Figure 3.7 Two simple world projections

figures

code

Code

library(sf)
library(tmap) # for its world dataset
library(ggplot2)
library(tmaptools)
library(dplyr)

Set up some theme stuff for the maps.

Code

theme_set(theme_void())
theme_update(
  plot.margin = unit(c(0, 0, 0, 0), "pt"),
  plot.background = element_rect(fill = "#ddeeff"),
  panel.background = element_rect(fill = NA),
  panel.border = element_rect(fill = NA, linewidth = 0.5),
  panel.grid = element_line(colour = "black", linewidth = 0.05),
  panel.ontop = TRUE
)

Use the supplied World dataset (in lat-lon EPSG 4326) and make projections as required.

Code

data("World") 
world <- World |>
  select(geometry)

# Equal area with standard parallel at 0
world_lcea <- world |>
  st_transform("+proj=cea")

That’s pretty much it. So here are the maps.

Code

ggplot(world) +
  geom_sf(fill = "#aaeecc", colour = NA) +
  coord_sf(label_graticule = "", expand = FALSE) +
  scale_x_continuous(breaks = -12:12 * 15) +
  scale_y_continuous(breaks = -6:6 * 15)

Code

ggplot(world_lcea) +
  geom_sf(fill = "#aaeecc", colour = NA) +
  coord_sf(label_graticule = "", expand = FALSE) +
  scale_x_continuous(breaks = -12:12 * 15) +
  scale_y_continuous(breaks = -6:6 * 15)

Code

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