.
You're fishing in a lake,
on a nice sunny day.
When suddenly, you begin to smell rotten eggs.
And before you know it,
the lake explodes.
Your boat starts rocking violently,
and you begin to feel dizzy.
In the distance,
you see a 20 m (65 ft) high wave
coming towards you.
Now you'd better get out of there
before it's too late.
A limnic eruption
is an incredibly rare and dangerous
natural disaster.
It happens when a lake
sits near a pool of magma.
Since the magma gives off carbon dioxide,
it builds up underground over time.
Eventually, the CO2 bubble bursts,
creating a massive explosion in the lake.
When this happens,
carbon dioxide gases spread everywhere,
and tsunami-like waves pop up out of nowhere.
Luckily, this has only happened a couple of times.
But when it does,
the results are devastating.
In Cameroon,
a limnic eruption occurred in 1986,
killing 2,000 people
and wiping out entire communities.
If you were near a lake during a limnic eruption,
how would you survive?
Before the lake erupts,
pay attention to your nose.
If you smell rotten eggs,
that means an eruption could happen soon.
Also, check to see if the water
is warmer than usual.
That's another sign of an imminent eruption.
As this is happening,
move away from the lake as quickly as possible.
This will help you to survive the initial blast.
When the limnic eruption occurs,
hold your breath immediately.
The magma chambers underneath this lake
are erupting millions
of cubic meters of carbon dioxide.
Carbon dioxide can be fine
at low concentrations,
but high concentrations
greater than 10%
will occur from the eruption.
If you start breathing it in,
you'll quickly pass out, and die.
So hold your breath for as long as you can.
Now that you've survived the initial blast,
it's time to get out of there.
Don't run away on foot.
Instead, get in a car and drive away.
You'll want to move fast,
as both the water and carbon dioxide
will cover some serious ground.
Anyone in a 25 km (15 mi) radius
of the eruption will either get
hit by the tsunami-like wave,
or suffocate from the carbon dioxide.
When you begin to drive,
immediately move towards higher ground.
This is the quickest and safest way
to avoid the aftermath of the eruption.
Since carbon dioxide
is denser than air,
it will sink to the ground,
and breathable air will be pushed upwards.
Not to mention,
reaching higher ground
will also help you avoid the rushing waters.
You're on higher ground,
but now you're trapped.
Below you are
carbon dioxide and
rushing waters from the tsunami.
You'll need to call for help,
and might be rescued by a boat or a helicopter,
depending on how severe the eruption is.
Now, you can finally leave
these treacherous conditions.
Phew. That was a close one.
But probably not as close as
surviving a pyroclastic flow, right?
Well, with our help,
you'll be able to conquer anything
on How To Survive.