字幕表 動画を再生する
Tsunamis are some of the most
powerful and deadliest forces of nature.
Within recent memory, you may recall both the 2004 Indian Ocean Tsunami and the
2011 Japan Tsunami, both of
which in resulted catastrophic damage
and loss of life.
The Indian Ocean Tsunami
happened after a massive earthquake
struck here in the Indian Ocean.
The earthquake itself released more energy than every single explosive detonated in the entire Second World War, including the nuclear bombs.
This enormous amount of energy created a tsunami that reached heights of 30
meters high in some places, or about the
height of 17 people stacked on top of
each other.
The wave smashed into Indonesia, South
Asia, and the east coast of Africa,
punching as deep as two kilometers
inland from the coast in some places.
As you can see from photos like this one,
the damage in these places was often extensive.
The tragedy claimed the lives
of around 250 thousand people, making it the
deadliest tsunami in all of history,
while the 2011 Japan Tsunami was the
costliest in terms of damage.
That tsunami was also generated by an
earthquake that created waves as high as
40.5 meters; just about five
meters shorter than the Statue of
Liberty, that came slamming into the
Japanese east coast traveling up to ten
kilometers inland away from the coast.
As you can see from photos like this that
look like something straight out of a
Hollywood blockbuster, with what used to
be a road stretching out into the
endless ocean, the economic cost of Japan
was enormous: an estimated 300 billion
dollars in damages was done, more than
the entire GDP of South Africa. But these
are what are called "regular" tsunamis and
there is an entire other class of
gigantic waves that are simply called
"megatsunamis".
Unlike a regular tsunami that is created by an earthquake, a megatsunami
is usually created when a
massive amount of material suddenly
falls into water, which displaces that
water into a huge wave.
The most tragic and possibly terrifying instance of this
happening in recent times was back in
1963, here in Italy, just
100 kilometers north of Venice.
The Italian government and a construction
company were building what at the time
was going to be the largest dam on Earth;
the only problem was that they were
building this dam with a huge water
reservoir the size of a large lake, right
next to one of the most unstable
mountains on the planet.
For months leading up to the completion of the
dam, there were several minor landslides and other signs
that there could be a catastrophe coming,
but rather than heed the numerous warning
signs, the Italian government actually
decided to sue the few journalists
reporting on the issue for quote:
"...undermining the social order".
The government and company continued to
ignore all the warning signs until it
was obvious that the mountain was
actually going to collapse directly into
the dam's reservoir.
Tthe engineers calculated the landslide that would
likely occur, lowered the water in the
reservoir to what they believed was a
safe level, and then actually stood on
top of the dam the night that they expected the
landslide to occur to watch it all go down.
The only problem was, the landslide ended up being over 10 times more powerful
than what their calculations had predicted!
This is a view of that mountain today:
this right here used to be the reservoir, and all the land that's
there now came crashing off the mountain
from these areas that are now exposed white rock.
This tremendous amount of earth and rocks fell into the reservoir
in a matter of seconds, completely filled
the entire reservoir and generated a
wave 250 meters high that flew over the
top of the dam, and into the villages below.
The wave was almost the same
height as the TransAmerica building in
San Francisco for some reference, and
caused an impact crater 60 meters deep
and 80 meters wide when it slammed into
the ground on the other side of the dam!
If you were standing from this angle looking up at the dam at the exact
moment that the wave came over it,
the entire sky that you see in this picture
would be completely covered by water!
This photo was taken in the town of
Longarone, which before the megatsunami looked like this,
but afterwards looked like this: completely destroyed.
Around 2,000 people lost their lives in
the accident, but it's not actually the
largest mega tsunami even in recent history.
That distinction would have to go to a megatsunami that happened here
in Lituya Bay, Alaska, back in 1958.
A powerful earthquake caused a massive
landslide to occur here at the back side of the bay.
The huge amount of land
that came crashing into the bay created
a titanic wave 525 meters high that
slammed into this part of the bay,
completely went over it, and smashed into
the other side here, causing huge amounts
of damage to the rest of the bay and
destroying millions of trees.
The height of this wave was over 100 meters higher
than the tip of the Empire State
Building, and just 16
meters short of the recently built
One World Trade Center in New York City, but
even this is tiny in comparison to some
prehistoric megatsunamis. The largest
tsunami generated from a landslide
happened around 1.5 million years ago in
Hawaii.,on the specific island of Molokai.
At some point around that time, about
one-third of the northern portion of the
volcano collapsed into the ocean and
generated a wave 600 meters high, which
would have completely inundated the
entire island of Molokai and wreaked havoc
on the rest of the island chain. This
wave would have been about the height of
four Great Pyramids of Giza stacked on
top of each other... but even that pales in
comparison to the largest ever known
megatsunami, which was caused by an
asteroid. About 66 million years ago, the
same asteroid that likely killed the
dinosaurs also caused possibly the
largest megatsunami in all of Earth's
history when it crashed into the
modern-day Gulf of Mexico. The asteroid
was ten kilometers in diameter and
released an unbelievable 100 TERATONS
of TNT worth of energy. For comparison,
the Tsar Bomba (which is the largest
nuclear bomb ever detonated), released
only 1/2,000,000th of that same amount of
energy. You would need 2 million Tsar
Bombs to release this same amount of
energy, which caused an equally
unbelievable wave of up to 5
KILOMETERS high that would have smashed
into the Gulf Coast states of the
modern-day United States. That's higher
than the Matterhorn in the Alps... by about
500 EXTRA METERS. In fact the height is
higher than all of the mountains in the entire Alpine Mountain Range.
These waves were so big that if they
were to have happened in the Indian Ocean, the entire island of Madagascar would have been
completely submerged underwater for a
time. Imagine being on an island the size
of Madagascar in this scenario, with
absolutely no escape from the clutches
of the ocean's waves no matter how high
on the land that you can get to! It's a
weird thought, but at least it happened
66 million years ago and there's really
no fear something like that ever happening
again, right? Unless the 0.00001 percent
chance of one of the Canary Islands
collapsing into the ocean during your
lifetime happens, which would cause a
tsunami about 1 kilometer high and
would probably wipe out the entire East
Coast of the United States... unless that
happens then no, probably not. But, it's
still fun to think about.
This video has been brought to you by "audible.com", with
over 180,000 audiobooks and almost every
genre you can imagine. You can get a free
30-day trial today by going to
audible.com/RealLifeLore. You can
get a completely free audiobook of your
choice, and if you liked the video that
you just watched, then why not read a
little more about how insane tsunamis
can get by picking up a copy of "Krakatoa:
The Day the World Exploded".
I didn't have enough time to cover every
tsunami related story in this short
video, so give it a listen with your free
30-day trial by going to audible.com/RealLifeLore.
Audible has a near endless library of
interesting things to listen to so if
you'd rather listen to something else
for free with this, then that's completely fine, too.
Thanks to Audible for supporting the channel.
And if you'd like to watch another video about natural disasters,
you can go check out this video by Second Thought here on YouTube.
You can subscribe to my channel by clicking here,
and you can visit my Patreon by clicking here.
Thanks so much for watching, and we'll see you next time.