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Read data from Google Earth Engine

Source: R/read_gee.R
read_gee.Rd

Central dispatcher for all GEE dataset reads. Accepts a dataset identifier (name or alias) and delegates to the appropriate internal handler. For most use cases, prefer the convenience functions (e.g., read_modis_ndvi(), read_era5()) which provide named parameters and dataset-specific documentation.

Usage

read_gee(
  dataset_id,
  ...,
  backend = c("rest", "rgee"),
  cache = TRUE,
  max_tries = 3L,
  initial_delay = 1
)

Arguments

dataset_id

Character. Dataset name or alias. Use gee_datasets() to list all available datasets.

...

Arguments passed to the dataset-specific handler. Common arguments include date, region, collection, depth. See the convenience function documentation for dataset-specific parameters.

backend

Character. "rest" (default) or "rgee". The REST backend requires no Python; the rgee backend supports advanced server-side computations.

cache

Logical. Use disk cache for repeated queries? Default TRUE.

max_tries

Integer. Maximum retry attempts for network failures. Default 3L.

initial_delay

Numeric. Initial delay in seconds before retry (doubles each attempt). Default 1.

Value

A terra::rast() SpatRaster object.

Supported datasets

Use gee_datasets() to list all available datasets with metadata.

Tier 1 — Specialised handlers (QA masking):

  • modis_ndvi — MODIS Terra NDVI 16-day 1km

  • modis_lst — MODIS Terra LST 8-day 1km

  • era5_temp — ERA5-Land daily 2m temperature

  • era5_precip — ERA5-Land daily precipitation

  • chirps_precip — CHIRPS daily precipitation

  • srtm_elevation — NASA SRTM 30m elevation (static)

Tier 2 — Specialised handlers (soil, computed indices):

  • slga_cly, slga_snd, slga_slt, slga_awc, slga_bdw, slga_phc, slga_nto — SLGA soil properties (Australia, static)

  • sentinel2_ndvi — Sentinel-2 NDVI 10m (computed, cloud-masked)

  • landsat_ndvi — Landsat 9 NDVI 30m (computed, cloud-masked)

Tier 3 — Generic handler (global datasets):

  • worldclim_bio — WorldClim V2 bioclimatic variables ~1km (static)

  • openlandmap_soc — OpenLandMap soil organic carbon 250m (static)

  • openlandmap_clay — OpenLandMap clay content 250m (static)

  • openlandmap_ph — OpenLandMap soil pH 250m (static)

User-registered: Any dataset added via gee_register_dataset() is automatically dispatchable through the generic handler.

See also

collect_gee_data() for batch point extraction returning a data.table::data.table.

Other GEE readers: read_chirps(), read_era5(), read_landsat(), read_modis_lst(), read_modis_ndvi(), read_sentinel2(), read_slga(), read_srtm(), read_worldclim()

Examples

if (FALSE) { # interactive()
# Using the dispatcher directly
ndvi <- read_gee("MODIS_NDVI", date = "2024-06-15",
                 region = terra::ext(138, 140, -36, -34))

# Aliases are case-insensitive
elev <- read_gee("srtm", region = terra::ext(138, 140, -36, -34))

# Equivalent convenience function (preferred)
ndvi <- read_modis_ndvi(date = "2024-06-15",
                        region = terra::ext(138, 140, -36, -34))
}