Figure 3.7 Two simple world projections

figures

code

Code

library(sf)
library(tmap)
library(tmaptools)
library(dplyr)

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

tm_shape(world, bbox = bb(xlim = c(-180, 180),
                          ylim = c(-90, 90))) +
  tm_fill(col = "#aaeecc") +
  tm_graticules(x = seq(-180, 180, 15), y = seq(-90, 90, 15),
                labels.show = FALSE, lwd = 0.5) +
  tm_layout(inner.margins = 0, bg.color = "#ddeeff")

Code

tm_shape(world_lcea, bbox = bb(xlim = c(-180, 180),
                               ylim = c(-90, 90))) +
  tm_fill(col = "#aaeecc") +
  tm_graticules(x = seq(-180, 180, 15), y = seq(-90, 90, 15),
                labels.show = FALSE, lwd = 0.5) +
  tm_layout(inner.margins = 0, bg.color = "#ddeeff")

Code

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