Original subtitles

[William Shatner] A dense forest,

leveled without explanation.

Ravenous insects on a path of total destruction.

And a massive tremor

that may have been caused by human hands.

Fire.

Floods. Earthquakes.

Humanity has always faced

natural disasters that often strike without warning,

leaving death and destruction in their wake.

But there are many other strange

and rare events that are just as frightening

and deadly.

Like mysterious fireballs that race through the sky,

exploding toxic lakes

and powerful tsunamis that some believe

can summon the dead.

Are these disasters simply freak events?

Or could they be signs of something unnatural at work?

Well, that is what we'll try and find out.

♪ ♪

[Shatner reads on-screen text]

At over two million square miles,

it's the largest forest on Earth.

And on June 30, 1908,

this remote and inhospitable landscape

experienced a devastating disaster

known as the Tunguska event.

On this June morning in 1908, a massive explosion

occurs over this remote part of Siberia.

This became a major mystery in world history.

At this period in time, this area was mostly inhabited

by an Indigenous group called the Evenki.

They had traditionally engaged in reindeer herding,

and there were several of them who were out

pretty close to the epicenter of the blast.

Evenki herders see a bright object in the sky,

described as brighter than the Sun.

[loud booming]

And then, they heard these loud booms,

louder than gunshots.

[Ben McGee] What the Evenki described was nightmarish.

Suddenly, another sun appears in the sky.

[loud booming]

You hear the loudest noise you've ever heard

along with a very violent shockwave.

People were blasted off their feet

and thrown a distance.

And then, almost as fast as it started,

this fades away, and

you're left wondering, what happened?

[Tony McMahon] There is an enormous explosion,

and what happens is that something like

80 million trees are flattened

over an 800-square-mile area.

I mean, this is absolutely bizarre,

and yet, here you have this devastation.

[Paul Byrne] It must've been terrifying.

Every single tree is flattened in the same direction.

80 million of them over 800 square miles.

We just see flattened trees

completely scorched and devoid of any branches or leaves.

[Shatner] What kind of explosive force

had the power to annihilate

an 800-square-mile area?

It's been estimated this would require

the energy equivalent of 1,000 atomic bombs.

Early 20th century theories proposed the disaster

was the work of a massive meteor

striking the Siberian wilderness.

[Bruno] When the Tunguska blast occurred in 1908,

and even when it was first investigated in the late 1920s,

the expectation was

that this must be one of the largest

meteorite events in modern times.

One of the early researchers was this guy, Leonid Kulik,

who gets support from the Soviet Academy of Sciences

to begin these expeditions.

In 1928, Leonid Kulik expected to find

a crater and a big chunk of metal.

But he did not find a crater or a meteorite.

Even to this day, we have not found

a crater that was caused by Tunguska or even material

that can clearly be traced back to a cosmic origin in 1908.

[Byrne] How did something smashing into Earth

leave no crater and flatten 80 million trees

without leaving any other trace of it?

When an asteroid or comet smacks into Earth's surface,

the classic thing that you get is an impact crater.

Meteor Crater in Arizona is a perfect example of this.

But in the Tunguska event,

we see no evidence of a crater at all.

And so, the enigma here is,

how do you get, potentially, something striking Earth, but

not seemingly to strike Earth at all?

[Shatner] In the absence of an impact crater

or verified cosmic debris,

attempts to explain the unnatural event

have ranged from a black hole passing through Earth

to weapons of mass destruction.

But 70 years after Tunguska,

a strange anomaly on a small island in Newfoundland, Canada

may offer some clues to the cause

of the mysterious Siberian disaster.

It's known as the Bell Island Boom.

April 2, 1978, in Newfoundland,

about 5,000 residents of Bell Island

suddenly, spontaneously, see an enormous flash of light,

and it's followed by an explosion

that damages almost every building in the town.

Gouts of blue fire erupt from power outlets.

Livestock were killed,

and the sound of this blast was heard 80, 90 miles away.

And initially, they thought, well,

maybe this was a giant meteor impact, but

there was no crater, there was no impact debris.

So, people thought immediately of similarities with Tunguska.

One possible explanation for the Bell Island Boom

is what we call a superbolt.

We think that superbolts are basically lightning bolts,

but they're far, far more powerful than a normal one.

They release trillions of watts of energy instantaneously.

So, that leads scientists to wonder,

could a superbolt be responsible for this Bell Island Boom?

[Shatner] Was an extremely rare and powerful lightning strike

the cause of both the Bell Island Boom

and perhaps the Tunguska event?

While it's a matter of speculation,

many scientists believe the real answer came even more recently,

and much closer to where the Tunguska event took place.

[Shatner reads on-screen text]

This major industrial center

near the border of the Siberian taiga

is one of the largest cities in Russia.

On February 15, 2013, at approximately 9:20 a.m.,

residents record incredible footage

of a meteor the size of a house

rocketing through the sky.

Sometimes, an asteroid or a comet can come in

at a very shallow angle,

parallel with the surface of the Earth

to blow up in the atmosphere,

and it's there where you can get something we call an airburst.

In 2013, there was just such an airburst.

It was about 14 or 15 miles up.

It came in, heated up, turned into a fireball

brighter than the Sun, and left

a huge cloud through the atmosphere.

[man speaks Russian]

[McGee] And people filed outside

to see what the bright light was caused by.

And little did they know, that whole time, through the air

was an invisible shock wave carrying the sound

and the force of that blast, half a megaton.

And boom!

Every window in the town is shattered.

Every car alarm goes off at the same time.

Thousands of buildings were damaged,

thousands of people injured.

And this was a small-scale Tunguska that we got on video.

[Byrne] We now think that the most likely explanation

for the Tunguska event is that an object

hit Earth's atmosphere at extremely high velocity

and exploded, and that energy release was enough

to flatten those trees, scorch the ones nearby.

And rather than excavating a crater,

it basically just blasts out a wave of energy

that flattens trees.

And it may be that the Chelyabinsk event

explains all of the eyewitness testimony

of people back in 1908 reporting what they saw.

It's our best explanation right now,

but we may never know for sure

what caused the blast in 1908.

[Shatner reads on-screen text]

This dry and arid region encompassing Kenya,

Ethiopia, and Somalia

is famous for its dramatic mountains

and vast savannas.

But in 2019, it became ground zero

for a locust swarm of unimaginable proportions.

[Jeffrey Lockwood] The most famed or infamous locust

is the desert locust of Africa.

Where they land, it's utter devastation.

They are descending in order to feed,

and you can watch your fields disappear before your eyes.

So, to understand locust swarm,

you have to kind of go back a few,

a few months or a few years.

The parents of these locusts

would've appeared as garden-variety grasshoppers.

But then, the conditions change.

It becomes drier, and they undergo

a Dr. Jekyll to Mr. Hyde transmogrification.

And instead of their offspring looking like their parents,

they're like mobs of small, wingless, uh, locusts

that march across the land just eating whatever they encounter.

And then, after about three weeks,

they molt into adults, winged adults.

And they rise into the sky, and they

appear to be kind of a glittering storm cloud

on the horizon.

And if you're a farmer, you watch

your crops melt in front of you

so it looks like a wildfire has swept through.

Nothing is gonna stop them until they're done.

They leave nothing behind except misery and hunger.

[Shatner] The East African locust swarm of 2019

destroyed an estimated $8.5 billion dollars' worth of crops,

resulting in a food crisis

affecting nearly 25 million people.

But history's most devastating and mysterious swarm of locusts

assembled nearly 150 years before the African disaster.

This time, in the United States.

[Shatner reads on-screen text]

From the Rocky Mountains to the Mississippi River,

American farmers struggle to survive.

Years of harsh weather conditions and drought

creates hard, dry prairie soil difficult to farm.

But even more devastating is the freakish mega swarm of

Rocky Mountain locusts that have assembled

on a biblical scale.

[McGee] This wasn't just any locust swarm.

There were more than 12 trillion locusts that made a swath

that was a thousand miles long,

and basically, you can think of

a swarm the size of California

munching its way across the American Midwest.

And these locusts were so ravenous,

they not only absolutely annihilated

all the crops in the American Midwest,

the locusts began eating

anything else they could find that was organic.

That includes the wool off of live sheep,

it includes wood structural elements of houses,

and it includes clothing that people were wearing.

And so, this was terrifying.

These things were alive and they were hungry.

[Lockwood] This mega swarm of 1875

is the largest recorded swarm in human history.

It was 2,000 times larger than the next largest known swarm

of locusts on planet Earth.

Something that summer coalesced them into this mega swarm.

It was a natural disaster of unimaginable scale.

500 to a thousand tons of vegetation

have to be consumed every day to fuel that swarm.

Much of the Midwest was gonna face hunger.

People are gonna die.

But we don't really know very much about what led up to it.

[Shatner] Over the course of three years,

the ravenous insects devoured $116 billion dollars' worth

of crops and property,

leading to widespread starvation

and complete financial ruin for countless families.

And based on this unfathomable devastation, many wondered

was this mysterious disaster a grim judgement

from the Almighty?

[McMahon] If you read the newspapers from the time,

it really conveys the terror

that these farming communities felt

as these locusts completely destroyed their livelihoods.

And of course, many of these God-fearing people

looked to the Bible and thought, "Well,

Pharaoh in Egypt was punished with locusts.

Surely, we're being punished for our sinfulness.

We have done something wrong

and we are now facing divine retribution."

That's what many people thought.

[Lockwood] Governors in five western states

declared days of prayer.

And then, you say, "Well,

God helps those who help themselves."

What do you do in the industrial age to fight nature?

Build a machine. Right?

Machinery must be the answer.

All kinds of machines are built.

One was called the King Suction Machine.

A belt-driven, gigantic vacuum that would suck up

the nymphs-- these are the wingless immatures--

and bag them.

[horse neighs]

You might try various rolling devices to crush these locusts.

One of my favorites was, basically,

a flamethrower to torch the locusts.

Not very effective, but it probably felt pretty good.

Now, did it make a dent in the locusts, probably not,

but it did give the people a sense of being in control.

[Shatner] While we still don't know what caused the largest,

most destructive locust swarm in history,

what's even more perplexing

is that, by the year 1902, just 27 years later,

the Rocky Mountain locust completely vanished

from the face of the Earth.

[McGee] It was only a couple of decades after

this titanic storm

of locusts that the Rocky Mountain locusts

went extinct, disappeared forever.

You talk about a dynamic contrast.

It went from effectively swallowing the country...

...to vanishing without a trace.

And why?

Well, perhaps it was loss of habitat

and human civilization's advance just meant the conditions

weren't favorable for them anymore.

We don't really know.

[Lockwood] Another theory was

they didn't go anywhere, they're still here.

And it just so happens that the right conditions

have not happened again

that would transform an existing grasshopper

into the Rocky Mountain locust.

We still can't explain what caused the rise

of the Rocky Mountain locust swarm

and ultimately what caused their demise.

And it may forever remain a mystery.

♪ ♪

It's baffling to think that trillions of locusts,

swarming over an area more than a thousand miles wide,

could suddenly vanish into extinction.

[clicks tongue]

But that's not the only mystery of nature

that continues to defy scientific understanding.

For example, there's a lake in Cameroon

that may be part of a network of toxic, ticking time bombs.

[Shatner reads on-screen text]

The Sun rises over the hills surrounding

an ancient body of water known as Lake Nyos

and reveals an apocalyptic scene.

In nearby villages, lifeless bodies are strewn about

as if a mysterious force had swept across the land

killing nearly everything in its path.

There was a terrifying

geological catastrophe that occurred.

Something disrupted this lake.

Locals reported a rumbling sound and what might be described

as an explosion as the lake suddenly came to life.

And anyone who was caught in its path

instantly dropped dead.

[Shatner] The death toll was staggering.

It's estimated around 1,700 people and 3,500 animals

were killed across a 14-mile radius.

With no obvious cause of death,

an international team of scientists--

including American biologist George Kling--

was dispatched to investigate.

We really didn't know what had happened, what had caused this.

And the lake itself was

very reddish-orange,

like a rust color

that we really don't see very often in lakes.

And there was a lot of damage around the shoreline

from some large wave

that must have been produced with enough force

to wash away all the vegetation and soil down to bare rock.

And lakes just don't explode like that.

[Shatner] What exploded out of Lake Nyos

killing everything in its path?

Given that the lake was formed in an ancient volcanic crater,

investigators feared that an eruption,

deep underground, released a surge of deadly gas.

[Kling] Many of the survivors reported smelling rotten eggs

or gunpowder, and that's an unmistakable smell of sulfur,

and they reported feeling warm.

And we know volcanoes produce a lot of sulfur gas

and a lot of heat.

But when we started analyzing our samples,

we found no sulfur in the lake water.

We found no excess sulfur in the plants

around the lake that had been exposed to this gas cloud.

And when the army pathologists did autopsies,

they found no evidence

that people were poisoned by sulfur gas.

[Shatner] No poisoning by sulfur gas?

Experts were left wondering

if the cause of this deadly disaster

was even geological at all.

Local rumors swirled about chemical spills,

weapon tests,

even stories about vengeful spirits in the lake.

But George Kling found something intriguing

buried in old medical reports.

A clue pointing to a rather unlikely culprit,

a gas that we all produce when we exhale,

carbon dioxide, otherwise known as CO2.

[Kling] We ran across some older medical literature

that had used high concentrations of CO2

to test for oxygen stress in fighter pilots.

And it turns out that CO2

above concentrations of about six percent

acts as a sensory hallucinogen.

And one of the most common reports from the fighter pilots

was that they smelled rotten eggs and gunpowder

and that they felt very warm.

So, we knew that this was a CO2 release,

and we suspected that the gas was held in the lake.

It turns out that the lake itself

could hold a huge amount of gas in the bottom waters.

[Shatner] Kling's tests reveal

that Lake Nyos was primed for disaster.

Over centuries, the lake had become a pressurized

chamber of carbon dioxide.

And when that chamber exploded,

it released a massive wave of suffocating gas

that raced across the land at over 60 miles per hour.

Lake Nyos, as it turns out,

was supercharged in carbon dioxide,

much like a soda can

if you shook it up before you opened it.

So, anyone unfortunate to be caught in its path

couldn't breathe.

[Kling] One of the things that made this event so deadly

was that this CO2 gas cloud was enormous, first off,

but because it was heavier than air,

it flowed out of the lake and down the river valleys

very quickly, so even if people had seen

the cloud coming, they couldn't have gotten out of the way.

And people just essentially died in place.

Lake Nyos was vulnerable to this kind of an event because

it was formed by volcanic activity,

and it's also very deep.

So, those deep waters could store a lot of gas.

But once we have the gas build up, we have to have a trigger,

and this could be any number of things.

For example, it could be a landslide

that caused the gas burst,

but we'll probably never know for sure

what triggered this disaster.

[Shatner] Based on Kling's discovery,

Lake Nyos is now monitored around the clock

to help anticipate another deadly gas event.

But solving the Lake Nyos disaster reveals

a far more terrifying question.

With more lakes potentially primed

for the same kind of catastrophe,

when and where could this happen again?

Lake Kivu in East Africa is the nasty big brother of Lake Nyos.

It's 1,600 times larger.

It has a thousand times more gas in it.

And because there are millions of people

living around the shoreline of that lake,

it's the largest ticking time bomb in the world.

There are active volcanoes in the area.

And these volcanoes could destabilize it

and trigger a gas burst.

We haven't looked at every single lake in the world,

but we know now enough about what

kinds of lakes could be dangerous.

[McGee] Knowing that this is a process

that the Earth can throw at us,

it's natural to wonder, are other lakes susceptible?

The good news is it doesn't happen everywhere.

But the bad news is, if there's one that we don't know about,

we need to find it first before it lets us know

it's there in all the worst ways.

How many lakes around the world are filled with poisonous gases

that could explode at any minute?

While there's much left to learn,

there are some disasters

that aren't triggered by natural processes

that take millions of years to unleash.

Like in the case of a catastrophic earthquake

that may have been the result

of human engineering.

[Shatner] Throughout history, Mother Nature has revealed

that the ground beneath our feet

is far less stable than we like to imagine.

In the last century alone,

cities have been suddenly reduced to rubble.

And nearly two million people around the world

have been killed by the unbelievable ruin

caused by earthquakes.

[Klose] Earthquakes we can observe around the world.

Wherever you are on any continent,

you have plenty of fault zones everywhere.

Large fault zones will cause large earthquakes,

and an earthquake happens if you build up stress

over thousands and millions of years,

and those fault zones can basically rupture at some point.

[Shatner] While scientists can't predict

when an earthquake will strike,

we generally assume that they're caused

by natural processes that take an extraordinarily long time.

But could some of the deadliest earthquakes of the modern age

be caused by human hands?

[Shatner reads on-screen text]

This region is home to over 80 million people,

making it one of the most populous places in all of China.

But just before 2:30 in the afternoon,

a massive earthquake unleashes

unspeakable death and destruction.

[Shatner] The deadly earthquake struck along

a 155-mile fault line

running the base of the Longmen Mountains.

But when scientists pinpointed the quake's epicenter,

they found something massive and man-made.

The question is, what triggered that earthquake?

Although we know that this region

is a natural seismic region

where we have earthquakes every other hundreds of years,

seismologists are able to measure

how waves propagate through the Earth's crust.

And that's what they did.

They looked at the seismic wave they recorded

and they could see that, in the first ten to 15 seconds,

most of the energy was released

right in the vicinity of the Zipingpu Dam.

[Shatner] The Zipingpu Dam stands over 500 feet tall,

and its reservoir holds

more than 296 billion gallons of water,

weighing more than one trillion tons.

Scientists began to wonder,

did this monumental engineering project somehow

trigger the earthquake

that killed an estimated 87,000 people?

When it comes to the idea of humans

artificially triggering earthquakes to occur,

if you do something to add a lot of weight to an area--

like create a dam and then generate a new lake--

well, the weight of all of that water

can induce any number of changes.

And in some areas, definitely activate earthquakes.

That's what led us to suggest

that the pressure can be that large

and that could weaken the fault and trigger the earthquake.

[Shatner] While it seems the Zipingpu reservoir

could have a role in the deadly Sichuan earthquake,

the theory remains controversial

and is not acknowledged by the Chinese government.

But it all raises a chilling question.

What other massive man-made structures could potentially

bring about an unnatural disaster?

[Byrne] Closer to home, the Hoover Dam is among

the largest reservoirs in the world.

[explosions]

And in fact, even during its construction in the 1930s,

there were quakes nearby because there are structures

in the ground that are going to move.

The big question becomes this, if those structures move again,

are we going to have an issue with this dam?

There's no doubt that

whether it's caused by man or Mother Nature,

those impacted by a disaster are left

haunted by the event itself

and the aftermath that follows.

But when the tsunami of 2011

destroyed parts of Japan, some locals were affected

on an otherworldly level,

when the living were reportedly visited

by the dead.

[Shatner reads on-screen text]

A massive 9.1 magnitude earthquake

strikes dangerously close to the Japanese mainland.

This seismic event displaces so much water,

it sends hundred-foot waves

barreling towards Japan's eastern shore

at 500 miles per hour,

in an event known as the Tohoku earthquake and tsunami.

[Parry] The earthquake set off a massive tsunami,

which struck the coastline of Eastern Japan,

and that is what caused devastating damage.

It's like the tide coming in

unstoppably, massively, and very, very, very fast.

The tsunami smashed into villages, towns, ports

all along the coast.

It caused a meltdown

at the Fukushima Daiichi nuclear power station,

which turned into the second worst

nuclear disaster in history.

The devastation is overwhelming.

Imagine turning all houses, factories sideways,

spreading out all the chemicals and debris,

destroying roads.

You have flows that are filled, not just with mud and trees,

but cars, and building fragments and rooftops.

And this is spread all the way inland, many miles,

and then dragged back out to sea.

There were more than 19,000 people killed

in this event, and it becomes

the deadliest event in Japan's history since World War II.

[Shatner] The entire region grappled with enormous loss

and unimaginable trauma.

And some who managed to escape death

would also experience disturbing events

of an otherworldly kind.

Because in the months after the tragedy,

tsunami survivors started to report

ghostly encounters with the dead.

[Parry] Six months or so after the tsunami,

among many people who survived it,

you did begin to hear

various stories about

supernatural mysterious events.

There were stories about

mysterious figures glimpsed by the coast on the beach.

And then, there were

also the stories told by-by taxi drivers.

A taxi driver is flagged down by a lonely figure

who got in the back of the taxi

and gave him an address.

And he gets there

and, sure enough, there is nothing there.

All the houses have been smashed to pieces by the wave.

He looks in the back of the taxi--

the person isn't there.

And he understands that

the passenger was a ghost who wanted to go back

to the place where they'd formerly lived.

There was something ghostly

happening along that stricken coast.

[Shatner] Did thousands of sudden deaths unleash

the spirits of those that perished in the tsunami?

It's an unnerving question

because there were also reports that these spirits

possessed the living.

[speaking Japanese]

[translated] I perform purification rituals,

but also exorcism, if you will.

Living people were possessed by spirits.

After the tsunami, everyone around there

had almost no physical or mental immunity left.

So, they were in a state where spirits

could easily attach themselves.

So, our method of exorcism

involved guiding them into a meditative state

and then expelling it with a big breath.

Strangely enough, with one woman,

smoke suddenly puffed out of her mouth and the spirit left her.

And when she came back to normal,

she was like, "Why am I here?

Did something happen to me?"

[Shatner] While the actual number

of claimed spirit possessions is unknown,

mediums, folk healers, and holy men

became inundated with desperate calls for help.

[speaking Japanese]

[translated] I was in the thick of it,

facing people suffering from possession

and doing whatever I could.

They're in a daze. Their face is blank. They're limp.

It feels like their personality has changed.

We performed rites to calm them.

You need the power of ritual and the power of deep listening.

I engaged with them and released them from possession,

and brought them back to daily life.

But facing possession takes so much out of you,

to the point you feel you might die.

[Shatner] Did tsunami ghosts roam Japan's devastated coast

and possess those that survived?

While some are convinced that this was a real

supernatural phenomenon,

others suggest a less esoteric explanation.

After a terrible disaster like this,

I think there are two impulses that people have.

One is naturally to feel

horror about what has happened,

and I think these stories of ghosts,

the sense of the supernatural bearing in on all sides,

is an aspect of that, of that fear and that horror.

But there was another side to it.

There's a strong, strong yearning

to connect with the dead.

To say the goodbyes, the farewells

that weren't possible in this sudden catastrophe.

But to the people having the experiences,

they were very, very real,

and they needed to be taken seriously.

[Shatner] Natural disasters have always threatened humanity.

Some believe the danger's only growing.

Between the year 2000 and 2019,

there were over 7,000 major recorded disaster events

around the world,

nearly twice as many than the previous two decades.

And scientists warn that the next major disaster

could come from immense forces

buried beneath the Earth's crust.

[loud booming]

[Byrne] One source of catastrophic

environmental change we know happened in Earth history

are gigantic volcanic eruptions.

If we look through the geological record,

we see thousands of these events.

Like we saw in Siberia about 250 million years ago

leading to the biggest mass extinction in Earth history.

98% of all species on Earth went extinct.

The atmosphere was rendered almost unbreathable

because of how much CO2 came out.

We know that these kinds of events have happened

through Earth history.

In fact, geologically, they happen regularly,

and we do not have the ability

to predict if or when the next one will happen.

There are catastrophic eruptions that volcanoes are capable of,

and Yellowstone is a great example.

Yellowstone Caldera is a huge depression in the ground

with an enormous body of magma at depth.

Now, right now, that magma seems to be relatively stable,

but we know that there were gigantic volcanic eruptions

in the past, and it may yet explode in the future.

[Shatner] Could a massive volcanic eruption

unleash Earth's next mass extinction event?

It has happened before.

But there are other apocalyptic forces not born of this Earth,

like the same cosmic threat

believed to have killed the dinosaurs.

A lot of extinctions in our past were actually caused by comets.

If you were to look at our solar system,

the whole solar system is surrounded

by a giant sphere of old junk.

Think of it as icy spare parts

from when the solar system was first built.

This is where all comets come from.

And one hypothesis is that,

as our solar system moves through the galaxy-- bam.

A slew of comets are fired in toward the inner solar system,

and so it really does make you wonder

whether future mass extinctions

have to do with our galactic neighborhood.

[Shatner] Will a series of comets

soon bombard Earth like artillery shells?

The fact is, we can't accurately predict future disasters at all.

And mankind lives and dies

at the mercy of forces that are beyond our control.

[Byrne] At some point in the future,

it won't be a question of if, but when

Earth decides to clean house.

But every time these disasters happen,

the environment bounces back.

Now, I hope we won't learn this on our own lifetimes,

but it will surely happen again at some point.

One question we should ask is, have we figured out all the ways

in which these disasters might happen?

[Kling] Most of us understand that being prepared

doesn't always help us when we're exposed to the unknown.

We have to accumulate more facts,

more information.

Sometimes, people assume that

scientists have it all figured out,

that they have seen everything.

They pretty much understand what's happening.

But these disasters have really shown us

that we had no idea about major events

that have happened in the past

and may happen in the future as well.

Is Earth overdue for an unspeakable disaster

on a scale we've never witnessed before?

Well, I sure hope not.

And whether a massive volcano erupts,

a giant space rock collides with Earth,

or any number of terrible cataclysms are on the horizon,

it's clear that deadly catastrophes are inevitable

as long as we call this planet our home.

While Mother Nature has taught us to respect the elements,

it's the unpredictable

and unnatural disasters that leave us humbled

by forces that remain unexplained.

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