The eBird trends data are stored in a tabular format, where each row gives
the trend estimate for a single cell in a 27 km x 27 km equal area grid. For
many applications, an explicitly spatial format is more useful. This function
uses the cell center coordinates to convert the tabular trend estimates to
raster format in terra
SpatRaster format.
Usage
rasterize_trends(
trends,
layers = c("abd_ppy", "abd_ppy_lower", "abd_ppy_upper"),
trim = TRUE
)
Arguments
- trends
data frame; trends data for a single species as returned by
load_trends()
.- layers
character; column names in the trends data frame to rasterize. These columns will become layers in the raster that is created.
- trim
logical; flag indicating if the returned raster should be trimmed to remove outer rows and columns that are NA. If
trim = FALSE
the returned raster will have a global extent, which can be useful if rasters will be combined across species with different ranges.
Value
A SpatRaster object.
Examples
if (FALSE) {
# download example trends data if it hasn't already been downloaded
ebirdst_download_trends("yebsap-example")
# load trends
trends <- load_trends("yebsap-example")
# rasterize percent per year trend
rasterize_trends(trends, "abd_ppy")
}