Thursday, August 11, 2022

Poor old Mercator!

 Stanley - Thursday

Poor old Gerardus Mercator.

We, of course, know him for his maps that most kids in the world have used in their geography classes. They are all something like this.

Map of the world - Mercator projection

Today, however, he is being criticised for being Eurocentric and racist because the projection distorts parts of the globe, minimising the size, for example, of Africa. If you look at the map above, Greenland looks to be about half of the size of Africa. In reality, Africa is fourteen times the size of Greenland. Similarly, Russia looks bigger than Africa, except it is actually just over half the size (17.1 million sq. km. versus  30.37 million sq. km. ).

Most readers will have seen the graphic below, which shows all the countries that could fit inside Africa.



The reality is that Mercator developed the projection for the sole purpose of helping ships navigate using only a compass. And in doing so distorted the sizes of countries - making those farthest from the equator relatively bigger and those closer to the equator relatively smaller. Doing this allowed ships to follow a constant bearing from one place to another. This is called a rhumb line.

You may be asking why he had to distort the map in the first place? The answer is that it is impossible to create a flat map of earth that maintains both size and shape.

If you were to put circles of equal size on a globe, then project them onto a flat surface using Mercator's projection, the circles would look like this.


That's why Africa looks so small and Greenland so big.

While the Mercator project distorts the size of countries, it does preserve their shape (which isn't particularly useful for maritime navigation!).

About fifty years ago, some people started questioning the implications of the Mercator projection from a social perspective. Why are the European countries so big relative to African countries? Big is usually associated with power and strength, so doesn't distorting countries this way give kids an incorrect perception of the power, both military and political, of these countries?

Why are Western countries at the top of the map? Doesn't that give observers a feeling of that the top ones are superior and those at the bottom of the map inferior?

I think these are reasonable questions to ask. However, to accuse Mercator of pushing a social agenda with his map is ridiculous.

One of the people pushing this perspective was German film maker, Arno Peters. He developed a projection that generally maintained the size of countries but not their shape.

This is a map using the Peters projection of equal-sized circles. You can see clearly the differences in distortion compared to Mercator.




On a normal map, it looks like this.




In fact, Peters' projection had been developed over a hundred years earlier by the Rev. James Gall in Scotland. The projection is now known as the Gall-Peters projection.

A lot of people have taken Peter's (and others') arguments seriously, and now the Mercator projection is banned in in a number of school districts in the USA and by UNESCO. In its place is the Gall-Peters projection.

(What maps are used in countries outside the USA? Readers please chime in.)

The reality is that it is impossible to project a globe onto a plane without distortion. This is a useful short video that explains these problems.

There are actually hundreds of different map projections, each useful for a specific purpose - accurate for that purpose, and inaccurate for most others.

Even when i was young, I had a problem with globes.


If you take a close look at a globe, it is obvious that most of the land mass is in what we call the northern hemisphere.

How is that possible? With the earth spinning, you would think it would be at the equator.

Sixty or so years ago when I first noticed this, I had no social implications in my head. My concern was more practical. 

Dirt and rocks are heavier than water. Right? So, since there is obviously more dirt and rocks in the northern hemisphere, it has to be heavier than the southern hemisphere. Right? And since heavier things sink to the bottom, what we call the northern hemisphere should be at the bottom of the globe. Right? So why is it at the top?

As I became more socially aware, I began to resent the fact that South Africa was at the bottom of all maps. That, together with the weight issue, made me look around. And this is what I found.




Much better - even though it has distortions. I like this perspective.

And here is a different focus. It has a very different feel to it.


You may have noticed that Google Maps, for example, still uses the Mercator projection even though country sizes are wrong. Why is this?

It boils down to the fact that when using a GPS, you are looking at a minute part of a country - so small, in fact, that the distortion is irrelevant. And since the country shape is preserved, the map on the GPS is so close to reality to be not worth worrying about.

So, to get back where I started, I feel sympathy for Gerardus Mercator, unfairly blamed for all sorts of social crimes. However, his maps have caused reasonable questions to be raised. They deserve a debate.

During my research for this article, I found many videos of interest.

This one is a pretty good one about map projections and their problems.

And this one, despite a few errors, is an entertaining one from West Wing.

_____________________________________________

September events:

 

Launch of A Deadly Covenant

 

Wednesday, 7. 4:30 – 5:30 pm 

Totally Criminal Cocktail Hour at Valley Bookstore

The Zephyr Theatre, 601 N Main St, StillwaterMN 55082

Find out more about the event HERE.

 

Friday, 9, 1:45 – 2:30 pm 

BOUCHERCON Panel:

The Mystery of Multiple Points of View and Multiple Timelines (Writers use dual perspectives/multiple narrators and alternating timelines to tell their stories.)

Marty Ambrose; William Boyle; Mary R. Davidsaver; B.A. Shapiro; Julie Carrick Dalton; Stanley Trollip (Moderator)

Saturday, 10, 11:30 -12:15 pm 

BOUCHERCON Panel:

Under the Sun or Below Zero (You’ve heard of “setting as a character.” Well … what about the weather?  These authors’ works represent a dichotomy of climates where rising temps or bone-chilling cold are just as effective as any villain.)

Alexander McCall Smith; Stan Trollip (Michael Stanley); Catriona McPherson; Jo Nesbø ; Matthew Goldman (Moderator); Caro Ramsay

Thursday, 15, 12:30 – 1:00 pm (UK time) 

Virtual event at the International Agatha Christie Festival

Agatha in Africa

Michael, Stanley and Zimbabwe author Bryony Rheam discuss Agatha Christie’s trip to South Africa and Southern Rhodesia and its connection with her mystery thriller The Man in the Brown Suit.

 

Monday 19, 6:00 pm 

Nokomis Library event

5100 S 34th Ave, Minneapolis, MN 55417 Phone: 612-543-6800

 

Wednesday 21, 6:00 pm 

Thomas St. Angelo Public Library of Cumberland event

1305 2nd Ave, Cumberland, WI 54829. Phone: 715-822-2767

 

Thursday 22, 6:30 pm 

Spooner Library event

421 High St, Spooner, WI 54801 Phone. 715-635-2792

 

Saturday 24, 1200

The Bookstore at Fitger’s

600 East Superior Street, Duluth MN 55802


Tuesday, 27, 6:00 pm 

Launch of A Deadly Covenant at Once Upon A Crime

604 W. 26th Street, MinneapolisMN 5540 Phone: 612.870.3785 Email: onceuponacrimebooks@gmail.com

With Mary Ann Grossman

October events:

 

Saturday 1, 9:00 am – 3:00 pm

Meet us at the Deep Valley Book Festival

Mankato, MN

Free book festival. We’ll be there from 9am to 3pm. The event takes place at the WOW! Zone, conveniently located at 2030 Adams Street in Mankato, just off Highway 14.

 

Thursday 6, 7:00 pm

Barnes and Noble HarMar

2100 Snelling Ave N, Roseville, MN 55113

 

Saturday 8. 

The Poisoned Pen Bookstore

4014 N Goldwater Blvd #101, Scottsdale, AZ 85251 Phone:(480) 947-2974 Toll Free: (888) 560-9919 Email: sales@poisonedpen.com

Stanley joins Barbara Peters on Saturday afternoon to chat about A Deadly Covenant.

 

Friday, 14, 10 am 

Lake Country Booksellers event

4766 Washington Ave, White Bear Lake, MN 55110 Phone: 651-426-0918

 

Saturday, 15, 10:00 am – 5:00 pm 

Twin Cities Book Festival

Minnesota State Fairgrounds, Saint Paul, Minnesota


2 comments:

  1. It all comes down to some interesting mathematics - essentially spheres and planes are intrinsically different. You just can't make them "look" the same in a smooth way. After that, it comes down to what distortion you want to live with.

    ReplyDelete
  2. I didn't know all of this and loved learning about it, Thank You!

    ReplyDelete