An area cartogram is a map that tries to convey information by resizing areas to show data, e.g population, domestic product or number of languages. There are several world population versions (and other data sets) by Sasi Group and Mark Newman available at Worldmapper.org. Those start off with something similar to a Gall-Peters Projection and then distort the individual countries or regions according to the data to be shown. Sometimes they can be quite comical by enlarging Alaska to imply that several tens of million people live there. The Humans Who Read Grammars blog recently asked me how to improve on Illustrating current questions in research on linguistic diversity. I thought of a cartogram I put together a while ago, which I was inspired to by Paul Breding’s and Chase Mohrmann’s cartograms.
Frank Jacobs at Strange Maps compares the 2004 version to 2014 version.
I am not that big of a fan of Gall-Peters or Mercator Projections and when I looked at Breding’s and Mohrman’s cartograms I had the impression that they tied themselves to these projections. Small little squares, representing 1 million or 0.5 million people form 8-bit rendered countries distorted depending on how densely populated they are and how far north or south. Breding attempted to keep the position of the countries and borders to each others. Take a look at China, India and Russia. China is so big it gets expanded into a rectangle reaching to the same longitude as western Turkey. India is recognisable but demands all neighbouring countries adapt to it. And Russia, snakes around China like a long C. Mohrman tried to fix some of this by keeping the shape of China and India. China is then place next to Russia but sits squarely on top of India. Indochina then is a peninsula that protrudes east. There had to be a better way to draw this.
We are not stuck with Mercator, there are other options, and one of these is a interrupted octant projection like the recently published Cahill-Keyes M-shape or Waterman‘s Butterfly. Plus in 2015, hexagons, seemed, to be, all the, rave. Why not combine these two and create a cartogram that improves the form and placement of countries. If squares were made for Mercator Projection cartograms then hexagons were made for octant projections.
The main angles of a hexagon grid line up with the angles of the “wings”.
This my concept for a world population cartogram.
I think it improves shape and placement of countries. India and China work out better than the Breding or Mohrman cartograms. In retrospect, China should have been placed further north so that Russia could have followed a more northern path with fewer hexagons necessary to reach towards Manchuria and Indochina would not have been pushed so far south. Manchuria, Tibet, Wales and Scotland are labelled, many metropolitan areas and islands as well. The Butterfly map which has been split and placed left and right (and bottom) is by Jason Davies. Davies has shared many different maps at jasondavies.com. The colours of individual countries in the smaller map match up those of the cartogram. I felt labelling everything would clutter the graphic and for exact numbers a table is better (or maybe and interactive infographic with pop up labels). I think it looks cluttered anyway, maybe I need to revise it. Bottom left I added a pie chart inspired by this but redid it with a better continent projections. Bottom right is graph showing population increase since 1800.
Now to program it to show data-sets.
- There is also a 2011 cartogram of the world population by Roger Schulz