Figure 3.9 Equal area world in a square

figures

code

This equal-area projection could replace Web Mercator as the top level global web tile ‘world in a square’.

With astonishing foresight, it was proposed for that purpose in this paper in 1986:

Tobler WR and ZT Chen. 1986. A quadtree for global information storage. Geographical Analysis 18(4) 360–371. doi: 10.1111/j.1538-4632.1986.tb00108.x.

Given the upset that accompanied the Gall-Peters projection, another ‘odd-looking’ equal-area projection (only ‘odd’ because people are so accustomed to Mercator), it’s not clear it would catch on! See this paper for a discussion of that controversy:

Crampton, J. 1994. Cartography’s defining moment: the Peters projection controversy, 1974–1990. Cartographica 31(4) 16–32. doi: 10.3138/1821-6811-L372-345P.

In any case, this is simply a standard cylindrical equal-area projection with standard parallels chosen to make the whole map area square.

Code

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

Use the supplied World dataset (in lat-lon EPSG 4326) and project as required!

Code

data("World") 
world_tc <- World %>%
  select(geometry) %>%
  st_transform("+proj=cea lat_ts=55.654")

tm_shape(world_tc, 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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