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[QUICK THREAD: THE CURSE OF MAGDALENE]
1/27
Under normal weather conditions, although the jury's kinda out on what's "normal" anyway, it takes the elements 2,000 years to wash away 13 billion metric tons of soil in erosion.
A flood in July 1342 did it in a matter of days.
1/27
Under normal weather conditions, although the jury's kinda out on what's "normal" anyway, it takes the elements 2,000 years to wash away 13 billion metric tons of soil in erosion.
A flood in July 1342 did it in a matter of days.
2/27
After a protracted cold spell, a mini ice age of sorts, Europe started thawing in the spring of 1342. This created enough meltwater to flood almost every major river and lake in Europe.
And then came the rains.
After a protracted cold spell, a mini ice age of sorts, Europe started thawing in the spring of 1342. This created enough meltwater to flood almost every major river and lake in Europe.
And then came the rains.
4/27
The general thaw, you see, coincided with what's called a Genoa Low. Genoa Low is a cyclone that's born over the Ligurian Sea and dies over the Adriatic, some 2-3 times a year. Basically it carries seawater from Italy's west and pours it into its east.
The general thaw, you see, coincided with what's called a Genoa Low. Genoa Low is a cyclone that's born over the Ligurian Sea and dies over the Adriatic, some 2-3 times a year. Basically it carries seawater from Italy's west and pours it into its east.
5/27
Along the way, the cyclone dashes and brushes against the Alps and drops a bit of its payload over Italy as a result. Just like the monsoons do when they hit the Himalayas. Why Genoa Low? Because Genoa happens to be the largest city where the cyclone is born.
Along the way, the cyclone dashes and brushes against the Alps and drops a bit of its payload over Italy as a result. Just like the monsoons do when they hit the Himalayas. Why Genoa Low? Because Genoa happens to be the largest city where the cyclone is born.
6/27
One such Genoa Low hit right after the thawing of 1342. But this one carried a little more water than usual. The rains didn't last long. Hardly 10 weeks. But more water was poured on Europe during those 10 weeks than ever before. Or since.
One such Genoa Low hit right after the thawing of 1342. But this one carried a little more water than usual. The rains didn't last long. Hardly 10 weeks. But more water was poured on Europe during those 10 weeks than ever before. Or since.
7/27
The flood is said to have peaked around July 22, the feast of Mary Magdalene. And because of that, it got named after her: Magdalenenhochwasser (literally, Magdalene's high water) or St. Mary Magdalene's flood.
The flood is said to have peaked around July 22, the feast of Mary Magdalene. And because of that, it got named after her: Magdalenenhochwasser (literally, Magdalene's high water) or St. Mary Magdalene's flood.
8/27
Now Genoa Lows are no strangers to Europe, nor are the floods they bring. These cyclones have flooded the continent in 2014, 2013, 2009, and 2005, just to list a few. And these are only the major ones. So the flooding is expected.
But 1342 was different.
Now Genoa Lows are no strangers to Europe, nor are the floods they bring. These cyclones have flooded the continent in 2014, 2013, 2009, and 2005, just to list a few. And these are only the major ones. So the flooding is expected.
But 1342 was different.
9/27
Germany, by most medieval accounts, was the worst-hit thanks to the large number of rivers cutting through the country. Almost all major bridges were washed away and churches drowned, spire and all. One river, for instance, recorded water levels as high as 24 feet.
Germany, by most medieval accounts, was the worst-hit thanks to the large number of rivers cutting through the country. Almost all major bridges were washed away and churches drowned, spire and all. One river, for instance, recorded water levels as high as 24 feet.
10/27
Main, the river feeding cities like Frankfurt, moves a little over 26,400 gallons of water a second during a normal July. In 1342, this volume was well over a million gallons. Per second. This is rather rare, happening only once in 4,000 to 10,000 years.
Main, the river feeding cities like Frankfurt, moves a little over 26,400 gallons of water a second during a normal July. In 1342, this volume was well over a million gallons. Per second. This is rather rare, happening only once in 4,000 to 10,000 years.
11/27
See these food marks on a building near Hanover near the birthplace of river Weser in Lower Saxony. Starting at the bottom, the plates read Jan 1995, Nov 1926, 1890, Feb 1909, Feb 1946, May 1943, Jan 1841, Jan 1682, Jan 1551, Jan 1643, Jul 1342. HW stands for Hochwasser.
See these food marks on a building near Hanover near the birthplace of river Weser in Lower Saxony. Starting at the bottom, the plates read Jan 1995, Nov 1926, 1890, Feb 1909, Feb 1946, May 1943, Jan 1841, Jan 1682, Jan 1551, Jan 1643, Jul 1342. HW stands for Hochwasser.
15/27
The 1342 deluge was different not only in immediate damage but also in its long term aftermath. It's said a third of all soil erosion of past 1,500 years took place during this one-week window starting July 22, 1342. https://web.archive.org/web/20111230134322/http://www.nzz.ch/2005/08/25/il/articleD31CG.html
The 1342 deluge was different not only in immediate damage but also in its long term aftermath. It's said a third of all soil erosion of past 1,500 years took place during this one-week window starting July 22, 1342. https://web.archive.org/web/20111230134322/http://www.nzz.ch/2005/08/25/il/articleD31CG.html
16/27
This erosion was facilitated by, among many factors, terrible land management in medieval Europe. Today, about 30% of Germany is forested. Back in the day, it had hit a low of 10%. We need no lessons in what deforestation does to top soil, especially during a flood.
This erosion was facilitated by, among many factors, terrible land management in medieval Europe. Today, about 30% of Germany is forested. Back in the day, it had hit a low of 10%. We need no lessons in what deforestation does to top soil, especially during a flood.
17/27
Acres upon acres of what used to be fertile farmlands remain barren and non-arable to this day, many set to stay that way until the next glaciation period at least 10,000 years away.
Do note that this was less than 30 years since the Great Famine of 1315-17.
Acres upon acres of what used to be fertile farmlands remain barren and non-arable to this day, many set to stay that way until the next glaciation period at least 10,000 years away.
Do note that this was less than 30 years since the Great Famine of 1315-17.
18/27
The Great Famine had killed nearly 80% of all livestock and driven starved Europeans into measures like cannibalism. Less than 2 generations down the line was another climate crisis triggering another famine. But something worse than famine was in store this time.
The Great Famine had killed nearly 80% of all livestock and driven starved Europeans into measures like cannibalism. Less than 2 generations down the line was another climate crisis triggering another famine. But something worse than famine was in store this time.
19/27
Karakoram those days was the capital of the Mongol Empire. The Empire itself was divvied up among several nomadic dynasties, one of them called the Golden Horde. It was led by a Jani Beg. With an eye on Byzantium, this was the most ambitious of all Mongol hordes.
Karakoram those days was the capital of the Mongol Empire. The Empire itself was divvied up among several nomadic dynasties, one of them called the Golden Horde. It was led by a Jani Beg. With an eye on Byzantium, this was the most ambitious of all Mongol hordes.
20/27
The Byzantine Empire was then ruled by John VI Kantakouzenos who had a 13 year old son. One day in 1347, the boy suddenly fell sick.
And died.
Nobody knew what happened. Those days Constantinople was experiencing a heavy influx of people fleeing something.
The Byzantine Empire was then ruled by John VI Kantakouzenos who had a 13 year old son. One day in 1347, the boy suddenly fell sick.
And died.
Nobody knew what happened. Those days Constantinople was experiencing a heavy influx of people fleeing something.
21/27
Most of these refugees were from Genoa, mostly traders. Many of them were sick. With the same mystery disease that eventually killed the young prince. Something was going down in Genoa.
Well, not really. It was elsewhere.
Most of these refugees were from Genoa, mostly traders. Many of them were sick. With the same mystery disease that eventually killed the young prince. Something was going down in Genoa.
Well, not really. It was elsewhere.
22/27
These Genoese traders had all been in business with Crimea across the Black Sea. More specifically Kaffa, a Crimean port city. That's where something has happened some 2 years earlier.
A siege.
It was a Mongols.
The Golden Horde.
These Genoese traders had all been in business with Crimea across the Black Sea. More specifically Kaffa, a Crimean port city. That's where something has happened some 2 years earlier.
A siege.
It was a Mongols.
The Golden Horde.
23/27
During a protracted siege, the Mongol commanders came up with an ingenious idea. They had many people dropping dead with a mysterious curse. Apparently anyone who came in contact with the dead, died too. So that started catapulting these corpses over the city walls.
During a protracted siege, the Mongol commanders came up with an ingenious idea. They had many people dropping dead with a mysterious curse. Apparently anyone who came in contact with the dead, died too. So that started catapulting these corpses over the city walls.
24/27
As Kaffa townsfolk began dying, the siege drew shorter. But what was this curse?
These tribes had come from Central Asia. The region itself has recently come out of a very dramatic climate upheaval. After a long dry spell, there was a series of very wet summers.
As Kaffa townsfolk began dying, the siege drew shorter. But what was this curse?
These tribes had come from Central Asia. The region itself has recently come out of a very dramatic climate upheaval. After a long dry spell, there was a series of very wet summers.
25/27
The Karakoram, the Horde's base, experienced one of the worst onslaughts of this climate change. The first outcome of this spell was a famine. So people, being nomadic anyway, moved to greener pastures. Along the Sulk Route. Westward.
But they didn't move alone.
The Karakoram, the Horde's base, experienced one of the worst onslaughts of this climate change. The first outcome of this spell was a famine. So people, being nomadic anyway, moved to greener pastures. Along the Sulk Route. Westward.
But they didn't move alone.
26/27
Driven by food and vegetation shortage, animals moved too. Those who couldn't, perished. But many could. And did.
Most of the ones who did were rodents.
And many of them were pregnant with a mysterious bacteria.
This was 1345.
Driven by food and vegetation shortage, animals moved too. Those who couldn't, perished. But many could. And did.
Most of the ones who did were rodents.
And many of them were pregnant with a mysterious bacteria.
This was 1345.
27/27
By 1347, these bacteria were in Constantinople. And scored their first big-ticket casualty, the 13-year-old heir to the Byzantine throne.
The Black Death was finally in Europe.
By 1347, these bacteria were in Constantinople. And scored their first big-ticket casualty, the 13-year-old heir to the Byzantine throne.
The Black Death was finally in Europe.
