There are over one million volcanoes
on our ocean floor.
And all of them suddenly started
spewing out red-hot molten rock.
The ocean is filling with lava.
And nothing can prepare you
for the devastation to come.
Many volcanos sit atop
shifting tectonic plates,
building pressure over years
before they're ready to blow.
Scientists estimate that four out of five
volcanic eruptions happen underwater.
But for this to be truly apocalyptic,
we'd need to wake up volcanoes
that have been dormant for over 10,000 years.
You'd see the most activity
in the mid-Atlantic as these waking giants
rip the planet apart.
But underwater volcanoes don't really erupt in epic explosions.
Instead, they scatter lava across the ocean floor,
rocking the submarine landscape.
As more than one million underwater volcanoes spew out lava in the water,
that water would become acidic.
All thanks to the devasting amount
of carbon dioxide coming from eruptions.
Sea organisms would die off quickly
in this harsh environment.
And this is where the food chain would break.
But how would this affect life above water?
The lava would build and build,
creating new landmasses that would tower over the waves.
We might see islands pop out of the oceans everywhere.
Experts think that this is the process
that gave us Iceland 70 million years ago.
But if the magma didn't keep flowing,
these newly formed islands could be slowly
lost to erosion from the wind and waves.
Anything that withstands this constant erosion
would be covered in ash.
Usually, each of these islands
hosts a variety of life.
Islands play a vital role
as natural resting places and breeding grounds for migratory birds.
And new microscopic life
could thrive in the volcanic soil.
But if every underwater volcano
was constantly erupting non-stop,
all that ash would stop both birds
and organisms from finding a home in these areas.
And the devastation wouldn't end there.
The poisonous compounds
would be spread across entire regions and over continents.
In 2009,
an eruption in the Tonga archipelago
rocketed ash to an island over 63 km (39 mi) away.
Even worse,
with the pressure released from all these volcanos erupting,
tsunamis could rise
and devastate coastlines.
Hunga Tonga-Hunga Ha'apai burned so hot
following its 2021 eruption that it blazed a crater into the ocean floor.
It also triggered a tsunami
that flooded the islands of Tonga
in minutes with over 18 m (60 ft) of water.
Every nation surrounded by water
would face the same risk during these violent global eruptions.
Maybe you'd be safer inland?
Right?
Meanwhile,
underwater landslides could also destroy ocean life.
All the rock and ash being sprayed out
would change the face of the ocean floor.
And the boiling waters would cook marine life,
and their charred remains
would float to the surface
as an ominous sign of the dangers below.
Landslides would also destroy island
populations around volcanic chains.
If the ancient submarine volcano known as Marsili,
located in the Mediterranean,
collapsed during the eruption,
it could be disastrous.
The tsunami generated could flood
the coastlines of Italy.
That's just one volcano.
And all that tectonic energy released
would mean even more earthquakes
and tsunamis worldwide.
No matter where you live,
you may not be safe in this new world.
Each continent could be destroyed
from below as the plates shift during the eruptions.
Cities far inland could feel the effects
as mountain ranges bulldoze entire regions
and deserts are flooded.
But what if you traveled to an even more dangerous planet?
Keep watching,
because that's a story for another WHAT IF.