Your country may be smaller than you think
December 6, 2021 4:36 AM   Subscribe

This post was deleted for the following reason: Poster's Request -- loup



 
Oh this is neat! There are lots of cool projections other than Mercator that do a better job of preserving relative area (at the expense of other distortions, of course), but as technology moves into more and more personal and educational spaces, it totally makes sense to explore how maps can be presented differently when you have a dynamic screen.
posted by solotoro at 4:59 AM on December 6, 2021 [2 favorites]


Obligatory xkcd link.
posted by heyitsgogi at 5:08 AM on December 6, 2021 [28 favorites]


I've known about the distortions since childhood but this hits home in a way that's kind of shocking. I mean, I remember a childhood classroom having one of these maps and the teacher mentioning that it was more accurate projection but even with that, I didn't expect the differences to be so stark. Even though I know it's wrong, the Mercator projection is deeply ingrained.
posted by suetanvil at 5:11 AM on December 6, 2021 [2 favorites]


Pretty cool. This also shows how countries at extreme Southern latitudes have similar distortions and why it isn't such a big deal as the Northern ones - there just isn't that much land in extreme latitudes of the Southern hemisphere as both South America and Africa naturally taper, South America (which extends way further South than Africa does) even more so than Africa.
posted by atrazine at 5:13 AM on December 6, 2021 [2 favorites]


Supplementary xkcd link.
posted by logicpunk at 5:14 AM on December 6, 2021 [10 favorites]


I grew up with a globe in my childhood bedroom, so I took in fairly early the relative sizes of landmasses. I hadn’t quite understood how rare that was until my son got a globe as a gift from my parents when he was five that I realized that this was probably the first globe he had seen. Meanwhile, Mercator Projection maps are everywhere.
posted by Kattullus at 5:30 AM on December 6, 2021 [5 favorites]


I've internalized that England is about the size and shape of North Carolina while Ireland matches South Carolina. It helps.
posted by BobTheScientist at 5:31 AM on December 6, 2021 [2 favorites]


yay for being on the equator - we're always modestly sized and about to be engulfed by the rising sea!
posted by cendawanita at 5:36 AM on December 6, 2021 [7 favorites]


There was a nice chart of countries (or perhaps 'territories', given, eg the treatment of Alaska) sorted by size going around twitter the other day, but if you looked closely it had some very weird political biases. I think it was based on this.

I still don't understand the separation of Malaysia into West and East, but the twitter image certainly included the Crimea (absent in that link as far as I can tell), in the de facto rather than de jure country.

(I think the Twitter one also included Taiwan as part of the PRC)
posted by pompomtom at 5:41 AM on December 6, 2021


Yeah, but how many more times would the US have tried to invade Canada if it wasn't for Mercator intimidation?
posted by TheophileEscargot at 5:58 AM on December 6, 2021 [26 favorites]


Sweden is the rough size & shape of California, just rotated a bit (the state is ~2% smaller).
posted by Heywood Mogroot III at 6:07 AM on December 6, 2021 [1 favorite]


Obligatory West Wing link.
posted by mmoncur at 6:31 AM on December 6, 2021 [24 favorites]


This visualization is great because it shows the true sizes against their familiar locations with Mercator. We all have Mercator ingrained in us now thanks to slippy maps like Google Maps. The Mercator variant they use for that works very well for software so it's what we get.

By making other compromises you can make flat world maps that have equal area. The Equal Earth projection is a recent design that's quite nice; see the high resolution image here.
posted by Nelson at 6:42 AM on December 6, 2021 [5 favorites]


The Equal Earth projection is a recent design that's quite nice

I can see how that is a useful teaching tool for folks who weren't raised on Mercator, but tbh even though xkcd hates it, I personally get more use out of the rectangular ones like the Peters projection when I need to remind myself of actual size. My Mercator-ingrained brain sees the Equal Earth one and figures Canada and Russia are just tilted away from me, so their being smaller is just a matter of perspective.

As I've thought about this some more this morning, it would also be cool if someone made a similar gif but where near-equator countries got bigger ... The re-sizing being mostly focused on North America, Europe, and Russia, still in a way centers them as the important elements to be considered.
posted by solotoro at 6:59 AM on December 6, 2021 [4 favorites]


I still don't understand the separation of Malaysia into West and East

The East Malaysia political lobby is making inroads I see....

Speculation: it may be based on the fact that these are actually two quite distant land masses? But that makes no sense because Indonesian Kalimantan is happily grouped with the other islands of the country.
posted by cendawanita at 7:15 AM on December 6, 2021 [5 favorites]


I've internalized that England is about the size and shape of North Carolina while Ireland matches South Carolina. It helps.

This is exactly the flavor of dangerous talk that sounds benign but ends up inciting some needless Transatlantic BBQ-off.
posted by thivaia at 7:33 AM on December 6, 2021 [14 favorites]


This is exactly the flavor of dangerous talk that sounds benign but ends up inciting some needless Transatlantic BBQ-off.

Nobody knows The Troubles we'd see.
posted by thecincinnatikid at 7:57 AM on December 6, 2021 [9 favorites]


Nobody knows The Troubles we'd see.

Well, they'll involve plenty of mustard if South Carolina has anything to do with it.
posted by thivaia at 8:00 AM on December 6, 2021 [3 favorites]


Oh, it's a static map. I thought it was going to be this dynamic one from Engaging Data, which shows the Mercator-map countries shrinking to their actual size. Keep clicking to watch them inflate and deflate in step with Northern-hemisphere egos!
posted by rory at 8:00 AM on December 6, 2021 [6 favorites]


Many years ago, when we first traveled Brazil, was the first time I truly digested the fact that Brazil is actually larger than the contiguous US - and this really puts in stark contrast just how large Brazil really is vs all its global neighbors.
posted by thecincinnatikid at 8:02 AM on December 6, 2021 [5 favorites]


Oh, it's a static map

TLDR: keep scrolling ....
posted by thecincinnatikid at 8:13 AM on December 6, 2021 [3 favorites]


Even though I know it's wrong, the Mercator projection is deeply ingrained.

It's important to remember that all projections are equally wrong. All you can do, when projecting a sphere onto a flat surface, is choose what kind of wrong you want to be. You can be wrong about area, wrong about distance or wrong about contiguity. It's been said plenty of times before, but I can't help but feel that Arno Peters did real harm to the process of critically engaging public consciousness with the problem of projection by representing the Mercator projection as pernicious political propagand and Gall's projection as the truth They don't want you to see.

This piece would be much better if it included other projections, including equal area ones, to show the different kinds of distortions they introduce, and why you might choose one or another depending on your purpose.

Also there should be more globe beach balls. Maybe somewhere could introduce an educational tax break for all balls that feature an accurate rendition of continents and countries.
posted by howfar at 8:13 AM on December 6, 2021 [24 favorites]


Mercator projections and
Daylight Savings Time,
Miles V Kilometers, and
Sans Serif fonts.

Things keep getting better.

Yay.
posted by mule98J at 8:27 AM on December 6, 2021 [2 favorites]


I always liked the interactive version at The True Size where you can drag countries around the Mercator projection to see how they grow/shrink.
posted by indexy at 8:43 AM on December 6, 2021 [6 favorites]


Also there should be more globe beach balls.

This is brilliant!
posted by Atom Eyes at 9:08 AM on December 6, 2021 [1 favorite]


I've internalized that England is about the size and shape of North Carolina while Ireland matches South Carolina. It helps.

This is exactly the flavor of dangerous talk that sounds benign but ends up inciting some needless Transatlantic BBQ-off.

Nobody knows The Troubles we'd see.

Well, they'll involve plenty of mustard if South Carolina has anything to do with it.



Now I'm curious as to whether the regional Torquay BBQ tradition favors a dry rub or a marinade, and whether Galway is west enough that its BBQ heritage embraces a Western-style sweet sauce...
posted by darkstar at 9:24 AM on December 6, 2021 [3 favorites]


This is brilliant. I wish I had it when I was teaching Geography.
I do have a globe beach ball. It was helpful for teaching the difference between longitude and latitude. I could just draw on it... who would care? It's still a beach ball!

I also did a thing where I asked kids to draw a map of the work on an orange. Then they peeled the orange and tried to make it flat. What happened to the map of the world? It got distorted.
posted by dfm500 at 9:38 AM on December 6, 2021 [9 favorites]


Mercator mapping unprojections, daylight savings time.
Miles and kilometers, sans serif all the time.
Ten competing standards, bounding boxes, civil war.
Forums for the forums where we argue for ten more.

There it is again, that funny feeling...
posted by kaibutsu at 10:14 AM on December 6, 2021 [3 favorites]


regional Torquay BBQ tradition favors a dry rub or a marinade

The traditional flavourings are paraffin and burnt but I'm not sure how you marinate a beefburger without it falling apart.
posted by howfar at 10:27 AM on December 6, 2021 [4 favorites]


Another interactive map - Enter the desired country name in the field, then once it's highlighted you can drag it hither and yon across the map.

[whoops, I missed indexy had already linked to it...sorry!]
posted by Greg_Ace at 10:28 AM on December 6, 2021 [1 favorite]


I'd love to see this with the countries joined up, so I can see the distance between places- eg between Italy/North Africa and UK/Europe.
posted by Braeburn at 10:42 AM on December 6, 2021 [1 favorite]


I always liked the interactive version at The True Size where you can drag countries around the Mercator projection to see how they grow/shrink.

This one is really good. Makes it really easy to see stuff like Peru is not just larger than California, but larger than the entire west coast (Washington, Oregon, and California) of the USA. And Columbia is almost as big as Peru. Venezuela is the size of Texas.
posted by straight at 10:43 AM on December 6, 2021


I do have a globe beach ball. It was helpful for teaching the difference between longitude and latitude. I could just draw on it... who would care? It's still a beach ball!

I used to teach probability using a globe beachball. You have the kids throw the ball to each other, and when they catch it, they have to tell you where their two thumbs are touching: land or water. After 50 throws you get 100 thumbs. You'll always get about a 30/70 split. Because 70% of the globe is covered in water.

You can tell them ahead of time that it'll be this number, and then when they actually do it and see the result, it's like a magic trick, except it's better, it's math.
posted by nushustu at 10:47 AM on December 6, 2021 [29 favorites]


But after seing this will dreams still stay with you like a lover's voice fires the mountainside?
posted by Abehammerb Lincoln at 11:06 AM on December 6, 2021 [3 favorites]


nushustu: After 50 throws you get 100 thumbs.
I guess it's bonus points if one or other thumb is on Monte Carlo.
posted by BobTheScientist at 11:09 AM on December 6, 2021 [9 favorites]


The traditional flavourings are
British barbecue? It’s got to be tikka masala. And chips.
posted by Fiasco da Gama at 11:37 AM on December 6, 2021 [3 favorites]


You let the chips go cold for barbecue. This is called "potato salad".
posted by howfar at 12:23 PM on December 6, 2021 [2 favorites]


I kind of just want to take all the dark parts and stick them together, and call it the "stupid projection." Yeah, it wouldn't be "accurate" like a real Mercator projection, but nobody uses flat maps for navigating anyway. Also, the earth isn't even a sphere, and map people—they must have some sort of name, let's call them "practical topologists"—care lots about that.

Back when Google maps was a thing you used on a web page and phones still had buttons, I used to use "how would you implement Google maps" as an interview question for software developers. There's lots of places to explore how someone approaches problems, when the stack goes from the browser all the way to satellite imagery. And it's something most people had used at the time but hadn't thought much about precisely how you could make one of those yourself, and the problems you'd need to solve.

I prefer interview questions that touch on subjects that are actually likely to come up in the job, so at that time, unless I'm working at Google or Microsoft, this is a really unlikely problem area to actually come up, right? For instance, I was interviewing candidates to work on the software development team for a tabletop roleplaying game company—you know, lots and lots of dice, and rulebooks with hundreds of pages of tables on how to be an elf. So really, the whole "how would you build Google maps in a web browser" is more akin to "How would you build Flickr?", which was one of my other go-to questions in those days.

Except... Earth isn't the only planet people might want to explore via an interactive map. If you have a tabletop roleplaying game, you need a setting, a default place where all the rules take place. If your game has elves, then you need to explain, in one form or another, why it has elves and what they're up to, generally speaking. It's up to the players to make it happen, and there is one player in particular, the one that runs the game, and controls the non-player characters, like monsters, who generally shapes the world and the narrative.

But to explain the rules, you need a setting. And before you know it, you end up with an entire planet full of continents and oceans and countries and rivers and cities and mountain ranges and seaports and deserts and landlocked seas. This helps you assign projects to freelancers, because now you have a shorthand ("put it in the desert kingdom that's like Egypt with dragons"). And players like it too, because in addition to your rules, you also publish adventures. These are prebuilt set pieces, which you can combine and present to the players, with plots, maps, monsters, memorable characters, etc. If people like an adventure, you can set more adventures in the same area. Entire series of adventures may have the player characters roaming to and fro across an entire region, handling conflicts that involve the leaders of entire nations.

These adventures need maps. You don't strictly need the maps for the basic setting for the game rules, because the presumption is that the players can make their own maps. But once you publish an adventure, you need to provide a map. And if you're publishing an entire series of adventures across an entire region, you need more maps, that cover larger areas. Naturally you are also collecting these maps into other products such as "guide to the region of the record-collecting ants", which means more maps.

These maps are made by cartographers, but they're not ordinary "practical topology"-type cartographers. They're visual artists, more akin to illustrators. They typically use Photoshop or something like it, though there are some tools aimed at making it easier to work with gridded layers, repeating textures, landscape generation, etc.

Practical topology-type cartographers have extremely specialized, extremely mathematical software tools, and enormous databases of mapped points. It's an extremely rigorous field, these are the sort of people that would really prefer if everything had sixteen places after the decimal, and put careful thought into picking the projection they're going to use for basically any map, even one that's just a few miles across. Because it turns out, that's enough to actually warp the surface of your map enough that you have to take it into account when drawing a diagonal line from one corner to the other.

I actually had a couple different use cases for the Google maps question, but the obvious one is: Let's make a Google maps for our default setting. Which, come on, super awesome to have. Of course, there's a lot of ground to cover on an entire planet, so you might not have great maps of the entire thing. But let's say you have enough maps to cover the important areas. The next step is, take all that "satellite imagery" and rescan it at varying resolutions, and then chop it up into little square tiles that you can swap in quickly. That way you don't have to download the entire map, just the portion you can see.

The other use case I had for this technology was, take the map of a dungeon, and zoom and tile it for use in a virtual tabletop. The virtual tabletop takes all the game stuff and jams it into a web browser. In this case, since we have print-resolution maps, we can zoom up to 8 steps, from the overall view of the market square, down to close enough you can literally see the individual illustrated fruit in the carts. This actually worked ridiculously well, and later I adapted the same idea for rapid-viewing individual pages of a PDF. For that, of course, you want a straight one-to-one projection, because you are mapping a plane to a plane. Not a sphere to a plane. So the mapping you choose for presenting a tactical map of a dungeon is the same for the printed page: No warping at all, because the source and destination are both flat. Just scaled differently.

But for Google maps, you absolutely need the projection, because the thing you are displaying, and the thing you are projecting it onto, are two different shapes. And, because humans are awesome, we know to do things like adjust differently because the Earth bulges out a little bit at the equator. But we'll ignore that for the imaginary world.

Guess which kind of cartographer doesn't actually use projections from a sphere to a flat space when drawing maps of large portions of a globe? Right, people doing what they're supposed to, which is make things people want to pay money for. These maps look fantastic on the printed page, or vinyl map, or poster, but they're not really practical topography...

Anyway, all that map-related stuff got set aside for other priorities, but to do it properly for an imaginary planet, from a bunch of flat maps, you need to do the exact kind of map projecting that you get with the Mercator, except backwards.
posted by bigbigdog at 12:56 PM on December 6, 2021 [11 favorites]


The thing I like about this is that it makes me reconsider northern Canada. I had more-or-less internalized that Mercator Greenland was much larger than actual Greenland and so it wasn't nearly as big as one might think.

However, I never applied that to Nunavut! I hold northern Canada in this sort of religious awe as a massive no-man's land where humans have barely trodden, but Ellesmere Island is more like the size of New England than the size of Siberia.
posted by xthlc at 2:24 PM on December 6, 2021 [7 favorites]


Wow. I had a general intellectual awareness that northern countries were exaggerated in the maps I was used to, but I truly had no idea to this degree. Thanks for the link!
posted by obfuscation at 3:04 PM on December 6, 2021 [1 favorite]


I've internalized that England is about the size and shape of North Carolina
I have a bunch of these in the back of my mind; but I wonder which ones might need updating for population?
New York City is the size of London, while New York State is the physical size of England. But England contains 35 million more people.
New Jersey is the same size and population as Israel. New Jersey is also shaped a bit like a tiny reversed California.
Canada is California, minus 10 million people. Australia is Canada, minus 10 million people.
That dangly bit on the map of Canada between the Great lakes, going from Quebec City to Hamilton? Half of Canada's population lives there.
People joke that it's the 'Texas of Canada'; but there are twice as many people in the Dallas-Fort Worth metroplex as there are in all of Alberta.
Mexico has the population of Japan.
The city limits of Tokyo and Mexico City both contain 10 million people. (Tokyo's metro area is bigger than CDMX's tho.)
There are a billion people in The Americas.
There are a billion people in Africa.
There are a billion people in India, which is about the size of the USA between the Rocky Mountains and the Mississippi River.
Cuba is the size of Tennessee, with twice the population.
It takes five Australias to cover the Moon; the Moon is one Australia in diameter.
posted by bartleby at 7:06 PM on December 6, 2021 [10 favorites]


One of my GIS instructors had an area projection map centred on Africa with South up hung in his office. It didn't even look like Earth even after you figured out what was being displayed.
posted by Mitheral at 7:55 PM on December 6, 2021 [1 favorite]


Here's my favorite one: The moon has about the same surface area as Africa and Australia. (Africa is really, really big.)
posted by nushustu at 10:25 PM on December 6, 2021 [2 favorites]


bartleby: It takes five Australias

Australiae?

nushustu: (Africa is really, really big.)

It really is... and the fact that I once rode right across it on my motorbike, from west to east, fills me with awe at my 32-years old badass self. In some ways wish I was still that person.

We cut across one of the bends in the Nile; it was 300 kms, an easy one or two day piste depending on your speed. Small potatoes.
Suddenly it dawned on me that those 300 kms are the length of my entire home country. I will gladly concede that I live in a small country... but Africa is really, really big.
posted by Too-Ticky at 12:47 AM on December 7, 2021 [6 favorites]


the Mercator projection as pernicious political propagand and Gall's projection as the truth They don't want you to see

Pfft. Neither of those shows the ice wall properly.
posted by flabdablet at 4:58 AM on December 7, 2021


The Mercator projection does get dumped on a lot because of its area distortions with latitude - and rightfully so, but it should be noted that the Mercator projection was uniquely useful to navigators. What you can do as a navigator is to place a ruler on the projection from where you are to where you want to be, measure the angle (say, south by south west), and then all you need to do is sail your ship on that bearing and you will arrive at your destination via the shortest possible route (i.e. a great circle). You can't do that with any other projection except for a Globe. Thus, it's not really for reasons of say, Western imperialism that the Mercator projection became the "default" during the 19th century - it's far more to do with its usefulness as a tool to get from A to B.
posted by BigCalm at 6:45 AM on December 7, 2021 [6 favorites]


Mercator is indeed good for long distance navigation but not quite as perfect as that. A straight line on a Mercator map is a rhumb line, which means you can set a constant bearing (your SSW) and get to the destination. But a rhumb line is not a great circle, not the shortest path.

The difference in path length isn't a big deal considering the navigation inaccuracies inherent in 17th century long distance sailing. But it is significant for flying. Modern aviation charts in the US use a Lambert conformal projection; straight lines on that projection do "approximate" a great circle. I'm not sure what the deviance is, but I do remember learning the tedious method of actually plotting and navigating a great circle route. It's a straight line on the piece of paper but when you're flying you have to update your bearing every few minutes to track it.

Now I'm wondering what other projections have straight lines of constant bearing. Naively I'd thought any conformal projection would have that property, but that's not right. A quick Google search turns up the fairly obscure loximuthal projection (demo here). Not sure of the properties of this one. It's parameterized by a reference latitude, which is useful when making customized local maps. But it's quite different from Mercator in shape.

All projections are compromises. It's interesting how subtle a concept they are.
posted by Nelson at 7:54 AM on December 7, 2021 [2 favorites]


Thus, it's not really for reasons of say, Western imperialism that the Mercator projection became the "default" during the 19th century - it's far more to do with its usefulness as a tool to get from A to B.

Except that the reason anyone cared about getting from point A to B efficiently is ... colonialism. Gotta ship supplies to/from Blighty at greatest speed/lowest cost, particularly for things that were likely to spoil like spices and fruits. Long distance trade has been a thing since cavepeople, but even Roman-era maps, while still imperial in design (all roads lead to Rome, literally) are distinctly different from Mercator and its derivatives.
posted by basalganglia at 9:04 AM on December 7, 2021 [5 favorites]


MapFrappe is a service I love: draw a line around any geographic area on one side and drop it elsewhere on the globe on the other side.
posted by St. Oops at 4:25 AM on December 8, 2021


Reimagining projections for the interactive maps era (MapBox engineering blog).
posted by Nelson at 10:18 AM on December 9, 2021 [1 favorite]


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