doubles with each attempt). Defaults to 1.

Value

A terra::rast() object of the requested ET collection.

References

CMRSET portal: https://portal.tern.org.au/metadata/TERN/9fefa68b-dbed-4c20-88db-a9429fb4ba97

CMRSET DOI: https://dx.doi.org/10.25901/gg27-ck96

Examples

if (FALSE) { # interactive()
# Actual evapotranspiration (ETa) for June 2023 (mm/month)
r_eta <- read_aet("2023-06-01")
autoplot(r_eta)

# January 2023 ET
r_jan <- read_aet("2023-01-01")

# Quality assurance flags for June 2023
r_qa <- read_aet("2023-06-01", collection = "pixel_qa")

# ET from February 2000 (earliest available)
r_early <- read_aet("2000-02-01")

# Current/recent ET (within last month)
r_recent <- read_aet(Sys.Date())
}