eez: Compute the Exclusive Economic Zone (EEZ) for the Azores

In CAOP.RAA.2024: Official Administrative Map of the Azores (CAOP 2024)

Compute the Exclusive Economic Zone (EEZ) for the Azores

Description

This function calculates the Exclusive Economic Zone (EEZ) boundary for the Azores by buffering each island by a specified distance (default 200 nautical miles) and merging the resulting buffers to create a single EEZ polygon.

Usage

eez(crs = laea_azores_proj(), distance = 200)

Arguments

crs	Character or CRS object. The target coordinate reference system (CRS) for the EEZ output. Defaults to laea_azores_proj() (a custom Lambert Azimuthal Equal-Area projection centered on the Azores).
distance	Numeric. The buffer distance in nautical miles (NM) around each island. Defaults to 200 (200 NM, the standard EEZ definition). If another value is provided, it will be converted to meters.

Details

The EEZ is defined as the area 200 nautical miles from the nearest baseline of each island. This function:

• Buffers each island by ⁠distance × 1,852⁠ meters (default: 370,400 meters).

• Merges overlapping buffers into a single EEZ boundary.

• Transforms the final EEZ to the specified crs.

Value

An sf object representing the EEZ as a single POLYGON.

Examples

library(ggplot2)
ggplot() +
geom_sf(data = eez(), fill = NA, linewidth = 1, col = "gray") +
 geom_sf(data = districts(), mapping = aes(fill = district), col = "white") +
 guides(fill = "none")

# WGS 84 projection
ggplot() +
geom_sf(data = eez(crs = "EPSG:4326"), fill = NA, linewidth = 1, col = "gray") +
 geom_sf(data = districts(crs = "EPSG:4326"), mapping = aes(fill = district), col = "white") +
 guides(fill = "none")

CAOP.RAA.2024 documentation built on April 4, 2025, 4:23 a.m.