Original subtitles

(playful music)

Talking about the weather is our national past time.

We're always complaining about it, second guessing it

and leading up to the summer holidays,

we obsess about it.

And why does the weather report always seem to say

that it's going to be a beautiful sunny day

and then the next thing you know,

(pours)

In this episode, we're going to be looking

at extreme weather.

What happens when you stand in the freezing cold?

I'm about point three degrees away

from actual hypothermia.

Torrential rain, should you walk or run in the rain,

if you want to stay dry?

And I try and stand up to hurricane speed winds.

(dramatic music)

I've always been fascinated with how the world works

and I've got lots of questions about why things happen,

to find out the answers,

I'm gonna blow stuff up.

The weather today was a never to be repeated,

once in a lifetime experience, actually in the history

of the world, there haven't been two days

with exactly the same weather.

That's what makes it so complicated and chaotic,

an infinitely varying combination of three factors,

pressure, temperature, and humidity combine

to give us our weather

and by manipulating those conditions,

I can make a cloud appear right here in this box.

To do that, I'm going to need water vapor,

luckily, already in the air, I'm also going to need

something you may not expect, dust,

because that gives the water vapor something

to condense around.

Luckily that's also inside the box and finally

we're going to lower the temperature.

How I'm gonna do that, is I'm gonna pump a load of air

into the box and then I'm going to release it

allowing the air to rapidly expand, and cool

and then hopefully, instant cloud.

That's a cloud.

But this cloud isn't gonna make rain.

And I need rain for my next important question.

The question of whether you should walk or run

if you're caught out in the rain,

is something that's plagued philosophers and physicists

for millennium.

In the walk camp the argument goes that you'll get hit

by less rain drops if you're not running

into a bunch of them.

Whereas in the run camp the argument is that you'll spend

less time in the rain so you won't get as wet.

I'm gonna need a way to predictably measure the amount

of rain that I'm exposed to when I'm walking,

and when I'm running which means the obvious

and only solution is a business suit made of foam.

Now I need to make it rain,

queue the New Zealand fire service.

This is their rain making machine.

We've just got to gate is and work out

how much water we're giving him for the first one,

and then it's got to be exactly the same for the second one.

(laughs)

we've talked about that.

The firemen are trying to figure out a way

of keeping the rain consistent for both my walk

and my run.

So here's the basic plan,

I'm gonna proceed down the track for about 30 meters,

while the New Zealand fire service simulates

the rain storm directly above me.

First time I'll walk, second time I'll run.

Then when I get down to the end I step up onto my scales

which have already been zeroed to subtract

the weight of myself and my suit when it's dry,

so it's just gonna measure the extra weight of water

that I've picked up as I'm traveling down.

But because one measurement isn't enough,

I'm then gonna take the suit off,

put it into our press, squeeze it and then the water

will come out into this beaker at the bottom

which provides our second accurate reading.

I'm not a fast runner.

(laughs) And I've got a big foam suit on.

So I aint gonna be doing Hussein Bolt, that's for sure.

Right, we'll try and see what happens.

While the suit may look razor sharp,

in practice it's very, very impractical.

Good.

Okay.

Right, so, experiment number one,

walking.

Three, two, one, water.

(light music)

We'd be the first to admit this is not

a completely rigorous scientific test.

Alright, so that's walking,

two point five one five KG's.

So there we go.

522 mils, squeezed out of my suit from the walk.

Now it's time to try running with the fire service

providing the exact same amount of water

as during the walk version.

Right, that's running,

one point eight seven five.

So there we go, it's about 404 mils squeezed out

of my suit from the run.

So let's tally it up.

Walking soaked the suit with two and a half K's of water

but running was less than two.

And in the squeeze method, I got hit by over half a liter

of water but when I ran I got hit

by 100 mils less.

Not the world's most stringent experiment

but it does seem running is the way to stay dry.

So if you're caught in the rain,

the science would suggest that you're best to run,

I'd suggest you just get a brolly.

And now it's time to face some more terrible weather,

I want to create a hurricane so I'm going to need wind

and lots of it.

And for that,

I'll need a crash helmet.

(upbeat music)

I want to find out what it's like to be in a hurricane

so I've come to Wellington.

Wellington is the windiest city in the world but why?

Well, basically the wind is how the Earth moves the heat

from the tropics through to cooler parts of the globe

to try to keep that thermostat evenly balanced.

Now, at the moment we are gusting between

50 to 60 kilometers per hour but the highest wind speed

ever recorded here was 250 kilometers per hour

which was easily a category five hurricane.

A category five is the strongest possible hurricane

and that's when winds are averaging

over 200 kilometers per hour.

But I can't stand around all day waiting for that.

I'm going to build my own.

The specs say that this thing

will create hurricane force winds.

My face is now in a category five hurricane.

Okay I know what you're saying.

You and your special effects slow motion camera,

just because it's blowing a stream of air hard enough

to flap your jowls about Nigel,

it isn't the same as a hurricane.

It isn't going to blow you over is it?

(dramatic music)

Well, I have a cunning plan.

Maybe one leaf blower won't do it but what if I get

a whole bunch of leaf blowers?

Can I create winds strong enough to knock me off my feet?

I ran my plan past physics professor Stewart Bradley

for a bit of expert comment.

When I measured that on my face,

it was about 170 kilometers an hour.

What will happen with a whole bunch of them?

Well you might expect you'll get nine times as much

but in fact it still, the air goes around you,

and so my guess is it might come up to 200.

I get the feeling Stewart doesn't think my plan will work.

It's working.

My stupid idea is actually working.

I'm having trouble staying upright.

And we've hit 200 kilometers an hour.

A category five hurricane but the force is localized

so it's possible to stay standing.

So, clearly, that felt quite a bit more

than just one, it was really hard to stand in it.

So you double the speed,

you're gonna get four times the force.

That's really the difference between before

when you only had one and now you got nine.

But the force wasn't strong enough to knock me

off my feet, to find that sort of devastating power,

I've come to the biggest climatic wind tunnel

in the southern hemisphere.

This is the Ford Motor Company's high security

test facility in Victoria, Australia.

Capable of generating winds of 200 kilometers per hour.

Steve Poehner is the wind tunnel manager,

and he tells me they've never put a person in here

at high wind speed.

So we're gonna tether you down to the floor here,

so we've got some straps.

It is very dangerous.

So the first test is to 100 kilometers an hour,

which is a category two storm.

It's pretty simple how this works,

a big fan blows a lot of air out of that big hole.

So this is a leisurely 20 K.

Piece of cake.

It's nothing.

50 K's an hour.

It's a bit blustery, it's not too bad.

All of us have experienced 50 kilometer per hour winds

but wind speed is exponential.

75 K's an hour.

Doubling the speed, means four times the force.

That's a bit of bluster.

You can properly lean in about there.

When I get to 100 kilometers per hour,

it'll be four times stronger than at 50.

100.

Ah yeah.

Ah that's quite fun.

About 45.

Yeah that's all good.

But I don't feel like I'm gonna get knocked off my feet.

So Steve that was 100 K.

What are your thoughts about going?

I felt pretty comfortable in that, you took that in,

it didn't feel like I was gonna lose my footing or anything

what's your thoughts?

I'd be okay to go to 120 kilometers an hour.

But like saying exponential rise,

so the difference between 100 and 120

is gonna be quite a bit.

Quite a bit, so the risks that we're gonna see there

is that it will actually take your feet out

from underneath you, and we'll end up falling

onto the floor.

And 120 that's gonna put us up to hurricane force winds?

Yup.

Right.

Okay.

This is uncharted territory for the tunnel.

So this is basically hurricane force winds this time.

Never been done before in here.

Nothing like being first.

(laughs)

I'm sure it's all going to go well.

Okay,

Ready to go?

I'm set.

50.

75.

100.

You can certainly feel this.

Now we're going for hurricane force,

here we go.

120.

So that's, that's hurricane force.

Man that's pretty strong.

You can see this, but really only just.

You can start to feel it pushing up on your knees,

it's quite good.

This is safer than an actual hurricane,

the consistency of the wind allows me

to lean into it, whereas the sudden gusts

in the real world are unpredictable.

Also in the real world are a million flying objects

trying to kill me.

So,

that was 10 times the power of our leaf blowers

and that's what it's like to stand in an actual hurricane.

And the force was awesome but

I wonder if I can convince them to go a bit faster.

So going over a 120?

Not with a person.

We can't do that.

Alright.

It's too risky.

Steve suggested we put something else

in the wind tunnel instead.

We tied the tent to sandbags, the equivalent

of being pegged at your campsite.

And now we'll hit it with 200 kilometer per hour winds

a category five hurricane.

Let's go to 50.

50.

Oh actually you see it's just pushing it now.

It's starting to flatten it out.

Yup.

And a hundred.

Hundred.

Starting to lose a bit of structural integrity there.

You know how your machine goes up to 200?

Can we just crank it all out see what that does?

Yeah.

(flutters)

See right, and that's why

you don't go camping in a hurricane because basically

it rips your tent to shreds.

I can see why Steve didn't want me standing

in such a destructive force.

But back in a low security freezer in New Zealand

there's no one stopping me from getting hypothermia.

(upbeat music)

I've been finding out about the kind of weather

we normally try to avoid,

the pouring rain, the incredibly windy,

and now I'm going to take on, the freezing cold.

My mum always said,

if you're going out wear a hat.

But how much difference does it really make?

I'm going to enter a minus 20 degree freezer

first wearing a hat and then without.

So we need to get some theme-sters one,

heart rate on and we need to get

your core temperature monitor.

Associate Professor Jim Cotter

is a leading hypothermia expert and he's here

to make sure that I don't die.

He'll be recording temperatures all over me,

including my core temperature.

Just gentle, just slowly, there's no hurry.

Which is measured by sticking a thermometer

up my nose down to my chest.

So, if you can imagine picking your nose

with an incredibly long finger,

that's exactly what it's, it's actually not painful

at the moment.

There were other important temperatures to measure,

This is rectal temperature,

it's better than your aural and better than tympanic.

Sound alright?

Well it's alright again, is a word you could use,

sure.

I think it's best if that one is installed off camera.

Good god.

Its time to enter the test facility

slash meat locker wearing a hat like my mum says.

Air temperature: minus 20 degrees Celsius.

So this is me.

Doesn't feel too bad yet.

It's a bit nippy.

I'll also be filmed with a thermal camera,

the warm areas are red.

My face is around 26 degrees and so we should be able

to track heat loss.

As you'd expect the core temperatures haven't budged

so what's happening at the moment is he's holding

his core temperatures up, they really haven't moved.

And as you'd expect fingers and toes getting coldest,

toes not too bad yet.

Basically how the hat works is that it traps

a layer of warm air, against my head.

And every other part of your body,

your surface blood vessels, they can constrict

and that stops the heat loss,

but in your head the blood vessels can't constrict

to if you don't have that insulating layer there,

you start to lose heat big time.

So at the moment, my head feels quite toasty warm.

Ish.

Vaso-constriction is a major way

the body tries to stop you dying of cold.

Blood sent to the important areas,

like the brain and heart to keep them warm

while the fingers and toes are left to freeze.

So he's losing tremendous amount of heat

off his face in particular and the hats protecting

a lot of it off the scalp.

So Nigel's been in there nearly an hour now,

his core temperature really hasn't even moved yet,

if anything maybe point one, point two of a degree.

Wearing a hat is protecting the head quite well.

So we'll get him out now.

I survive nearly an hour at minus 20 degrees

with only moderate discomfort.

My core temperature never changed but I'm not safe

just because I've left the freezer.

That cold blood's now starting to return in,

the esophageal continuing down.

So I'm on the verge of clinical hypothermia

at the moment?

About every second reading sort of dips in and out.

So yeah you're right there.

Wearing a hat it took nearly an hour

to reach hypothermic levels.

I've warmed up again, would I last as long

without my lovely, cozy, hat?

Here we are, home again.

In a minute that thing behind me is going to kick into gear

because it goes through these cycles.

It's currently defrosting,

I don't feel like I'm defrosting, but soon,

that compressor thing's gonna kick back in,

and then it just starts to, belt out cold air.

(blasts)

The thermal cameras shows I'm losing a lot of heat

through my head.

So, it's quite interesting without the hat

I'm not sure the data's saying,

but it certainly feels like I'm losing more heat.

My fingers are certainly starting to hurt

much earlier than last time.

The esophageal at least is headed down already.

It was in there for nearly an hour last time.

And his core temperature really didn't change.

His face temperature despite the fact it's so exposed

is still up above 20.

So he's dumping a lot of heat out through the head.

So, looking at this you can see

that my hand is super cold.

It feels super cold, you can tell that

'cause it's super painful.

And the bits of my head that are cold are kind of the areas

of vaso-contruct, rest of my head quite warm,

so super cold, quite warm.

I'm going to put my glove back on now

'cause that's now a teensy painful.

The head's more exposed than what the fingers are

and yet it's holding above 20

and the fingers are headed down into the sixes now.

He's saying his toes colder than last time,

quite look here, it's heading on down.

No wonder, it's down near 10 degrees.

That's four and a half degrees colder

than they got while wearing my hat.

Now, they feel like they're being stabbed with knives.

His esophageal temperature now,

which is the most sensitive one,

we'd expect it to show the first drop,

and it's starting now I think.

It's down at 35 and a half.

And if that really starts to gather momentum,

given that it's gonna carry on when we get him out

we want to get him out with a bit

of safety margin so, it's nearly time now I think see.

We wouldn't want it to go below 35.4

before we drag him out.

So,

with (laughs)

face issues,

so we're 42 minutes in.

I don't know it's about minus 20 or something.

Some of the symptoms of hypothermia are confusion,

memory loss, drowsiness, and mumbled speech.

I'm at 35 point something.

I'm about, point three degrees away from actual hypothermia.

I certainly feel it.

(knocks)

That's the knock, I'm gone.

The experiment over, it's time to remove the thermometers.

Without my hat my core temperature dropped markedly

and with this extra heat loss my extremities

my hands and feet got much colder.

Done, that's how you do it.

(laughs)

So listen to your mum and put a hat on.

(crashes)

Now you're fully prepared for your next holiday

in the elements.

You'll run in the rain, you'll pack up the tent

if there's a heavy wind warning,

and most importantly you won't stand around

in a giant deep freeze for an hour.

(soft music)