Get seamounts — get_seamounts • oceandatr

Get seamounts data in a spatial grid or polygon

Usage

get_seamounts(
  spatial_grid = NULL,
  raw = FALSE,
  buffer = NULL,
  name = "seamounts",
  antimeridian = NULL
)

Arguments

spatial_grid: sf or terra::rast() grid, e.g. created using get_grid(). Alternatively, if raw data is required, an sf polygon can be provided, e.g. created using get_boundary(), and set raw = TRUE.
raw: logical if TRUE, spatial_grid should be an sf polygon, and the raw seamounts data in that polygon(s) will be returned
buffer: numeric; the distance from the seamount peak to include in the output. Distance should be in the same units as the spatial_grid, use e.g. sf::st_crs(spatial_grid, parameters = TRUE)$units_gdal to check units. If buffering raw data, units are metres, unless sf::sf_use_s2() is set to FALSE, in which case the units are degrees.
name: name of raster or column in sf object that is returned
antimeridian: Does spatial_grid span the antimeridian? If so, this should be set to TRUE, otherwise set to FALSE. If set to NULL (default) the function will try to check if data spans the antimeridian and set this appropriately.

Value

For buffered seamounts as gridded data, a terra::rast() or sf object, depending on the spatial_grid format. If raw = TRUE and buffer = NULL an sf POINT geometry object of seamount peaks within the polygon provided. If raw = TRUE and buffer is not NULL an sf polygon geometry object of buffered seamount peaks within the polygon provided. Note: at present, it is not possible to return gridded seamount peaks: https://github.com/emlab-ucsb/oceandatr/issues/48

Details

Seamounts are classified as peaks at least 1000m higher than the surrounding seafloor Morato et al. 2008. The seamounts peak dataset is from Yeson et al. 2021. Morato et al. 2010 found that seamounts have higher biodiversity within 30 - 40 km of the peak. To enable this radius of higher biodiversity to be included in conservation planning, the buffer argument can be set, so that each seamount peak is buffered to the radius specified

Examples

# Get EEZ data first 
bermuda_eez <- get_boundary(name = "Bermuda")
#> Cache is fresh. Reading: /tmp/Rtmpj5K8Rh/eez-2205f12f/eez.shp
#> (Last Modified: 2024-09-11 02:15:56.249906)
# Get raw seamounts data
seamount_peaks <- get_seamounts(spatial_grid = bermuda_eez, raw = TRUE)
#> Spherical geometry (s2) switched off
#> although coordinates are longitude/latitude, st_intersection assumes that they
#> are planar
#> Warning: attribute variables are assumed to be spatially constant throughout all geometries
#> Spherical geometry (s2) switched on
plot(seamount_peaks["Depth"])

# Get gridded seamount data
bermuda_grid <- get_grid(boundary = bermuda_eez, crs = '+proj=laea +lon_0=-64.8108333 +lat_0=32.3571917 +datum=WGS84 +units=m +no_defs', resolution = 10000)
#buffer seamounts to a distance of 30 km (30,000 m)
seamounts_gridded <- get_seamounts(spatial_grid = bermuda_grid, buffer = 30000)
#> Spherical geometry (s2) switched off
#> although coordinates are longitude/latitude, st_intersection assumes that they
#> are planar
#> Warning: attribute variables are assumed to be spatially constant throughout all geometries
#> Spherical geometry (s2) switched on
terra::plot(seamounts_gridded)