get_rap {rapr}R Documentation

Get 'Rangeland Analysis Platform' (RAP) Grids

Description

Two sets of 'Rangeland Analysis Platform' (RAP) products are available (see source argument). "rap-30m" is Landsat-derived and has approximately 30 meter resolution in WGS84 decimal degrees ("EPSG:4326"). This is the data source that has been used in the 'rapr' package since 2022. A newer source (2025), "rap-10m", is Sentinel 2-derived and has 10 meter resolution in the local WGS84 UTM zone ("EPSG:326XX", where XX is the two digit UTM zone number). See Details for the products and bands available for the different resolutions and sources.

Usage

get_rap(
  x,
  years,
  product,
  filename = NULL,
  ...,
  source = "rap-30m",
  version = "v3",
  vrt = FALSE,
  sds = FALSE,
  legacy = FALSE,
  verbose = TRUE
)

Arguments

x

Target extent. Derived from an sf, terra, raster or sp object or numeric vector containing xmin, ymax, xmax, ymin in WGS84 decimal degrees (longitude/latitude, "EPSG:4326").

years

integer. Year(s) to query. Products are available from 1986 (source="rap-30m") or 2018 (source="rap-10m") up to the year prior to the current year, based on availability of the Landsat and Sentinel 2 source data.

product

Target data: "vegetation-biomass", "vegetation-cover", and/or "vegetation-npp" for source="rap-30m"; "pft" (plant functional type cover), "gap" (canopy gap), "arte" (Artemisia spp. cover), "iag" (invasive annual grass cover), or "pj" (pinyon juniper cover) for source="rap-10m".

filename

Output filename (optional; default stores in temporary file or in memory, see terra::tmpFiles())

...

Additional arguments passed to internal query function and terra::writeRaster() (or terra::vrt() when vrt=TRUE)

source

Grid sources. Options include "rap-30m" (default; Landsat) and "rap-10m" (Sentinel 2).

version

Target version: "v3" and/or "v2" (for "rap-30m"). Currently ignored for source="rap-10m".

vrt

logical. Short circuit to return Virtual Raster Dataset (VRT) for selected grids via terra::vrt(). Default: FALSE. Note: gdalbuildvrt does not support heterogeneous projection systems, so this option is not compatible with source="rap-10m" over multiple UTM zone areas of interest.

sds

logical. Return data as a SpatRasterDataset? Helpful for results containing multiple years and products. Default FALSE returns a SpatRaster object.

legacy

logical. Use legacy (gdal_translate) method? Default: TRUE (applies only to source="rap-30m").

verbose

logical. Print messages indicating progress? Default: TRUE. For legacy=TRUE progress is shown using utils::txtProgressBar().

Details

Sources, Products, and Band Information

For "rap-30m" you can query several Landsat derived annual biomass, cover, and Net Primary Productivity products from 1986 to present:

For "rap-10m" you can query several Sentinel 2 derived cover products at 10 meter resolution from 2018 to present:

Temporary Files

Large requests may generate intermediate objects that will be stored as temporary files. See terra::tmpFiles() to view the file paths. These files will be removed when an R session ends.

Alternate Specification of Area of Interest

In lieu of a spatial object from {terra}, {raster}, {sf} or {sp} packages you may specify a bounding box using a numeric vector containing the top-left and bottom-right coordinates (xmin, ymax, xmax, ymin) in WGS84 longitude/latitude decimal degrees. This corresponds to the conventional order used in the gdal_translate -projwin option. e.g. get_rap(x = c(-120, 37, -119.99, 36.99), ...).

(1: xmin, 2: ymax)--------------------------|
        |                                   |
        |         TARGET EXTENT             |
        |  x = c(xmin, ymax, xmax, ymin)    |
        |                                   |
        |---------------------------(3: xmax, 4: ymin)

Native Resolution and Projection Systems

Native cell resolution of "rap-30m" is approximately 30m x 30m in WGS84 geographic coordinate system (longitude, latitude). Native cell resolution of "rap-10m" is 10m x 10m in the local (projected) WGS84 Universal Transverse Mercator (UTM) system.

For "rap-10m" requests spanning multiple UTM zones, either pass a SpatRaster object as x or specify template argument. In lieu of a user-specified grid system for multi-zone requests, a default CONUS Albers Equal Area projection ("EPSG:5070") with 10 m resolution will be used. See rap_projection() for options and details.

Value

a SpatRaster containing the requested product layers by year. If sds=TRUE a SpatRasterDataset where each SpatRaster contains only one product (possibly with multiple years)

References

See citation("rapr") for all references related to Rangeland Analysis Platform products.

See Also

rap_projection()


[Package rapr version 1.0.0 Index]