Episode 3 Blow Your Mind

We are Dr Chris and Dr Xand van Tulleken

-and we're tracking down the most awesome...

-Incredible...

..and epic things in the universe!

Come with us and discover unbelievable things...

that will blow your mind!

Blow Your Mind will be bringing you loads of top experts

and scientists to help you find out more about some amazing stuff.

From the Arctic to elephants, spaceships to sharks,

and this week, it's all about ice. Yes, frozen water.

-So hold on to your brains.

-Here's what's coming up.

Today we explore an incredible

and dangerous underground world of caves and tunnels...

..play pooh sticks in a glacial river...

..and get up close to a cute little arctic fox.

Now, icebergs are incredible.

They're born - or carved - from glaciers,

but one of the amazing things for me is their massive size,

the sheer quantities of ice involved.

That's right, millions of tonnes of ice,

mile upon mile of the stuff, just making its way to the sea.

Now, massive icebergs are actually called mega-bergs

and I joined a bunch of scientists

and lived on a glacier for three weeks in Greenland to find out more.

-Now, Xand, do you have any idea what a moulin is?

-Why yes, I think I do.

A moulin is basically the French word for a windmill.

Erm, well, yes.

A windmill can be a moulin,

but the exact translation is a grinder.

In the world of glaciers, a moulin is a gigantic hole in the ice

which has been ground out over time by water.

Like most things to do with glaciers and icebergs,

they can be absolutely massive.

Gosh, Chris, well, you must have been very brave

to go in one of those on the expedition.

Oh, well, I am brave, yes, but I didn't actually go down it.

I left it to the experts,

because they had a good scientific reason to go in there.

Take a look at this.

There were over 20 scientists and experts on the expedition

but these are the main people you'll meet today.

Chris Packham, wildlife and nature expert.

Expedition doctor and all-round brave guy, me.

Helen Czerski, physicist and oceanographer.

Andy Torbet, extreme explorer and glacial diver.

Michelle Koppes, glaciologist and ice expert.

Mark Neal, computer scientist and electronics expert.

The team headed to the middle of the glacier.

They had already carried out experiments on the huge blue lakes,

here, but still had some unanswered questions.

I'm a little bit sceptical that all the water can get

all of the way from the surface, all the way down to the bottom.

They were going to explore one of the many super-sized holes,

or moulins, that form on the glacier.

These were once plugholes for massive blue lakes that have

now cracked and drained.

So these are like big drainpipes going down

-and the question is - how far down they go?

-Exactly.

Expert ice climber, Andy Torbet,

intended abseiling down into this gigantic hole.

He'd be the first person to ever descend into this moulin.

This was an incredibly dangerous task, Andy had safety ropes attached

in case he fell, but the ice was so unpredictable, bits often broke off.

DISTANT RUMBLE

Big rumble, just then. All the walls are pretty unstable.

There's all these big icicles and big, like, snowflakes,

so the quicker we get down and out, the better.

The biggest risk for Andy was from those colossal pieces

of over-hanging ice that could detach

and smash into him on the way down.

I get so tense watching this, it's so exciting and scary!

I was very tense there on the day.

People said that Andy was brave,

but I'm not sure he wasn't a bit foolish.

It was incredibly dangerous.

Andy always seems to be the guy that does the dangerous things.

Well, that is what he's trained to do, but he is a careful guy,

so let's see what happened.

As team medic, I was very nervous.

I feel fairly redundant because, of all the things that can

happen to him, there are very few I'm going to be able to fix.

But Andy was making good progress

deep down in the moulin - but he was being very, very cautious.

I can see the floor beneath me.

Some of these huge blocks of ice...

Things as big as cars are lying down there.

And they weigh tonnes, and they've all peeled off from up above me.

So if that was to happen while I was hanging here, that would be it.

As Andy abseiled deeper down, suddenly,

he discovered something unexpected.

Whoa!

There's a massive, absolutely enormous

side passage.

You could drive a double-decker bus with another double-decker bus

on top of it and it would still fit through there, quite easily.

This tunnel was a crucial finding

because it would have drained the lake not downwards, but sideways.

This important discovery was only found

because Andy risked his life abseiling into the moulin.

And there's been no-one down here before us

and the chances are there will never be anyone down here again.

This is proper exploration. This is all completely virgin territory.

And this... This is the crowning glory.

This immense, cathedral-like tunnel.

Chris, I keep using the word amazing,

but that is truly, truly amazing!

I mean, the size of that hole is mind-blowing.

I don't know about mega-bergs, but that is certainly a mega hole.

It must have been awesome for Andy going down into it, knowing that

he was the first person ever to go there and almost certainly the last.

It's unbelievable to think you could get two double-decker buses

stacked on top of each other into that tunnel -

that's actually higher than the Channel Tunnel.

I know, but it was incredibly dangerous in there, too.

You heard Andy say that these pieces of ice at the bottom were

the size of cars, so if one of those broke off and fell

while he was in there...

Yeah, I don't think you'd catch me going down in there.

I can't wait to see more, though, it's nail-bitingly exciting.

Well, you might not want to go down there,

but we had to get the camera crew down so they could film it.

But just as they got to the tunnel,

they were reminded how much danger they were in.

LOUD BANG

BANG AND SOUND OF FALLING DEBRIS

-I think we should get out.

-Yeah. OK, got your gear.

That stuff up the top is not good.

The roof of the tunnel started to crack.

If it collapsed, it would have

buried the camera crew under thousands of tonnes of ice.

It was a tense race to get out.

But eventually they made it.

-I'm glad to be out of there.

-It was huge.

-Absolutely massive.

-And we got out, which is even better.

-Which is always nice.

That was terrifying!

-These guys are brave, aren't they?

-Yes, we are.

But that is the nature of exploration

and this is true exploration, in every sense of the word.

All right, Chris. Now, did they learn much

from what they saw down there?

Yes, they brought back vital information

about the side tunnels and how they take meltwater away.

But the team still wanted to find out more.

The team already knew that melted ice water forms blue lakes

which drain to the bottom of the glacier, helping it move.

But now they'd discovered that water doesn't always drain

straight downwards - sometimes it takes other routes.

The glacier has an immense hidden water system, a huge network

of tunnels that carry vast amounts of meltwater

through the ice sideways.

Now that we've seen this moulin,

we've seen that it's not a simple picture.

It's not straight down the plughole to the bottom,

it's much more complex.

Water goes down a little way, then maybe it goes sideways,

then maybe it falls down a bit more,

eventually all going towards the sea

but getting there by a huge variety of different routes.

Helen, Alan and Michelle wondered

if these side tunnels play a part in the creation of mega-bergs,

so they decided to try and trace the route of the meltwater

through the tunnels out to the front of the glacier.

We found a moulin that's about 8km up from the ice front

and it looks like the water that's flowing down into this moulin

is making a direct connection down to the north side of the ice front.

To track the route, they decided to chuck 30 plastic balls called

cryospheres into a moulin.

Even though these balls look a bit home-made, they're actually packed

with electronics which will measure their speed and the water pressure.

It looks reasonably likely that the water that's flowing past us

here will, at some point, flow out of the glacier front that

-we've been watching for the past week or so.

-Exactly.

So if we can find these at the other end,

lots of useful information is going to come out of them.

Unfortunately, even though the balls were packed with electronics,

they didn't have GPS, so we'd all have to search for them

-at the other end.

-Off it goes.

Whoo-hoo!

Far be it from me to criticise these very clever scientists,

but isn't this just a rather thinly-disguised

game of pooh sticks?

Well, I suppose that's like what they're doing,

but it's really useful

because it helps them to find out the route that the water takes.

Hmm, and they can have a really good game of pooh sticks

-while they're at it.

-I don't think they're thinking

about playing games, this is

serious stuff that could help prove or disprove their theories.

Dr Mark Neal designed the cryospheres and,

after they'd all been chucked into the moulin,

he joined the search to try and find them.

The problem was that the glacier's ice front was 8km wide

and the balls could come out anywhere.

So Mark took to the sky to try and track them down...

..whilst Chris Packham took to the sea.

-Hello.

-Just having a look at the ice field.

-Well, good luck.

My eyes are bleeding down here.

But no-one was having any luck.

No sign of any orange things.

If they've come out, or if they're going to come out -

they probably have come out by now...

I'm not going to tell you how many hours we've been out here now,

looking for these tiny orange ping-pong balls

which are packed full of this scientific paraphernalia,

but we haven't found them.

It became obvious this experiment had been less than successful.

So, Chris, erm, are the words "less than successful" a scientific term?

What do you mean, a scientific term?

I mean, the scientific term for a failure,

like, the failure of the orange ping-pong balls.

It sounds a bit like a movie,

The Failure Of The Orange Ping-Pong Balls,

coming soon to a glacier near you.

Very funny, but you're wrong, it wasn't a complete failure,

but it was a little bit less than successful.

Less Than Successful, coming soon to a...

Look, there was a lot of interesting stuff

that came out of that experiment and that's the way it goes in science,

sometimes you think one thing will happen

and then something different happens.

All right, I take your point.

Now, when we all got back from a hard day throwing ping-pong balls,

we were all famished,

but Chris Packham decided to do something else instead.

We'd just started tucking in to a hearty meal

when we observed a little visitor.

Chris Packham couldn't help himself

and decided to share his dinner with one of the locals.

This little arctic fox has been coming into our camp

almost every day, on the scrounge for food, of course.

But then, things aren't easy up here, there's not a lot of food about.

They feed on young birds they find in the nest, ptarmigan, hare,

that would be a pretty special day.

I have to say, a lot of people haven't taken a shine to the fox,

they come up with these stories about them breaking into the tents

and chewing all the cables, I can't see it, myself.

In the winter, it'd be bright white and they have an amazing winter coat.

Of course, they are a bit different than our foxes,

much smaller, of course,

blunter nose, smaller ears, shorter legs.

That's all about conserving heat when it's cold, here.

Hey.

Come on, you're going to get me into trouble.

I'm going to get told off for encouraging you into the camp.

I don't care, though. I'd rather have the fox than the food.

That's typical Chris Packham, isn't it?

He'd rather play with the animals than have dinner.

To be fair, that was a cute little thing.

It was, but you had to keep an eye on it so it didn't

chew through anything really important.

You greedy guts could have given him more food and then

he wouldn't have had to chew through your cables.

-Anyway, it's time to go.

-What, already?

So join us next time so we can blow your mind.