World map of a marine spatial metric — ggmap

Plots a marine spatially-explicit metric on a World map. Basemap layers (continents, oceans, graticules) come from the Natural Earth website https://www.naturalearthdata.com/. The map is plotted in the Robinson projection (EPSG = 54030).

Usage

ggmap_marine(data, metric, title = NULL, palette = viridisLite::turbo(n = 100))

Arguments

data: an sf object. The spatial layer (POLYGONS, POINTS, etc.) containing the variable metric for which values are to be mapped. For aesthetic purposes, this layer should contain only marine values (terrestrial areas will be masked by the continent layer). See ggmap_terrestrial() for mapping a freshwater (or terrestrial) layer. This spatial layer must be defined in the WGS84 coordinate system (EPSG=4326).
metric: a character of length 1. The column in data for which values are to be mapped. This variable must be numeric.
title: a character of length 1. The title of the map (legend title). Default is NULL (no title).
palette: a character of colors used to categorize the values of metric. Default is viridisLite::turbo() with 100 colors.

Value

A ggplot object.

Examples

## Attach packages ----
library("rphenofish")
library("ggplot2")

## Path to example marine layer ----
file_name <- system.file(file.path("extdata", "marine_fish_richness.gpkg"), 
                         package = "rphenofish")

## Import example marine layer ----
marine_fish_richness <- sf::st_read(file_name, quiet = TRUE)

marine_fish_richness
#> Simple feature collection with 232 features and 3 fields
#> Geometry type: MULTIPOLYGON
#> Dimension:     XY
#> Bounding box:  xmin: -180 ymin: -89.9 xmax: 180 ymax: 86.9194
#> Geodetic CRS:  WGS 84
#> First 10 features:
#>    ECO_CODE                                      ECOREGION richness
#> 1     20001                                North Greenland        8
#> 2     20002                         North and East Iceland       12
#> 3     20003                           East Greenland Shelf       12
#> 4     20004                           West Greenland Shelf       53
#> 5     20005       Northern Grand Banks - Southern Labrador      118
#> 6     20006                              Northern Labrador      153
#> 7     20008                                 Hudson Complex      150
#> 8     20011 Beaufort-Amundsen-Viscount Melville-Queen Maud       70
#> 9     20012     Beaufort Sea - continental coast and shelf       91
#> 10    20013                                    Chukchi Sea       96
#>                              geom
#> 1  MULTIPOLYGON (((-32.6413 86...
#> 2  MULTIPOLYGON (((-8.65768 67...
#> 3  MULTIPOLYGON (((-12.04675 7...
#> 4  MULTIPOLYGON (((-48.27762 7...
#> 5  MULTIPOLYGON (((-52.19067 5...
#> 6  MULTIPOLYGON (((-68.0207 67...
#> 7  MULTIPOLYGON (((-69.57845 6...
#> 8  MULTIPOLYGON (((-124.2147 7...
#> 9  MULTIPOLYGON (((-153.7874 7...
#> 10 MULTIPOLYGON (((178.316 67....

## Map marine fish richness ----
marine_map <- ggmap_marine(data   = marine_fish_richness, 
                           metric = "richness",
                           title  = "Number of marine fish species")

marine_map


if (FALSE) {
## Save map in PNG ----
ggsave(plot     = marine_map, 
       filename = "marine_fish_richness.png",
       width    = 20, 
       height   = 13, 
       units    = "cm", 
       dpi      = 300, 
       bg       = "white")
}