Skip to contents

Read Land Surface Phenology from TERN

Source: R/read_phenology.R
read_phenology.Rd

Read Australian Land Surface Phenology Cloud Optimised GeoTIFF (COG) files from TERN. This product provides phenological metrics derived from MODIS MYD13A1 imagery at 500 m resolution. Data are available for years 2003–2018, with up to two growing seasons per year.

Usage

read_phenology(
  year = NULL,
  season = 1L,
  collection = "SGS",
  api_key = get_key(),
  max_tries = NULL,
  initial_delay = NULL
)

Arguments

year

An integer year (2003–2018).

season

Season number: 1 (default) or 2.

collection

Phenology metric abbreviation. One of "SGS" (default), "PGS", "EGS", "LGS", "SOS", "POS", "EOS", "LOS", "ROG", or "ROS".

api_key

A character string containing your TERN API key. Defaults to automatic detection via get_key().

max_tries

Maximum number of download retries before an error is raised. When NULL (default), resolved from getOption("nert.max_tries", 3L). Pass an integer to override for a single call.

initial_delay

Initial retry delay in seconds (doubles with each attempt). When NULL (default), resolved from getOption("nert.initial_delay", 1L). Pass an integer to override for a single call.

Value

A terra::rast() object of the national phenology mosaic for the requested year, season, and metric.

Phenology metrics

Ten phenological metrics are available (use as the collection argument):

"SGS"

Start of Growing Season (default).

"PGS"

Peak of Growing Season.

"EGS"

End of Growing Season.

"LGS"

Length of Growing Season.

"SOS"

Start of Season.

"POS"

Peak of Season.

"EOS"

End of Season.

"LOS"

Length of Season.

"ROG"

Rate of Greening.

"ROS"

Rate of Senescence.

This is a convenience wrapper around read_tern("PHENOLOGY", ...); see read_tern() for full details and additional datasets.

References

https://geonetwork.tern.org.au/geonetwork/srv/eng/catalog.search#/metadata/2bb0c81a-5a09-4a0e-bd86-5cd2be8def26

See also

Other COGs: read_asc(), read_canopy_height(), read_slga(), read_soil_diversity(), read_tern()

Examples

if (FALSE) { # interactive()
# Read Start of Growing Season for 2018, Season 1
r <- read_phenology(year = 2018)
autoplot(r)

# Read End of Growing Season for 2015, Season 2
r_egs <- read_phenology(year = 2015, season = 2, collection = "EGS")
autoplot(r_egs)

# Rate of Greening
r_rog <- read_phenology(year = 2010, collection = "ROG")
}