Episode 2 Operation Cloud Lab: Secrets of the Skies


Episode 2

Similar Content

Browse content similar to Episode 2. Check below for episodes and series from the same categories and more!

Transcript


LineFromTo

One of the world's largest airships is taking a team of scientists

0:00:110:00:16

and explorers on a unique expedition.

0:00:160:00:19

A voyage deep into one of the most mysterious and precious

0:00:220:00:28

environments on earth.

0:00:280:00:30

The atmosphere.

0:00:350:00:37

It's in every breath you take.

0:00:390:00:41

It is a home to life...

0:00:430:00:45

..and it makes the weather.

0:00:490:00:51

So, we have this dynamic bubble of air, constantly moving, constantly

0:00:520:00:58

changing and that's what we're here with Cloud Lab to explore.

0:00:580:01:02

This quest is taking the team coast to coast across America.

0:01:040:01:11

So far, they have experienced the powerful weather systems of

0:01:110:01:15

the Southern coast.

0:01:150:01:16

You can feel the energy in the air around you.

0:01:170:01:20

It's absolutely fantastic.

0:01:200:01:22

Now, they are heading across a different kind of landscape -

0:01:240:01:29

the deserts of the west to the Pacific Ocean,

0:01:290:01:33

to explore three key themes.

0:01:340:01:37

Oh, wow!

0:01:370:01:39

Life - they will investigate the relationship between life and the

0:01:390:01:43

layers of the atmosphere right up to the death-zone of high altitude.

0:01:430:01:48

We've got every reason to think that there is life up there.

0:01:490:01:52

And the more interesting question, I guess, is how much is there

0:01:520:01:56

and what's it up to?

0:01:560:01:57

Climate - they will experience the surprising way in which the

0:01:590:02:03

atmosphere can transform the ocean...

0:02:030:02:05

Another giant-sized animal. This whole place is like super-sized.

0:02:080:02:13

..and human impact -

0:02:160:02:18

the ways in which we, ourselves, are changing the atmosphere.

0:02:180:02:24

We've hard evidence that human beings are creating

0:02:240:02:27

their own weather.

0:02:270:02:29

Checks for take-off then, please.

0:02:400:02:42

INAUDIBLE RADIO CHAT

0:02:420:02:45

The Cloud Lab Team are setting out on the second half

0:02:550:02:58

of their epic voyage, heading west across the United States.

0:02:580:03:03

From Texas, they will journey from airfield to airfield through

0:03:070:03:10

the arid west before concluding the expedition on the Pacific coast.

0:03:100:03:17

But as they meet the desert, there's a dramatic change in the airship's behaviour.

0:03:240:03:30

Expedition leader, Felicity Aston, wants to know what's causing it.

0:03:300:03:34

What's happening with the movement?

0:03:380:03:40

We've suddenly started making really steep climbs and sharp descents.

0:03:400:03:44

We've just started getting some thermals now.

0:03:440:03:46

So we are getting these rising bubbles of air from the surface.

0:03:460:03:49

When we fly into it, it lifts the nose up then as we continue

0:03:490:03:52

it lifts the whole body up, and then as we move further it lifts the tail up

0:03:520:03:56

so we've got a correcting motion that pushes us back down again.

0:03:560:03:59

It's really quite steep. We're pointing to the sky one minute,

0:03:590:04:02

and then down at the floor the next.

0:04:020:04:04

It can get quite extreme at times, yes.

0:04:040:04:06

-You get used to it.

-Really? Like sea-sickness?

-Yes.

0:04:060:04:10

-You all right?

-Yeah.

0:04:130:04:17

Despite the discomfort, it's the airship's ability to fly with the

0:04:200:04:24

currents of air that allows the team to pursue one of their key themes -

0:04:240:04:28

the relationship between life and the atmosphere.

0:04:300:04:33

They want to know how conditions change through the different layers

0:04:370:04:41

of the atmosphere and how that impacts upon the life found there.

0:04:410:04:44

So, Felicity and atmospheric chemist, Dr Jim McQuade,

0:04:460:04:50

are fishing for life in the layer of air that is the most dynamic

0:04:500:04:53

and closest to the earth. It's called the boundary layer.

0:04:530:04:57

We've got two - we've got two different ones.

0:04:570:05:00

By flying through this layer, they hope to shed light on one particular family of creatures...

0:05:030:05:09

He's pretty gorgeous.

0:05:090:05:11

..insects.

0:05:120:05:13

Whilst we're familiar with the lives of insects close to the

0:05:160:05:19

earth's surface, some have another, little known existence higher up

0:05:190:05:24

in the atmosphere.

0:05:240:05:26

The team are going to try and discover whether they get

0:05:280:05:31

blown here accidentally or are they exploiting atmospheric

0:05:310:05:35

conditions found in its different layers?

0:05:350:05:38

Elsewhere, another Cloud Lab team member

0:05:500:05:52

is targeting a different layer of the atmosphere

0:05:520:05:55

and another kind of life.

0:05:550:05:56

Microbiologist Dr Chris Van Tulleken is setting out

0:05:580:06:02

to find living bacteria in the high altitude death zone.

0:06:020:06:07

And the microscope I want to do last, just because it is so dusty.

0:06:070:06:12

He's brought in a specialist researcher, Noelle Bryan, to help him.

0:06:120:06:16

I need to get a sample of sky that's ten times higher than the samples

0:06:180:06:25

we've got before. So we're going up to almost 30,000 feet from...

0:06:250:06:30

you know, the cloud samples were from about 1,000 and 3,000 feet

0:06:300:06:34

so we want to find out if there are bacteria up there

0:06:340:06:36

and that's what Noelle is very, very expert at.

0:06:360:06:39

With this experiment, Chris is hoping to build upon some remarkable findings of his.

0:06:440:06:49

Earlier in the expedition, he discovered that the skies are alive.

0:06:530:06:57

We've got evidence here that we've got bacteria in clouds

0:06:570:07:02

and that's right at the cutting edge of science.

0:07:020:07:05

Chris not only detected bacteria in clouds, he revealed that

0:07:050:07:10

they played a significant role in making rain. Now, he's looking

0:07:100:07:14

for life beyond the clouds, upwards of 10,000 feet

0:07:140:07:18

to a layer of the atmosphere called the free troposphere.

0:07:180:07:22

Far away from the influence of the earth's surface,

0:07:240:07:26

the free troposphere is cold, desolate and bone dry.

0:07:260:07:30

Even for bacteria, this is an extreme environment.

0:07:340:07:37

Every time you look for a place where nothing should be able

0:07:420:07:46

to survive, there's always a microbe that can take it,

0:07:460:07:50

so that's what we are looking for.

0:07:500:07:53

Who is the hardiest, who is the toughest?

0:07:530:07:55

Who can take the desiccation, the low pressure,

0:07:550:07:59

the increased UV radiation?

0:07:590:08:01

Humans are wimps. We have a small temperature range.

0:08:010:08:06

We have a very defined set of environmental conditions

0:08:060:08:10

that we can survive.

0:08:100:08:11

Perhaps not all humans are wimps.

0:08:150:08:18

The free troposphere is far beyond the flight ceiling of the airship,

0:08:180:08:24

so Chris and Noelle have enlisted

0:08:240:08:26

the services of former paratrooper, Andy Torbet.

0:08:260:08:28

The idea is that I'm going to jump

0:08:350:08:37

out of a plane at about 26,000 feet and parachute

0:08:370:08:42

all the way back down to earth, collecting samples as I go.

0:08:420:08:45

The experiment will involve Andy attempting a highly technical jump

0:08:490:08:53

called a High Altitude High Opening, or HAHO.

0:08:530:08:56

It's usually the preserve of elite, special forces.

0:08:560:09:00

There's a lot of problems with sky diving from

0:09:010:09:04

26,000 feet so people don't do it.

0:09:040:09:06

One. The air is so thin, it's very, very hard to get stable.

0:09:060:09:09

You need to get stable within 3-5 seconds in order to open your chute.

0:09:120:09:16

If you open your parachute any longer than sort of 5 seconds,

0:09:160:09:18

you pick up so much speed again because the air is

0:09:180:09:20

so thin that when you open you get what's called a hard opening

0:09:200:09:24

and that actually has enough force to break your spine.

0:09:240:09:29

Bearing in mind that when I open my parachute at

0:09:290:09:31

26,000 feet it's going to be minus 28, minus 30

0:09:310:09:35

so it's going to be bloody cold as well.

0:09:350:09:38

And the air is so thin, there's so little oxygen,

0:09:380:09:41

if you don't have an oxygen supply, like a mask on,

0:09:410:09:43

you're going to suffocate and die within about a minute.

0:09:430:09:46

So it's a fairly hostile environment.

0:09:460:09:48

Very little is known about life at the altitudes Andy is

0:09:530:09:56

reaching for but as we look for life beyond our planet, finding what

0:09:560:10:03

can survive earth's extreme habitats is taking on new significance.

0:10:030:10:09

It also requires a novel, scientific approach.

0:10:090:10:12

The principle is presumably going to be, Andy flies up.

0:10:170:10:20

He's got a petri dish or a growth medium dish.

0:10:200:10:23

He opens the lid.

0:10:230:10:25

Then closes the lid before he hits the ground and there's our sample.

0:10:250:10:29

But presumably it's a bit more complicated than that.

0:10:290:10:32

The idea is the same.

0:10:320:10:34

We're going to have a device that goes up.

0:10:340:10:36

It's going to open.

0:10:360:10:38

We're going to catch a sample, close the doors and bring it back down.

0:10:380:10:41

Only, instead of one surface of a Petri dish,

0:10:410:10:44

with these plastic rods we're able to have 40 different surfaces.

0:10:440:10:47

So, it's sealed. He goes up, opens it,

0:10:470:10:52

the air goes over and then before he hits 10,000 feet, closes.

0:10:520:10:57

Seal it back up.

0:10:570:10:59

And that's our sample.

0:10:590:11:00

Then we bring it back here and we can work out what it is.

0:11:000:11:02

And then we can do all sorts of different things.

0:11:020:11:05

A lot now depends on what Andy can achieve.

0:11:080:11:10

Over the coming days, he'll put the finishing touches

0:11:110:11:14

to weeks of preparation,

0:11:140:11:17

working with ex-special forces skydive master, Dane Kenny.

0:11:170:11:21

Two minutes.

0:11:220:11:24

Dane will supervise Andy as he jumps from increasingly high altitudes.

0:11:250:11:30

Acclimatising to the changing nature of the atmosphere.

0:11:300:11:33

Cloud Lab biologist, Dr Sarah Beynon, has joined the expedition

0:11:570:12:01

to further the survey of insect life.

0:12:010:12:05

-What time is it now?

-Seven...

0:12:050:12:07

For Sarah, it's yielding some surprising insights into

0:12:070:12:10

exactly which insects are found in the boundary layer,

0:12:100:12:14

and at what altitude.

0:12:140:12:15

Bear with me. So, that's a flea beetle.

0:12:180:12:21

And I haven't seen any data of these being found at altitude before.

0:12:210:12:26

We had no idea that these insects were up there.

0:12:260:12:30

A lot of what we do know relies on radar which tells us

0:12:300:12:34

what's up there in terms of the abundance but we have no idea

0:12:340:12:38

what makes that up so tiny insects like this,

0:12:380:12:41

we can't tell what species of insect are up there.

0:12:410:12:44

So it's only through deploying something like this

0:12:440:12:46

that we have any idea of what is flying at those altitudes.

0:12:460:12:51

Now, Sarah wants to seek out evidence for one particular relationship

0:12:550:13:00

between insect and atmospheric condition.

0:13:000:13:03

So I have a spare net, so I'll put that one in.

0:13:060:13:09

OK, thank you.

0:13:090:13:12

Can you record the altitude, as well please Jim, and the time?

0:13:120:13:15

What time is it now?

0:13:150:13:16

-Uh, 7:03.

-OK.

0:13:160:13:19

The aim is to roam the vastness of the sky to intercept

0:13:260:13:29

a noctuid moth, one of a family of different species.

0:13:290:13:32

To do so, they must first wait for nightfall and a radical

0:13:360:13:40

transformation of the atmosphere called the nocturnal inversion.

0:13:400:13:44

-How high are we now?

-Er, Nine hundred feet.

0:13:450:13:49

-Nine hundred feet?

-Yeah.

0:13:490:13:50

As the sun goes down, the air that sits above the earth cools

0:13:560:14:00

more rapidly than the air at high altitude and that can create

0:14:000:14:04

fast-moving streams of air.

0:14:040:14:05

Noctuid moths are believed to use this nocturnal inversion to migrate

0:14:100:14:15

as far as 600 miles in a single night

0:14:150:14:18

by selecting the most favourable air streams...

0:14:180:14:21

..but rarely have they been caught in the process.

0:14:230:14:27

Sarah aims to change all that.

0:14:270:14:29

The moths at this time of night should be making their way

0:14:330:14:36

up into the higher airspace to migrate.

0:14:360:14:40

-So we should catch them on their journey upwards.

-Yeah.

0:14:400:14:43

The airship's sensitivity to atmospheric conditions

0:14:460:14:50

pays dividends as it drifts with the air currents.

0:14:500:14:53

All they can do now is sit, wait and hope

0:14:570:15:00

that the moths are on their way.

0:15:000:15:04

Ooh a moth!

0:15:140:15:17

-No kidding!

-No there really is a moth, where did it go?

0:15:170:15:21

Hang on. OK, lights? I haven't got my net with me.

0:15:210:15:24

Shine a light somewhere and keep it there, to keep the moth to it.

0:15:240:15:27

A moth has flown in through the window.

0:15:270:15:29

I need to get a net, OK, thank you.

0:15:290:15:31

Oh, it's here, it's here!

0:15:350:15:37

-Whoa, whoa - gosh, where's it gone?

-There.

0:15:370:15:41

OK, could you grab the killing cloth please?

0:15:440:15:47

We've found a moth!

0:15:470:15:50

The net isn't collecting them, but it's just

0:15:500:15:52

flown in at 500 feet above the ground, which means they're here!

0:15:520:15:57

OK, we need to be careful as I need to know what species it is.

0:15:570:16:00

I think what we'll do is just shove the whole net in

0:16:000:16:02

to be on the safe side. Awesome!

0:16:020:16:05

Teamwork! Excellent!

0:16:070:16:11

PILOT: Ready for landing, OK?

0:16:130:16:15

Sarah will need to get the moth under better light to identify it.

0:16:180:16:23

Only then can she be sure if it's one of the migrating noctuid species

0:16:230:16:28

taking advantage of the night-time air.

0:16:280:16:30

For the airship's 15-strong ground support team,

0:16:360:16:39

the night has just begun.

0:16:390:16:41

After several weeks of flying, the airship has been venting helium

0:16:410:16:45

in order to adjust to different altitudes. Now it needs topping up.

0:16:450:16:49

Well, this is the second rack here we've probably got at least two more.

0:16:490:16:53

We've been here about an hour so far so maybe another couple of hours.

0:16:530:16:57

Taking care of the airship all the time - it needs constant attention.

0:16:570:17:02

It's a very demanding mistress.

0:17:020:17:04

Sarah is drawing together the haul of insects from the survey.

0:17:130:17:17

Already, she's discerning a difference between the insects that

0:17:170:17:20

travel by day and those that travel by night,

0:17:200:17:23

including the one that flew into the airship.

0:17:230:17:25

In the daytime, most of the insects we caught were small,

0:17:270:17:31

like this leaf beetle

0:17:310:17:32

and these insects would have been carried up by the

0:17:330:17:36

turbulent daytime air and would have been at the mercy of the winds.

0:17:360:17:41

Whereas at night-time, everything started to get a bit more

0:17:410:17:45

interesting and every single time we flew at night,

0:17:450:17:49

we caught migratory, noctuid moths.

0:17:490:17:52

We've got a fall armyworm moth here

0:17:520:17:57

and these moths, they migrate northwards in the spring

0:17:570:18:01

and summer to make the most of the agricultural crops that are

0:18:010:18:04

growing and they decimate crops such as corn and cotton and then they

0:18:040:18:09

migrate...well, we think they migrate southwards again in the fall.

0:18:090:18:14

But we know very, very little about this fall migration

0:18:170:18:21

so any individuals we find in the fall is really, really useful.

0:18:210:18:26

The study demonstrates how insects exploit the varying conditions

0:18:290:18:34

of the sky at different altitudes and times of day.

0:18:340:18:37

Other research suggests that insects exploit the dynamic nature

0:18:400:18:44

of the boundary layer on a vast scale.

0:18:440:18:48

So, in a 1km square patch of countryside surveyed over the course

0:18:480:18:51

of a summer month, as many as 3 billion insects pass overhead.

0:18:510:18:57

The question remains, how much life exists

0:19:030:19:06

beyond here in the higher atmosphere?

0:19:060:19:09

-Is that tight?

-Yeah, that's tight.

0:19:110:19:14

It's a question Andy hopes to soon help answer by undertaking

0:19:140:19:18

the HAHO jump. At more than 26,000 feet,

0:19:180:19:24

it will be the highest he's attempted yet.

0:19:240:19:26

Remember, the priority is safe parachuting.

0:19:270:19:32

So I know this is very important,

0:19:320:19:34

but we can't do that if you've got an issue with the parachute.

0:19:340:19:37

-Happy?

-Happy.

-Good.

0:19:370:19:40

-Right, let's get out there.

-Look at that.

0:19:400:19:45

Steady as a rock but I shoot with this hand.

0:19:450:19:48

You'll be fine, mate.

0:19:510:19:53

Andy will have just one attempt to get the precious air sample,

0:19:550:19:59

and with it, a chance of finding microbial life.

0:19:590:20:02

The weather is closing in and safe conditions

0:20:080:20:11

are unlikely to return for days.

0:20:110:20:13

Before going to altitude,

0:20:160:20:18

the entire team must flood their lungs with pure oxygen.

0:20:180:20:21

If not, there's a risk that the nitrogen in their blood

0:20:230:20:26

could form bubbles, leading to the bends.

0:20:260:20:28

Without this and other precautions against

0:20:330:20:35

the sub-freezing temperatures and desperately dry air,

0:20:350:20:39

Andy would be dead within seconds.

0:20:390:20:41

It raises the question of how ANY life, even bacteria,

0:20:470:20:51

can survive extreme altitudes.

0:20:510:20:53

The answer could lie in another form of microscopic life,

0:21:010:21:04

one that has an extraordinary adaptation to aridity.

0:21:060:21:09

These are things called tardigrades or water bears

0:21:120:21:16

and they are unusual because they're extremely small and they can

0:21:160:21:20

survive complete desiccation, so complete drying out and this is

0:21:200:21:25

a desiccated, a dried out tardigrade here magnified on the microscope.

0:21:250:21:30

They are in a state of almost suspended animation.

0:21:300:21:33

The chemical processes that drive life are at a virtual standstill.

0:21:350:21:39

But it takes just a few drops of water to re-animate it.

0:21:430:21:47

When you run water over it, you see the chemical reactions start

0:21:490:21:53

happening again, absorbing the water and is now very obviously alive.

0:21:530:22:01

And it's gone from chemically dead, chemically totally inert, to now

0:22:010:22:07

being, you know, obviously quite an adorable little living thing.

0:22:070:22:11

It's got little legs and kind of a little face there.

0:22:110:22:14

Whilst the transformation is plain to see,

0:22:170:22:20

the secret to the tardigrade's survival is what's happening within.

0:22:200:22:25

We think that the way the tardigrades survive those

0:22:250:22:28

environments is by being able to tolerate the DNA

0:22:280:22:31

and protein damage that comes from being terribly dried out.

0:22:310:22:35

What they have is very, very good DNA repair mechanisms.

0:22:350:22:39

Chris believes that bacteria at high altitude

0:22:440:22:47

may use these same repair mechanisms to withstand the aridity.

0:22:470:22:51

Finding live specimens will go a long way to suggesting as much.

0:22:550:22:58

That now depends on what happens when Andy meets

0:23:020:23:05

the vanishingly thin air.

0:23:050:23:07

If Andy can't get stable, he'll have to free-fall to where the air is dense enough to slow his descent.

0:23:330:23:39

God, he's got a lot to think about.

0:23:540:23:56

It's much, much more skilful than I thought it was.

0:23:570:24:00

Andy's botched the exit and is struggling to get stable.

0:24:390:24:42

Despite the poor exit, Andy managed to open his parachute within

0:25:150:25:18

the vital first few seconds.

0:25:180:25:20

Now, he has to gather the sample.

0:25:220:25:24

The box must be closed at 10,000 feet.

0:25:550:25:58

If not, he will expose the sample to the lower atmosphere

0:25:590:26:03

where life can more easily exist.

0:26:030:26:05

There he is.

0:26:300:26:32

The reason I get Andy to do this is because he's a much better

0:26:320:26:35

microbiologist than I am a sky diver.

0:26:350:26:38

Andy appears to have pulled off the job.

0:26:400:26:43

But there's one thing the team haven't foreseen

0:26:460:26:49

that jeopardises the entire experiment.

0:26:490:26:52

Oooh!

0:26:540:26:55

Now, the sample is at risk of contamination.

0:26:570:27:01

You all right, mate? How you doing?

0:27:010:27:03

It was a good landing.

0:27:030:27:05

What I wasn't expecting is my feet were dead.

0:27:050:27:07

-I had no blood in my feet.

-They were numb, really?

0:27:070:27:11

-Your shoes are freezing cold.

-Because I've been

0:27:120:27:15

sitting in this harness 20 minutes,

0:27:150:27:16

my legs were completely numb and they just gave way on me.

0:27:160:27:20

Well, never mind that, let's make this safe.

0:27:200:27:23

-Good. Right I'm going to get this to the lab.

-OK, mate, no dramas.

0:27:270:27:30

The sense of relief is just... It was weird.

0:27:330:27:36

You don't notice the kind of the amount of stress or pressure

0:27:360:27:39

that's on your shoulders that's built up over the last three months

0:27:390:27:42

until it's taken away.

0:27:420:27:44

And suddenly you're like... It's gone, we've actually done it.

0:27:440:27:47

There's an element of kind of disbelief we've actually

0:27:470:27:51

pulled this off.

0:27:510:27:52

I got to jump the HAHO

0:27:520:27:53

and I managed to pull it off without seriously

0:27:530:27:56

injuring myself or killing myself, so, er... It was really good.

0:27:560:28:02

No-one's ever done it like this before.

0:28:020:28:04

But you know, if you work out how much of the air up there we've

0:28:060:28:09

passed over the rods, we should get something sticking and all we want

0:28:090:28:14

to see is that there's something up there, you know it's... One

0:28:140:28:17

or two bugs and we can amplify them, grow them, work out what they are.

0:28:170:28:21

It's a lovely thought isn't it, this,

0:28:210:28:24

got a little bit of troposphere in here.

0:28:240:28:27

It's really nice.

0:28:270:28:29

-Noelle!

-Is this it?

0:28:300:28:33

That is it.

0:28:330:28:35

Did you think we were going to get this, honestly?

0:28:350:28:37

No.

0:28:370:28:39

Andy's slow descent through more than 16,000 feet

0:28:410:28:44

of high-altitude air has given Chris and Noelle the best chance

0:28:440:28:47

of finding microbial life.

0:28:470:28:51

It will require forensic precision to ensure it wasn't in vain.

0:28:510:28:55

It's worth explaining that while we do this, sterile air is

0:28:550:28:59

flowing from this all over this surface so that no bugs can get in.

0:28:590:29:06

So even if a piece of hair falls off Noelle's head,

0:29:060:29:09

it won't land on the sample.

0:29:090:29:11

This is what I do all day virtually every day in London.

0:29:210:29:26

And I think it puts a lot of people off doing science

0:29:260:29:29

because it seems super mundane but it isn't.

0:29:290:29:32

This is where we... This is where we get the answers.

0:29:320:29:37

The best bit is not the skydiving.

0:29:370:29:39

The best bit is the answers.

0:29:390:29:42

Now we want to have a look at it on the microscope.

0:29:420:29:46

And in order to look at it, we're going to stain it with another dye.

0:29:460:29:51

We're going to stain it with this stuff which stains nucleic acid

0:29:510:29:55

so, things like DNA. Again, only life has nucleic acid, so it'll

0:29:550:30:00

stain that and then we'll be able to see the objects more clearly.

0:30:000:30:04

Once the sample is stained,

0:30:060:30:08

any cells will reflect back the light emitted from the microscope,

0:30:080:30:13

showing up as tiny glimmers of green.

0:30:130:30:15

There you go. You see...

0:30:170:30:18

You think there's going to be nothing there don't you,

0:30:180:30:21

you're just looking in to blackness and then -

0:30:210:30:24

what I was hoping to see and what I can see - is every

0:30:240:30:28

once in a while you move the microscope and that's what you see.

0:30:280:30:31

You just get that little beacon of a green dot.

0:30:310:30:34

Just a little green glow.

0:30:340:30:36

And each of those little green dots - those are cells.

0:30:360:30:39

The amazing thing is it's one thing

0:30:390:30:41

seeing the DNA glowing in the right size and shape of a bacteria

0:30:410:30:45

but the fact that it's alive, that is a really peculiar thing.

0:30:450:30:49

To find dead bacteria up there yeah, maybe.

0:30:490:30:52

To find living stuff up there is such a harsh environment.

0:30:520:30:55

No oxygen, its freezing cold, low pressure,

0:30:550:30:58

-high winds, you know, no water.

-No water.

0:30:580:31:02

Amazing.

0:31:020:31:04

The experiment joins a growing band of scientific research into life high in the atmosphere.

0:31:070:31:13

The picture that is emerging is that life is far more robust than ever imagined.

0:31:170:31:22

And that opens up all sorts of possibilities

0:31:270:31:29

for the prospects for life

0:31:290:31:31

in other extreme environments beyond our planet.

0:31:310:31:34

PILOT SPEAKS OVER RADIO

0:31:470:31:52

The airship is heading to the desert city of Phoenix, Arizona.

0:32:110:32:15

What's drawing the team here is another of their key themes,

0:32:210:32:25

the way in which we, ourselves,

0:32:270:32:29

can change the way the atmosphere behaves.

0:32:290:32:32

Earlier in the expedition, Felicity and atmospheric chemist,

0:32:370:32:41

Dr Jim McQuade, uncovered the surprising link

0:32:410:32:44

between pollution, clouds and extreme weather.

0:32:440:32:49

So what we're saying is that by cleaning

0:32:510:32:54

up our atmosphere, we've allowed there to be more hurricanes.

0:32:540:32:59

They're now hoping that Cloud Lab will enable them

0:33:050:33:07

to get to the bottom of another question

0:33:070:33:10

about our impact on the atmosphere -

0:33:100:33:12

can cities make their own weather?

0:33:120:33:15

So, I've been looking at historical data

0:33:170:33:20

and you can see that Phoenix, in the last 100 years, has gone

0:33:200:33:24

from being a really small, agricultural settlement into a large, urban city.

0:33:240:33:30

In the same period of time, there has been a distinct

0:33:300:33:33

change in the amount of rainfall in the city.

0:33:330:33:36

There are areas of Phoenix that have had up to

0:33:370:33:40

a 12% increase in the amount of rainfall which is really significant

0:33:400:33:46

and it looks like there might be a correlation between the two.

0:33:460:33:49

So, we want to see

0:33:490:33:50

if we can unravel how the city might be creating its own weather.

0:33:500:33:54

It's difficult to imagine that a single city could interfere

0:33:590:34:03

with a process that unfolds on such a grand scale as the weather.

0:34:030:34:07

The rain that falls here has followed the same cycle for millennia.

0:34:100:34:14

Every summer, warm, moist air is swept up from the oceans

0:34:160:34:20

to the South. As this air meets the hot desert,

0:34:200:34:26

variations in the landscape drive pockets of air upwards as thermals

0:34:260:34:32

where the moisture cools, condenses and ultimately falls

0:34:320:34:39

in sudden downpours of rain.

0:34:390:34:41

Where this rain occurs should be fairly random...

0:34:470:34:51

..but something appears to be concentrating it upon the city.

0:34:570:35:01

To see why, Felicity is going to start by surveying temperatures in Phoenix and the surrounding desert.

0:35:070:35:13

I took several readings of the surface temperature and I was

0:35:190:35:22

getting between 37 and 38 degrees centigrade.

0:35:220:35:28

So, it's pretty hot down there,

0:35:280:35:29

it's soaking up all the heat from the sun.

0:35:290:35:32

For the city to be concentrating rainfall, it needs to be

0:35:360:35:40

hotter than the desert, driving extra thermal activity.

0:35:400:35:43

Meanwhile, Jim is surveying another factor that could be increasing rain - humidity.

0:35:520:35:58

A hygrometer gives an on-the-spot reading of how much water vapour

0:35:590:36:04

is being carried in the air.

0:36:040:36:07

The dry bulb was 24.5, giving

0:36:070:36:10

a relative humidity of 26%.

0:36:100:36:13

So, the air's very dry here, which is actually the definition of a desert.

0:36:130:36:18

It's nothing to do with temperature.

0:36:180:36:20

It's how dry it is,

0:36:200:36:21

so that's why Antarctica can be classified as a desert.

0:36:210:36:24

Unsurprisingly, in the desert, there's plenty of heat but no water.

0:36:270:36:32

But what really matters is how this picture compares with the city.

0:36:350:36:40

OK, another measurement next to an orange tree

0:36:500:36:53

and a lemon tree in someone's front garden.

0:36:530:36:56

It's not like back in Leeds - got an apple tree.

0:36:570:37:00

45% relative humidity.

0:37:060:37:09

It's very obvious that there's a lot more water available to be

0:37:100:37:14

evaporating into the atmosphere just from manicured lawns.

0:37:140:37:18

There are lots of sprinklers down here.

0:37:180:37:20

Increased humidity is a consequence of the millions of gallons of water

0:37:320:37:36

diverted to the city from the surrounding rivers.

0:37:360:37:39

I'm getting a real variety in surface temperatures.

0:37:420:37:45

So, if I take a reading from the road or a car park, it's pretty much the

0:37:450:37:51

same surface temperature as in the desert, but if I point the camera

0:37:510:37:56

at a garden or a swimming pool or a roof top, then it's a lot less.

0:37:560:38:02

So, on average, the surface temperature here will overall

0:38:020:38:07

be a lot less than the desert.

0:38:070:38:09

The city is more humid and a little cooler than the surrounding desert.

0:38:140:38:19

Despite these differences, there's no evidence

0:38:190:38:22

for the increased thermal activity that can explain the rainfall.

0:38:220:38:25

As the day wears on, that picture soon changes.

0:38:380:38:41

See, look, look, look, look! See the city...

0:38:480:38:52

-Yeah.

-.it's hotter than the desert.

0:38:520:38:54

OK, yeah, you can see definitely the boundary.

0:38:540:38:58

So that's the desert cooling down

0:38:580:39:00

and that's the hot city.

0:39:000:39:02

That's a really nice example of it.

0:39:020:39:04

Whilst the natural landscape has quickly cooled,

0:39:090:39:11

the camera reveals the city to have remained warm.

0:39:110:39:14

They've identified an effect called the urban heat island.

0:39:180:39:21

Earlier today we measured the ground temperature of the suburbs to

0:39:260:39:29

be 24, 25 degrees, and see I'm measuring 23, 22.

0:39:290:39:35

I mean, it's still as hot as

0:39:350:39:36

when we measured it in the middle of the day.

0:39:360:39:39

The city's surfaces are continuing to radiate the energy of the sun

0:39:410:39:44

they absorbed earlier in the day.

0:39:440:39:46

The question is whether the urban heat island is generating thermals.

0:39:490:39:53

If it is, they should be able to detect

0:39:550:39:58

an increase in temperature at altitude from the airship.

0:39:580:40:01

So, I've just had a look the temperature

0:40:030:40:06

and this is the temperature going down and that's going down simply

0:40:060:40:09

because the sun's going down, you know, we're turning the heater off.

0:40:090:40:12

So, this is the temperature over the desert

0:40:120:40:15

and this is the temperature over the city.

0:40:150:40:18

-Oh, wow, so this is where we hit the city?

-Yeah.

-OK, this is us...

0:40:180:40:22

this is the temperature over the desert and then

0:40:220:40:24

we hit the city limits and the temperature quite clearly goes up.

0:40:240:40:28

It's not a huge increase, you know, no more than half a degree,

0:40:280:40:33

but you can't argue with that. That's a definite.

0:40:330:40:35

Despite the difference in temperature being small, it's critical.

0:40:380:40:42

It's enough for us to know that the

0:40:440:40:46

air above the city is warmer.

0:40:460:40:48

So we've got this big parcel of warm air sitting over the city.

0:40:480:40:53

It makes a lot of logical sense that that air is going to start rising and

0:40:550:40:58

that's going to start convection and the consequence of that is weather.

0:40:580:41:03

So the increased rainfall in Phoenix could be caused

0:41:070:41:10

by the urban heat island effect.

0:41:100:41:12

It generates thermals over the city that force air upward where it

0:41:140:41:18

begins to cool.

0:41:180:41:20

That, in turn, can cause the vapour to condense

0:41:200:41:23

and form rain concentrated here upon Phoenix.

0:41:230:41:27

So, we've found

0:41:300:41:31

the connection we were looking for, between cities, and the increased

0:41:310:41:35

rainfall that Phoenix has been experiencing in the last 100 years.

0:41:350:41:40

And the really exciting thing about that is that we've hard

0:41:400:41:43

evidence that human beings are creating their own weather.

0:41:430:41:47

It's a finding that threatens to have far-reaching consequences.

0:41:520:41:56

Our world is increasingly urban and much of that urban expansion

0:41:570:42:02

is taking place in sparsely populated arid regions...

0:42:020:42:06

..with unknown consequences.

0:42:060:42:08

If you take an area of desert and build a city on it,

0:42:200:42:23

then that city is going to be much warmer than the desert it's replaced.

0:42:230:42:27

And it's going to have an overall warming effect.

0:42:270:42:30

So if you multiply that by all the cities being built in desert

0:42:310:42:36

areas, all this turning from desert land into green agricultural,

0:42:360:42:42

irrigated land, then it leaves another little hanging question,

0:42:420:42:46

whether this is having a much larger global effect on our climate.

0:42:460:42:50

The airship has reached the western edge of the desert.

0:43:030:43:07

Beyond here lies their destination...

0:43:070:43:09

..the mighty Pacific, where the team want to conduct their final

0:43:150:43:20

set of studies.

0:43:200:43:21

An exploration of how the prevailing onshore Pacific wind shapes

0:43:230:43:28

the wildlife of the entire Californian coastline.

0:43:280:43:31

And that includes the life below the ocean surface.

0:43:340:43:37

But first, the airship will have to overcome the Pacific wind.

0:43:420:43:46

We're so close to the end of our journey that we can

0:43:490:43:52

almost smell the Pacific Ocean.

0:43:520:43:54

But there's one last obstacle. These mountains behind me.

0:43:540:43:58

There's only one pass through these mountains for miles in either direction.

0:43:580:44:02

It's called Banning Pass and it's a bit of a problem for the airship

0:44:020:44:06

because it's so narrow. All the winds are funnelled through.

0:44:060:44:09

And the winds come from the west towards us so it's going to be flying

0:44:090:44:14

into the winds and if there's too much wind, it could take hours, days.

0:44:140:44:20

Perhaps we could even be waiting for a week

0:44:200:44:22

until conditions are just right.

0:44:220:44:24

Even if the wind is blowing a gentle breeze on the far

0:44:290:44:31

side of the pass, by the time it reaches the entrance

0:44:310:44:35

the funnelling effect can accelerate it to gale force.

0:44:350:44:38

We seem to be hitting a lot of turbulence.

0:44:480:44:51

The wind is gusting and coming down the valley here.

0:44:510:44:53

There's two big mountain ranges coming together to give us

0:44:530:44:56

just this one little gap down the middle, so it's much rougher air now.

0:44:560:45:00

So you are really having to fight to keep it level?

0:45:000:45:02

It's a continuous fight

0:45:020:45:03

but at the moment we're making slow progress.

0:45:030:45:06

OK, so what's our ground speed at the minute?

0:45:060:45:08

-About five knots.

-Five knots? 6mph.

0:45:080:45:11

It's very bizarre. We are in this unseen jet stream of air.

0:45:140:45:19

So these engines are going fast enough to propel us at 30-40 knots,

0:45:190:45:24

but unfortunately the wind's coming in the opposite direction

0:45:240:45:27

at 30-35 knots, so we're only making only 2 or 3 knots ground speed.

0:45:270:45:32

We've barely moved at all. About two miles in the last hour.

0:45:320:45:37

-Co-pilot:

-It's actually getting worse right at the moment.

0:45:370:45:41

We've actually stopped.

0:45:410:45:44

I don't think we're going to be going through today.

0:45:490:45:52

The vast wind farm here one of the largest in Southern California

0:45:580:46:02

is testament to the winds near-constant presence.

0:46:020:46:05

We're definitely starting to move forward.

0:46:110:46:14

Back there we were not,

0:46:140:46:15

now we are definitely moving forward a wee bit.

0:46:150:46:17

-CO-PILOT:

-Yeah, there we go. We are going it a little bit here.

0:46:170:46:20

Despite Felicity's worst fears it seems as though they have

0:46:220:46:26

chosen the right day to make their move.

0:46:260:46:28

Sarah has gone ahead of the airship to experience the power of the

0:46:500:46:54

onshore Pacific wind for herself.

0:46:540:46:56

We are going to do a little bit of scratching here,

0:46:560:46:59

when we are close to the cliff edge.

0:46:590:47:01

And scratching is doing what?

0:47:010:47:03

-Well, when we are very close to the edge of the cliff...

-Like this?

0:47:030:47:07

Yeah. Scratching is our term.

0:47:070:47:09

This is where the most lift is, close to the cliff edge.

0:47:110:47:16

Sarah and Kirk are being carried on a type of air

0:47:180:47:21

movement known as ridge lift.

0:47:210:47:23

As the onshore wind hits the cliff, it is diverted

0:47:250:47:28

and accelerated upward.

0:47:280:47:30

But the real reason Sarah is here is to see how this movement of air

0:47:310:47:35

supports life.

0:47:350:47:37

Home! Shanty!

0:47:370:47:39

Good girl.

0:47:410:47:43

-Oh, wow!

-Unbelievable, huh?

-Oh!

0:47:460:47:50

So this is Shanty, who is a trained bird

0:47:500:47:53

-and she's using the same updraught that we're using.

-Up!

0:47:530:47:57

Shanty is a Harris hawk.

0:48:010:48:04

A native to this region, they are so highly evolved to

0:48:060:48:09

fly on the movement of air from ridge lift to rising thermals

0:48:090:48:13

much of their flight time is spent soaring.

0:48:130:48:15

Wow!

0:48:180:48:20

You can really see her wide, fairly short wings

0:48:200:48:25

and that's an adaptation to soaring.

0:48:250:48:27

Look at her soaring up there now.

0:48:270:48:29

And it's great to see the sort of finger-tips of her wings that

0:48:290:48:32

she's using to control her flight.

0:48:320:48:36

It's a behaviour found throughout the family of birds called raptors

0:48:360:48:41

that also includes eagles and vultures, enabling them

0:48:410:48:44

to extend their range to vast distances.

0:48:440:48:50

It makes sense for them to use these up-draughts

0:48:500:48:52

so that they expend as little energy as possible when they are hunting.

0:48:520:48:56

Exactly. And the raptors own motto, like any good predator,

0:48:560:49:00

is the maximum amount of reward for the least amount of effort.

0:49:000:49:03

So if they can stay up without putting much energy into it,

0:49:030:49:08

that's great.

0:49:080:49:10

-Here she comes again.

-Goodness me.

0:49:100:49:14

Good girl!

0:49:140:49:15

Hang on, it's the Pacific, it's the sea!

0:49:430:49:45

You should have your bikini on, we should be there in swimming trunks!

0:49:450:49:48

We've made it.

0:49:480:49:51

-This is the ocean, we've made it.

-Fantastic!

0:49:510:49:54

So, Atlantic to Pacific.

0:49:540:49:58

It's not quite journeys' end.

0:50:000:50:04

The team have chosen this particular destination to explore

0:50:040:50:08

a surprising relationship between life and the Pacific wind.

0:50:080:50:12

-What's that there!?

-Ah, yes!

0:50:140:50:17

-What is it then go on?

-A Blue Whale.

0:50:170:50:19

-Is it really?

-Really.

0:50:190:50:20

-I've never seen a Blue Whale before. Look at that.

-Wow!

0:50:200:50:25

-Hang on, there's more than one.

-There's two of them.

0:50:250:50:30

These are just the first indications of what they have come to see

0:50:300:50:35

because the wind can make habitats in the ocean too.

0:50:350:50:38

This is Monterey Bay, California.

0:50:450:50:48

Beneath its gleaming surface is a uniquely fertile eco system...

0:50:510:50:55

..that makes this one of the most biodiverse habitats in the earth's oceans.

0:50:580:51:02

-There you go, there you go.

-There's two more of them right there.

0:51:220:51:25

-The charismatic megafauna.

-Charismatic megafauna.

0:51:250:51:29

Chris and Andy have joined local marine biologist,

0:51:290:51:33

Steve Lonhart, to understand how this rich environment is

0:51:330:51:37

created by the wind.

0:51:370:51:39

If you can imagine the wind which is coming from

0:51:410:51:43

the northwest, so kind of over our shoulder, moving in this direction.

0:51:430:51:47

As it moves that way,

0:51:470:51:50

it actually just pushes the warm waters of the surface off,

0:51:500:51:54

and then you get this really cool nutrient rich water that's coming

0:51:540:51:57

up from the bottom, right where we are, right here, coming up from

0:51:570:51:59

the bottom and that's sort of like...you can think of it like fertiliser.

0:51:590:52:03

Meaning dead sea lions, dead kelp,

0:52:030:52:06

anything that dies, birds, all falls to the bottom?

0:52:060:52:09

Falls to the bottom,

0:52:090:52:11

and it is broken down into all its little constituent members,

0:52:110:52:15

that eventually just dissolve into the water.

0:52:150:52:18

When the water comes up, its clear, which allows things like kelp

0:52:180:52:22

and seaweeds, to do what they do which is photosynthesise.

0:52:220:52:26

Just like plants on land nitrogen,

0:52:260:52:28

carbon, building blocks of life.

0:52:280:52:30

And instead of those things being in the air and the soil,

0:52:300:52:33

-they're dissolved in the water.

-That's right.

0:52:330:52:35

Then you have a forest, not on land,

0:52:350:52:37

it's actually on the shore.

0:52:370:52:39

To see the result of this process in its full majesty you have to

0:52:430:52:47

look beneath the surface...

0:52:470:52:49

..and to the unique environment that it creates.

0:52:500:52:53

The forest of giant kelp.

0:53:070:53:09

Not only does the kelp benefit from the nutrients drawn

0:53:120:53:15

up from the depths,

0:53:150:53:17

it is also bathed in the energy of the sun, allowing it to

0:53:170:53:21

reach 175 feet in height.

0:53:210:53:24

Ah, so these are the giant kelp.

0:53:290:53:33

You see the little bubbles?

0:53:370:53:40

Awesome, and that's what holds the giant kelp up.

0:53:400:53:43

-Chris, this is Andy.

-Go ahead. Over.

0:53:520:53:58

Every square inch of this entire system all the rocks,

0:53:580:54:05

the nooks, the crannies - are all teeming with life.

0:54:050:54:09

There's not a square inch that's left bare and barren.

0:54:090:54:14

There's life everywhere. Outstanding again.

0:54:140:54:22

How does this compare with other dives you've done?

0:54:240:54:29

This whole place is like a normal sort of temperate

0:54:290:54:33

reef but just much, much, much bigger.

0:54:330:54:38

Everything has been super-sized.

0:54:380:54:40

It's huge.

0:54:440:54:45

It seems like all the life

0:54:470:54:48

down there is scaled-up enormously because of this nutrient-rich water.

0:54:480:54:54

I've just seen the biggest anemone I've ever

0:54:570:55:01

seen in my life. It's huge.

0:55:010:55:06

I've never seen an anemone that I would consider a man-eater,

0:55:060:55:11

but if there ever was one, this is it.

0:55:110:55:14

This is probably the best sight so far. I'm coming up.

0:55:170:55:21

I'm rising up the trunks of these huge, giant kelp.

0:55:210:55:26

Whilst this may be a very special environment, it also

0:55:310:55:35

vividly demonstrates the power of the atmosphere to reach into every

0:55:350:55:40

corner of the planet and make it a place for life.

0:55:400:55:44

For me, it really provides an insight into just how complex the atmosphere is.

0:55:500:55:56

It's not just something that we breathe and that produces

0:55:560:55:59

weather, it has the ability to shape the landscape underneath it.

0:55:590:56:04

It plays a huge part in forming the environments in which we all live.

0:56:040:56:08

Reaching the Pacific brings to an end what has been an extraordinary

0:56:140:56:18

and unique adventure.

0:56:180:56:20

This epic journey coast to coast

0:56:220:56:25

has enabled the team to experience the atmosphere as never before.

0:56:250:56:29

That's the one I want! That one!

0:56:290:56:33

They've explored the extraordinary processes that generate weather...

0:56:330:56:39

-20 million.

-So, that small cloud weighed four tonnes?

-Yes.

0:56:390:56:43

-That's incredible.

-It is.

0:56:430:56:46

..they've seen some of the many ways that life - at every scale

0:56:460:56:50

from microscopic bacteria...

0:56:500:56:53

Now we are sucking in the cloud.

0:56:540:56:57

..to more familiar species exploit each level of the atmosphere...

0:56:580:57:03

Good luck, little one.

0:57:050:57:06

These waterfronts, they are vital for movement,

0:57:060:57:09

not just on a small scale, but on a global scale.

0:57:090:57:12

..and they've revealed the often complex mechanisms by which

0:57:220:57:25

we, ourselves, are shaping this realm.

0:57:250:57:29

-Cheers, everyone!

-Cheers, guys.

0:57:540:57:56

-Cheers!

-To the Pacific!

0:57:560:58:00

Download Subtitles

SRT

ASS