The true true size of Africa – Cartography

 

Click to the picture for higher resolution

LAST month Kai Krause, a computer-graphics guru, caused a stir with a map entitled “The True Size of Africa”, which showed the outlines of other countries crammed into the outline of the African continent.

His aim was to make “a small contribution in the fight against rampant Immappancy”—in particular, the fact that most people do not realise how much the ubiquitous Mercator projection distorts the relative sizes of countries.

A sphere cannot be represented on a flat plane without distortion, which means all map projections distort in one way or another. Some projections show areas accurately but distort distances or scales, for example; others preserve the shapes of countries but misrepresent their areas. You can read all the gory details on Wikipedia.

Gerardus Mercator’s projection, published in 1569, was immediately useful because it depicts a line of constant bearing as a straight line, which is handy for marine navigation.

The drawback is that it distorts the shapes and areas of large land masses, and the distortion gets progressively worse as you get closer to the poles.

(Africa looks about the same size as Greenland under the Mercator projection, for example, even though it is in fact 14 times bigger.) This was not a big problem for 16th-century sailors, of course, and the Mercator projection remains popular to this day.

In Mr Krause’s map (above) he seems to have used the shapes of the countries from a Mercator projection, but has scaled up the outline of Africa, without changing its shape, to show the appropriate area. An alternative and arguably more rigorous approach would be to repeat the exercise using an “equal area” projection that shows the countries’ areas correctly while minimising shape distortion.

These two properties are the hardest to balance when showing the whole world on one map. I decided to rework Mr Krause’s map using Gall’s Stereographic Cylindrical Projection (1855) with two standard parallels at 45°N and 45°S. Distortions are still evident at the poles, but for most countries shape is maintained, and their areas are shown correctly.

As you can see (below), the results are distinct from Mr Krause’s map. But however you look at it, his point is a good one: Africa is much bigger than it looks on most maps.

Advertisements

One thought on “The true true size of Africa – Cartography”

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Advertisements
My Daily Journal.........

Everything from my world to yours'......:)

The Perks of being Different

Just sharing some experiences :)

Exclusivito

Confessions of a book-traveller

Спектакли онлайн

Спектакли онлайн — блог Алексея Марковича, где автор выкладывает фото и видео спектаклей, поставленные по его произведениям. Алексей Маркович, 39 лет. Писатель, сценарист, переводчик, режиссёр театра SCI-FI THEATER (Орегон, США). Алексей проводит творческие вечера, на которых читает свои рассказы.

https://malimachhindra11.wordpress

मुखपृष्ठ मच्छिंद्र माळी

STORY OF STREET

WHERE EVERY CHARACTER IS A GEM AND EVERY MOVE IS A DREAM

Pen Paper and IT

This is my corner of the Net where I can relax and share my thoughts

Dear Dharma

Advice on almost anything…

Human Life Run

Mistakes Are Reality Of Life

BayArt

New Perspective on Life

mali9437

Machhindra wordpress

indahs: dive, travel & photography

cities - cultures - ocean - marine life

The Beauty Along the Road

Discovering Beauty in the small details of our lives

THE WORDSMITHSCRIBE--MLST

A personal comprehensive compendum of related personal thought, diary, articles geared towards championing and alleviating the course of humanity towards the achievement of a greater society whereby all the inhabitants of the world are seeing as one and treated equally without any division along religious affinity, social class and tribal affliation.This is all about creating a platform where everybody interested in the betterment of the society will have a voice in the scheme of things going on in the larger society.This is an outcome of deep yearning of the author to have his voice heard across the globe.The change needed by all and sundry all over the globe starts with us individually.Our world will be a better place if every effort at our disposal is geared towards taking a little simple step that rally around thinking outside the box.

vtofighi

A great WordPress.com site

Ashes of Life

A journey to discover my own writing voice

The Blog of Travel

Motorbikes, dogs and a lot of traveling.

Advertisements
%d bloggers like this: