It’s a strange question, but hear me out: Have you ever wondered what would happen if the Mediterranean Sea disappeared?
Well, wonder no more, because about 5.5 million years ago, it did exactly that.
When the Mediterranean Sea Almost Vanished
No one alive today has ever known a world without the Mediterranean Sea. But, around 5.5 million years ago, the Mediterranean Sea faced a dramatic crisis.
Known as the Messinian Salinity Crisis (MSC), this event saw the Mediterranean largely cut off from the Atlantic Ocean, causing it to evaporate almost entirely.
How Did It Happen?
The cause of this dramatic event lies in the shifting of tectonic plates. Around this time, the African plate was moving northward, gradually closing the Strait of Gibraltar, the narrow passage that connects the Mediterranean to the Atlantic Ocean.
With the strait closed, water from the Atlantic could no longer flow into the Mediterranean, and as the climate warmed, the sea began to evaporate.
What Happened to the Sea?
As the waters receded, what remained was a vast, salty desert. Imagine standing at the bottom of a dry sea basin, surrounded by towering cliffs that once marked ancient coastlines.
Scientists believe that during this period, the Mediterranean Sea lost about 90% of its water. The remaining water was incredibly salty, with salt flats replacing the once-deep waters. In some places, the seabed was over a mile and a half below the current sea level.
The Mediterranean Desert
As the water evaporated, it left behind an extremely harsh environment. The Mediterranean basin became a scorching desert, with temperatures soaring and little to no fresh water available.
Many marine species that once thrived in the sea perished, unable to adapt to the rapidly changing conditions. The loss of water would have eventually led to the collapse of the Mediterranean marine ecosystem. Even plants and animals on land would have struggled as the climate became more arid and resources scarcer.
The Impact on Climate
The disappearance of the Mediterranean Sea would have had far-reaching consequences on the climate.
Without the sea, temperatures around the Mediterranean would have become more extreme, with scorching summers and freezing winters. Rainfall patterns would have shifted, leading to droughts in some areas and floods in others.
But What Did it Look Like?
Geographically, the landscape would have been transformed. Rivers that once flowed into the Mediterranean, such as the Nile and the Rhône, would have carved deep canyons into the exposed seabed.
The Nile, in particular, is believed to have extended its course by several hundred kilometers, creating a vast canyon comparable in size to the Grand Canyon.
The Return of the Sea
The Messinian Salinity Crisis came to a dramatic end about 5.3 million years ago when the Atlantic waters broke through the Strait of Gibraltar, initiating what is known as the Zanclean Flood.
In a matter of months or even weeks, the Mediterranean basin was refilled in one of the most catastrophic floods in Earth’s history.
What Caused the Flood?
Over time, the Strait of Gibraltar slowly eroded and opened again. There’s some debate as to whether rising sea levels or tectonic plate shifting played a part.
With the strait reopened the Atlantic Ocean was able to flow through the Mediterranean Sea again. Goodbye, depressing desert, and hello, crystal blue waters!
The Zanclean Flood
Imagine a wall of water hundreds of meters high crashing down into the dry basin, refilling it at a rate that would have made the largest waterfalls on Earth today seem small. Within just a few months, the Mediterranean Sea was back to its normal water levels.
The rushing waters restored the Mediterranean Sea and reshaped its ecosystems, making it the stunning region we know today.
Local Legends
Before we had scientific evidence to explain the Earth’s changes, we had folklore. One story often told in Southern Spain and Portugal is that the Greek hero Hercules was responsible for bringing water back to the Mediterranean.
The story goes that he dug a waterway between Spain and Morocco with just a sword. To tell the truth, a hero swooping in to save the day is definitely a more exciting explanation than erosion.
Could This Happen Again?
While the idea of the Mediterranean Sea disappearing again might seem far-fetched, it’s not entirely impossible. The world is constantly changing, but large-scale changes like this would likely happen over thousands of years.
It wouldn’t happen suddenly, and no one alive today would see it, but perhaps in another 5.5 million years…
