This function is called by the cov_nightlight module and downloads annual data on night time illumination from NASA (product ID VNP46A4) using the blackmarbler package. You must obtain and a token from NASA to use this function and set an environmental variable called NASA_bearer to contain it. It returns a SpatRaster for the selected area and year.

cov_nightlight(shape, year, bearer, async = FALSE)

Arguments

shape

sf. sf object containing the area of interest

year

numeric. Year for which to download the data. Limited to 2012-2022

bearer

character. NASA bearer token. Click here for details of how to obtain one.

async

Whether or not the function is being used asynchronously. When TRUE the returned object is a wrapped SpatRaster.

Value

a SpatRaster object when async is FALSE or a PackedSpatRaster when async is TRUE.

Author

Simon Smart simon.smart@cantab.net

Examples

if (FALSE) { # \dontrun{
x_min <- 0
x_max <- 0.5
y_min <- 52
y_max <- 52.5
poly_matrix <- matrix(c(x_min, x_min, x_max, x_max, x_min,
                        y_min, y_max, y_max, y_min, y_min), ncol = 2)
poly <- sf::st_polygon(list(poly_matrix))
shape <- sf::st_sf(1, geometry = list(poly))
sf::st_crs(shape) = 4326
raster <- cov_nightlight(shape = shape, year = 2022, bearer = Sys.getenv("NASA_bearer"))
} # }