Why is Africa the way it is?
Why are its countries where they are?
The relationships between them
The people? The deserts?

Here are X to easily understand Africa better (politics, geography, history, demographics, climate & more)
One of the key ways to look at Africa is through this map: its river basins.

Let's start with the big one in the northeast. It's the Nile's watershed.
Here's northeast Africa at night. See that flower in the middle? That's the Nile through Egypt.
100 million Egyptians live within ~15 miles of its banks. That's ~99% of them.
More details here.

Because all the rest is just desert. The Sahara. But why is the Sahara where it is? Because of Horse Latitudes
Across the world, at that latitude—called horse latitude—there are hot deserts.
But why?
Because of winds
The equator is so hot that air goes high up in the atmosphere, where it gets cold and its water falls.
Due to the size of the earth, that air falls down at the horse latitudes. Dry air falling means no rain.
Morocco, Algeria, and Tunisia are just at the limit of Horse Latitudes, have humidity from the Mediterranean sea, and the Atlas mountains condensate the water from the wind. So there's enough water on the north of the Atlas mountain range—so ppl—but nothing south.
That sliver of green in Northwest Africa hosts 92M Africans.
But farther east it's too far south into the Horse Latitudes, so even if Libya is bigger than Morocco, Tunisia, and Egypt combined, it only has 5M ppl!
If you look at the river basins in the Sahara, you can see few of these rivers end in the sea: they dry up before they arrive.
Only the Nile manages to cross the Sahara. In fact, it's so unique, it's the longest north-south river in the world.
But where is it born? The Nile is the combination of the White Nile from Lake Victoria, in the middle of Africa, and the Blue Nile, from Ethiopia.

What ppl don't know is that ~90% of the water of the Nile comes from Ethiopia!

Again, because of rains, obviously
It makes sense that the equator has so much rain, but why Ethiopia? Because of its highlands
Ethiopia's highlands are super high, so they catch all the water from the winds blowing into it.
Here's a closeup of the Ethiopian Highlands. Very high
Why does Ethiopia have so much rain but Somalia is so dry? Because once winds pass Ethiopia, they're empty of water. It's called the rain shadow effect.
But why do winds blow in this direction in Africa, from west to east, and not the other way around? Because of the monsoon winds.
In june-sept, winds blow from the Atlantic towards Africa, bathing the continent with water.
In dec-mar, when the hottest part is farther south, they blow from the Indian Ocean.
That's why Somalia is dry: by the time the jun-sep winds reach it, all the water fell in the Ethiopian highlands.

It's also why the Kalahari (esp Namibia) and the west of South Africa are so dry: by the time eastern winds arrive in jan-mar, all their water has already fallen
Obviously, the more rain, the more food, the more ppl. That's why the map of water precipitation in Africa matches the map of population density pretty well
Except for that hole in the middle. What is that?
Around the equator, land is actually not fertile at all. It's so hot and humid that plants and animals recycle waste extremely fast, before sediments litter the floor. And then rain washes away any potential fertilizer
That's why the same thing happens at the Amazon in America: it's not fertile land, and few live there.

So although the Congo (middle green) is huge and has lots of water, it "only" has 90M ppl (to Nigeria's 200M)

But why are there so many mountains stopping rains across Africa?
Because of the Rift Valley: 2 mountain ranges with a valley in the middle that cross Africa.

These are the mountains that stop all the monsoon water that later become so many rivers, including the Nile.

And why is the Rift Valley there? Because of plate tectonics.
Africa is splitting in two in the Rift Valley. The plates are separating at that level. Central African lakes Victoria, Tanganyka, Malawi, and others are just the central Rift valley trapping water from the 2 mountain ranges on the sides
So there you are: the earth's plate tectonics and size cause Africa's mountains and winds, which cause the continent's geography, and create all these climates where humans thrive—or not:
- Egypt's Nile feeds 100M ppl
- Morocco, Algeria, Tunisia are the Med coast above the Atlas
- Libya is nothing because it has no water. Same as most Saharan countries
- The few Saharan countries that survive live around internal lakes: eg Chad / Niger around Lake Chad
- Ethiopia's highlands catch wind's water, which supports 120M ppl
- But Somalia has none left, so it's desert
- The Rift Valley creates rivers and lakes that can feed populations: Uganda, Rwanda, Burundi, Malawi, Zimbabwe..
- Tanzania, Kenya, Mozambique, and South Africa get enough water from eastern monsoon winds that they can support big pops
- Namibia doesn't, so it's desertic. Southern Angola isn't great either. But the north could have a bigger population
- Congo: too hot and humid to be fertile, so its population is limited.
- But the West Africa pop is huge: it has humidity + heat w/o too much as the Congo. That's all the countries btw Senegal & Nigeria

I go into more detail on all of this in this week’s article
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More from @tomaspueyo

14 Oct
Parag and I talked for over an hour about migration and the impact it will have in the 21st century. We covered:

- How current nationalism & the image of immigration is short-sighted historically
- The + borders you have, the - borders you have
- The existence of empires today
- African pop growth is overestimated
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Read 6 tweets
6 Oct
Ireland's future is at stake.

This Friday, there is a an important OECD meeting to debate the global minimum corporate tax rate.

These are the stakes for Ireland:
Countries like the US want *at least* 15% global corporate tax.
A few months back, 130 countries reached an early agreement. A handful of others didn't join. At their head was Ireland. Why?
The richest (GDP per capita) country in Europe is *Ireland*. Richer than Germany, richer than Luxembourg, richer than Switzerland.

At 117% of US GDP per capita, Ireland is a whopping 31 percentage points richer than the next big European country, Netherlands, at 86% of US GDPpc
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28 Sep
The end of nation-states is coming.
Internet and Blockchain will bankrupt them, by distributing its power to individuals, corporations, supra-national entities, and distributed organizations.

Just at the moment when they need more $ than ever
Thread 🧵
Picture this:
1. Individuals have + power.
They can access all the info in the world, and reach everybody in the world. The only thing they need is good, catchy ideas.

A single person, Satoshi Nakamoto changed the world with a pseudonym with their Bitcoin paper.

QAnon did the same
Read 35 tweets
24 Sep
The geography of Egypt is bonkers 🇪🇬🌍
Look at that image of the Middle-East by night. See that "flower" in the middle? That is the Nile.

Egypt has 105 MILLION ppl!
99% of them live in that light area!
That's 3% of its territory!

What else is crazy about Egypt's geography?
The Nile's banks are between 0.5km and 20km wide (~0.3 to 12 miles). 105M ppl live in that area plus the delta. Crazy. They do that because it's fertile AF

What's outside though? Nothing.
In the west, there's nothing for thousands of miles. There's so much nothing that in 5000 years of history, Egypt has NEVER been successfully invaded from here.

Even the nazis tried and failed.
Read 19 tweets
23 Sep
“The future is already here. It’s just not evenly distributed.”—William Gibson @GreatDismal

The future is already in the brain of the 200 million cryptocurrency holders. They can be better understood as a country, as an alternative community to nation-states.
A nation-state citizen doesn’t question the sovereignty of the gov
Doesn’t question the validity of its currency
Doesn’t fathom a world without the TVs and radio stations and notary-publics and certification organisms that make the nation-state what it is.
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They can’t fathom the end of the nation-state, just as 1500s-era Europeans couldn’t fathom the end of the omnipotent Catholic Church.
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20 Sep
The emergence of cryptocurrencies reminds me of the emergence of writing and currencies. These are obvious to us now, but they were weird to their contemporaries.

Let's have a look 🧵
The parallel with fiat currencies is better known, so let's start with it.

Early on, ppl bartered. Inconvenient.
So they started using some currency.
First, it was something scarce, easy to value and to divide into smaller pieces (=fungible), and with some intrinsic value. Eg, salt (thus "salary")
Read 24 tweets

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