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Life.

The closer you look...

...the more mysterious it seems.

We can't see the invisible forces at work.

But what if we could?

It's time to look at our home...

...in a whole new way.

Imagine carbon cycling through nature.

It's one of the building blocks of life...

...and it's stored in our forests...

...oceans...

...and grasslands

on an incredible scale.

But we've released too much of it into the atmosphere,

risking our future.

We can halt emissions and draw the carbon back down.

And our best ally for that is nature.

Restoring it to abundance

is the biggest challenge of our time.

But we CAN do it.

If the future of nature looked brighter,

so could the future for us all.

Our ocean.

It's the greatest ecosystem on the planet.

Standing by.

There might be a group going left to right.

- They just dove. - Roger that. Thanks.

Understanding how it works has never been so important.

- Over on the other side. - Right by that black boat?

- Yeah, I can see dorsals. - Yeah.

Because it's changing

under the pressure of climate change.

It's getting hotter and hotter, without a doubt.

And life within the ocean affects the whole planet.

Humpback whales are ocean nomads.

It's estimated they can migrate over half a million miles

in a lifetime.

Each summer, Atlantic populations come to feed

in Stellwagen Bank National Marine Sanctuary,

where marine biologist Dr Dave Wiley and his team

are ready to meet them.

There's a lot of activity, both commercial whale-watching boats

and recreational boats. So we have to work around them,

but we're looking for a group of two or three.

Dave's team wants to know how climate change

is affecting the humpbacks' feeding behavior.

To find out, they need to get much nearer to the whales.

You can't try to rush any of it.

That's why it takes sometimes, you know, long periods of time

before we actually get close enough.

It's a waiting game.

There's going to be a lot of this during this trip.

After looking for whales and working on whales,

eating is probably the next most common thing I do.

Such a good sandwich.

We're out here for like eight to ten hours at a time.

Of course, everybody gets hungry.

But we've noticed as soon as you start to snack,

that's when the whales pop up.

- Oh! - Look at that!

Whales coming up.

The scientists want to attach sensors to the whales

to collect important data.

It's not an easy task to put tags

on every animal in a group, but we've done it before

and we're going to try to do it again.

Looks like the group's coming up

over there at our one o'clock.

I have 403 here.

The tags we're using are called DTAGs.

They're a really sophisticated tag

that goes on with suction cups

so it doesn't hurt the animals at all.

So basically with these tags, we know what the animals

are doing with their body and we know any sounds they make

or anything they're hearing. And they're also

equipped with GPS so when they come to the surface,

they give us location. So it's really a full suite of data.

OK. Mike's ready to tag, everybody.

Hold on.

Here we go.

That was good. That worked well.

It all comes together, it's perfect.

Some of the tags are fitted with cameras

to see what the whales are doing.

So we've got this great backlog of data that shows us

what the ocean was like over the past 20 years,

how it's changing right at this very minute.

And then as this project continues into the future,

we'll know how the animals are behaving

in an ocean that's going to be really quite different

than the one they've been used to for the last...

...hundreds and hundreds and thousands of years.

And by deploying almost 300 tags since 2004,

they've built a picture of their feeding behavior.

This gives the scientists an important reference,

allowing them to see if anything unusual is happening.

Since the study began, the whales' feeding habits

stayed fairly consistent...

...until this year,

when Dave and his team noticed something different going on.

The main prey item for almost everything

in the Stellwagen Bank National Marine Sanctuary,

and humpback whales in particular,

are a little fish called sand lance.

They're maybe six inches long, as big around as your thumb,

and they're here in really big numbers.

Sand lance normally stay at the surface,

but this year they are keeping to the sea floor.

Dave thinks that rising ocean temperatures

are causing the fish to hibernate early.

We haven't seen this before, so this is already a sign

that the ocean is changing rapidly

and in many ways drastically.

What happens to whales matters,

as they play an important role in the ocean.

So these animals are going down and they're feeding

on the bottom, but they defecate at the surface.

They spread huge amounts of fertilizer

all over the surface of the ocean,

where the sunlight is also,

so you get this combination of fertilizer and sunlight.

This creates the perfect conditions

for a microscopic organism to flourish.

Phytoplankton.

Just like plants, they photosynthesize,

absorbing carbon dioxide.

And when conditions are right,

their numbers explode.

Carbon is now locked inside these giant blooms

instead of in the atmosphere.

They can become so huge

they are visible from space.

The more whales you have, the healthier the ocean is.

One of the really great things about humpback whales

is how successful they've been

in making a comeback from commercial whaling.

Some populations have recovered by as much as 90%.

If all the whales came back to fill the ocean,

the future would be brighter.

They're fertilizing the entire system

so there's more life here that can hold lots more carbon

and draw down carbon dioxide out of the atmosphere

where we don't want it, and into this ecological world

that we're looking at, which is exactly where we do want it.

But there's more to phytoplankton

and the role they play in the carbon drawdown story.

I wish more people knew about phytoplankton

cos they really are the unsung heroes of life on our planet.

Dr Stephanie Henson is a phytoplankton expert

at the National Oceanography Centre in England.

Hiya. Here's a little sample.

Thank you.

So the bucket that we collected this morning of water

probably contains more phytoplankton

than the population of London or New York.

There's plenty of phytoplankton and zooplankton in there.

Oh, nice. That's really great.

Oh, there's all sorts of stuff in there.

- Yeah. - Really nice. Great.

But of course, they're feeding the whole ocean, effectively.

They're the base of the marine food chain,

and everything else in the ocean depends on them.

Phytoplankton are eaten

by tiny creatures called zooplankton.

And they in turn are eaten by larger predators.

If there weren't phytoplankton in the oceans,

the marine food chain as we know it today

would completely collapse.

As species eat each other,

the carbon goes all the way to the top.

It's part of a process

that scientists call the biological pump.

To understand its significance,

we need to measure how much life there is in the ocean.

And that takes innovative thinking.

Marine ecologist Gael Mariani is crunching the numbers.

I know this code might look pretty boring,

but in fact it reveals something really fascinating

about fish, something we didn't even know about

three or four years ago in science.

And this research reveals really new information

about the role fish can play

in transporting carbon into a safe place.

So fish are able to store the carbon they eat

in their own bodies.

And you might say, hang on, it's not a lot

compared to a large species like some whales.

But it's biomass that matters.

How many fish there are.

By gathering data from the fisheries around the world,

Gael's results give an astonishing picture

of how ocean life helps us

in the fight against climate change.

So we've made some calculations,

and we found out fish of commercial interest

are able to draw down the equivalent

to the annual emission of 50 million American citizens.

It's massive.

Fish numbers are far lower than they could be.

By taking them out of our ocean,

we are reducing the power of the biological pump.

We can also work out how much carbon we've lost

through fishing globally,

and the numbers are quite remarkable.

We calculate industrial fisheries

has reduced the carbon drawdown potential

of fish of commercial interest by 50%.

As well as their carbon value,

fish have a market value...

...and 60 million people around the world

depend on the fishing industry.

So we really have to move toward a future where we change

how we value fish. Like this place just behind me,

who really cares about how they source their produce.

Most of the life we know in the ocean

inhabits the surface layers.

It draws the carbon in.

But the deeper the carbon goes,

the better it is for the planet.

The twilight zone is a vast part of the ocean.

It extends around the globe, from pole to pole,

anywhere that the water's deep enough.

If you go into the ocean twilight zone,

one of the most amazing things you'll see

is the incredible what we call marine snowfall.

These tiny particles - microscopic organisms,

debris of animals and plankton that have died

and are drifting down slowly through the ocean.

And as it's falling, it's helping the ocean

to draw that carbon away from the atmosphere.

These deep, dark waters may seem lifeless.

But there are creatures here

that look like they're from an alien world.

There are types of organisms

that just look completely different than those species

that we're used to seeing in the upper ocean.

Many are luminescent, so they sparkle like fireflies.

After many years of scientists

slowly learning about the ocean twilight zone, we thought

we had a pretty good idea how many fish might live there.

But recent methods using sonar have suggested

that we may have been way off, and there may be

ten times more fish than we previously thought.

Researchers from the Woods Hole Oceanographic Institution

are on a mission to recover an instrument

that's been moored 1,800 feet down in the deep ocean.

Winch left. Bottom depth is 2802.

It's been gathering information

for the past two years,

so should be full of scientific revelation.

So there's always a chance

that something can go wrong during the recovery.

The research is led by oceanographer Dr Andone Lavery.

This is the mooring that's been out for two years.

We are looking at the acoustic sonars

that are on the top of the... of the mooring.

There's a little bit of slime on it, but not a lot

considering it's been down there for two years,

so, uh, pretty exciting.

This giant acoustic ball

sends pulses of sound through the water

to paint a picture of what's happening in the dark.

We're interested in the fishes

in the ocean twilight zone, and their migration

from the deep waters down at about 600 or 700m of depth.

And as they come up to the surface at night to feed,

we're interested in how much carbon they basically consume

and draw down when they migrate back down to the deep ocean

during the daylight hours.

We think that this is probably the largest migration on Earth,

the largest movement of animals on this planet,

which happens daily

in this big wave around the ocean.

We're only just discovering the secrets

of the twilight zone...

...and its role in drawing carbon into the deep.

I'm in a really slick area. You got it?

Yeah.

OK.

Finally get the data.

A simple USB stick holds the precious files.

All the data is here.

This is awesome.

6,000 files.

Could you put them up on the big screen?

Yeah.

The reason we use acoustics in the ocean

to look at fishes instead of using cameras,

is that you can see quite a long way with acoustics.

With a camera, you can only see fishes that are very close by.

And we use that sound and that really strong signal

to count how many fish we're seeing,

and to characterize what kinds of fishes they are.

Studying this movement of life is a formidable task...

...but the team is making headway.

What we've learned about the Twilight Zone

suggests that it may help the ocean draw down

billions of metric tonnes of carbon every year.

As much as six times the carbon dioxide

emitted by automobiles worldwide may be drawn down

by the ocean with the Twilight Zone's help.

But it's very hard to study, and there's a lot of things

that we still don't know about it.

The race is on to improve our understanding of the ocean.

But it's huge.

It covers 70% of our planet.

There's only one way to get a truly global picture

of how it works.

The ocean is a challenging environment,

which is one of the reasons why we don't know

as much as we probably should about it.

Dr Laura Lorenzoni is a NASA scientist.

She's preparing for a historical rocket launch.

A mission that aims to see the ocean

in a way that's impossible from Earth.

So important, the world will be watching.

Right now, I'm getting ready because I'm going to be

part of that broadcast tonight for our mission

that we're launching to space.

This mission that we're launching is really going to

help us understand that connection

between the atmosphere and the ocean

and that carbon drawdown.

What do I do? Just stick it in my ear?

As this is my first broadcast,

I am obviously a little nervous.

What time do we start?

You are looking live at Space Launch Complex-40

on Cape Canaveral Space Force Station.

It is such an honor to be here with all of you

near and far and witness history in the making.

NASA has studied Earth's atmosphere in the past.

What is it that you hope to learn

that you didn't already know?

That is an excellent question.

So this mission is really going to be critical

to nail down some of the gaps of information that we have

in terms of carbon cycling.

We have a decent grasp on

the physics of this carbon drawdown,

but the one thing that we're not really 100% sure on

is the biological part which is carried out by phytoplankton.

This mission is going to be able to tell us

what kind of plankton and what species,

and some species are really important

and can sequester a lot more carbon

faster than other species.

Many on the PACE spacecraft team

now going outside to watch this launch.

Getting down to the final seconds.

15 seconds.

This mission has been in the works

for about two decades.

It has gone through the hands of many hundreds of scientists

and engineers, enabling us

to see the ocean in brand-new ways that we hadn't before.

Minus 10.

10, 9, 8,

7, 6, 5,

4, 3, 2, 1.

Booster ignition,

full power engines

and liftoff of the Falcon 9 and PACE, helping keep pace

with our ever-changing ocean and atmosphere.

Stage one propulsion is now go.

With every orbit,

this satellite will scan 30 million square miles

of the Earth's surface...

...identifying different types of phytoplankton...

...and where the most carbon-rich

expanses of ocean exist.

This mission is really going to move us forwards.

Because of the new measurements that this mission is bringing,

we have a lot of opportunities at our fingertips

to try to mitigate some of the changes that our presence,

our human presence, has induced on the planet.

We're about 10 seconds

from the engine cut off.

We can establish which parts of our ocean

are most important for carbon drawdown.

But they are often the most sensitive to climate change.

In the Southern Ocean, warming temperatures are affecting

a very different kind of carbon system...

...one so important it's studied by scientists across the world.

My name is Peter.

I'm a research director at the Flanders Marine Institute.

I'm an oceanographer.

So the Southern Ocean is the most remote ocean

of our planet.

Now, you can think about the Southern Ocean as a big lung.

It breathes in and breathes out carbon dioxide.

Atmospheric pressure pushes carbon dioxide

into the ocean surface,

a process called "the physical pump".

When it dissolves into the cold Antarctic waters,

it sinks down deep...

...where it can be stored for thousands of years.

We know today that the Southern Ocean

is one of the most important carbon sinks on this planet,

slowing down the rate of global warming this way,

but what we do not really know is how this is changing,

how this heat and this carbon uptake are changing over time,

how variable they might be,

and as climate change progresses, what we can expect

in the near and far future.

There are few places on Earth more difficult to study

than the Southern Ocean.

It's not for the faint-hearted.

But Peter knows someone who's always up for a challenge.

Yeah, yeah, OK. Let's go.

Boris Herrmann is a professional yachtsman.

Woohoo!

Yeah, yeah. Pause.

Yeah, I obviously love sailing and racing on the ocean.

That is my passion since my childhood,

and it became my job.

I really feel at home on the ocean.

OK, let's have a look outside.

Sea state is OK.

And full main!

Scientists need precise data

about the exact CO2 concentration

in the ocean surface.

This you cannot measure by satellites.

You need to go with some sort of vessel.

And there are no commercial ships here,

no cruise ships, etc.

Here in the Southern Ocean, us racing sailors,

we are the only ones.

Boris's boat gathers data as it sails.

Here's the ocean lab. So, basically,

there's a big pump here. I can...

If I put my hand on it, it's warm, I can feel it pumping

and I can hear the water flowing through these tubes.

It comes from the keel,

it goes through here and then goes back out into the sea.

So it permanently tracks water temperature, water salinity

and, most importantly, the CO2 concentration.

With Boris's help,

scientists will be able to assess

how the Southern Ocean is changing.

And what's really remarkable about the data that Boris

has collected is that he has collected data

in places where we haven't...

...we've never, ever collected

carbon dioxide measurements before.

I think the biggest gratitude for Boris

might be that his data will be used for a very long time.

So every measurement that is taken today

will not only be used tomorrow or in the next years,

it will be actually used indefinitely.

I'm very happy that we can use the attention

we get around this sport

to make people speak about climate solutions

and hopefully inspire people around this topic

and hopefully have a positive influence with this

because we have no choice. It's a race we must win.

We shouldn't take it for granted,

because if we don't protect those natural carbon sinks,

may they be on land or in the ocean,

we will not have this service in the future

and will be a much bigger problem.

We want to keep a close eye on the climate system,

how it behaves, how it changes,

because there are so many things that we may not know,

and so many changes that we might otherwise overlook,

and so we want to understand our future we're heading to.

Across the seas of the world,

signs of what's in store are becoming more frequent.

One of the great advantages

of being here is that the Mediterranean

is a laboratory for the world.

So the Mediterranean is undergoing remarkable changes.

Its temperature has never been hotter.

The last few years we've had extreme marine heat waves.

And so what we see when we look at the Mediterranean

is a glimpse of the future for the rest of the planet.

If we don't figure out how to stop the climate

from changing more,

if we don't figure out a way of drawing down carbon,

if we don't find a way of working with nature,

I don't know exactly what the future will look like,

but this is the place where we will find out first.

The ocean draws down one-quarter

of the 11 billion tonnes of carbon that we emit each year.

Extreme temperatures are compromising

this critical system.

Giulio's work models these effects

to help us avoid the worst, and prepare for what is coming.

I actually think that nature has been

trying really hard to help us.

Now, it can't do that by itself.

It can't solve all of our problems by itself.

We have to stop emitting,

and we have to help nature do what it does.

So the quest here is, can we transform that nature?

Can we power it up so that, while we stop emitting,

it then helps us draw back down

the stuff that we put up in the atmosphere in the first place?

Restoring life in our ocean is a huge task.

It takes collaboration...

...determination...

...and innovation...

...and some brilliant projects are already under way.

40% of us live along the coastline... for good reason.

On this small island in Kenya,

nature is still abundant.

It's a favorite spot for local fisher Hassan Shee Yusuf.

What makes the catch so good here

is the surrounding mangrove forest...

...an ecosystem of tangled roots

that only exists where the land meets the sea.

Working alongside local fishers

is marine biologist Mwanarusi Mwafrica.

What I love much about the mangrove forest

is because this is an ecosystem that actually provided me

with a job.

Like my daily bread, yeah!

Mangrove roots are very essential because they provide

a safe haven for juvenile fish

from being carried away by strong waves.

So the fact of having more trees, this means you're going

to have more fish, more fish in the future.

Mangrove forests grow along many tropical coastlines.

And when it comes to harnessing carbon dioxide,

they are a superpower.

These are very magical trees because the services

that they provide are quite diverse.

Mangroves are very efficient at drawing down carbon.

When we look at the capacity,

it's almost seven to ten times

compared to other terrestrial trees.

The interaction between the trees, the tide and the mud

creates a unique environment...

...that not only means mangroves can store more carbon per acre

than any other type of forest on Earth...

...they keep it locked up for millennia.

But many mangroves have been lost to deforestation

and coastal development...

...including here in Kenya.

But the community here is now turning things around...

...through a new business venture.

So Vanga Blue Forest

is part of a carbon-offsetting scheme.

So what happens is that individuals, companies,

businesses come to offset with the project,

in the essence that they are promoting conservation efforts

as much as they are offsetting their own carbon emissions.

If we fund nature now,

these ecosystems will continue to draw down carbon

long after our emissions have ceased.

Since the project started,

over 4,000 mangrove seedlings have been planted.

Carbon drawdowns of Vanga mangrove forest

are at 6,000 tonnes a year.

Carbon sales are also enriching the community.

The local school now has a science lab,

and better facilities

have helped its first student get to university.

What makes me to be very proud

working at Vanga Blue Forest

is the fact that I'm at the focal point of a change,

the focal point of a movement that is growing globally,

and that movement is changing the narrative

of reversing climate change.

Pioneering projects like this

show how we can boost nature and carbon drawdown.

But to really transform our ocean,

we need to work at scale,

which requires even more investment.

I'm Julie Robinson and I'm the Belize Program Director

for the Nature Conservancy.

This story does not start in nature,

it actually starts in a boardroom.

Belize had a long history of being indebted.

That actually became worse during the COVID-19 pandemic,

and tourism came to a screeching halt.

And so, essentially,

we were in an economic crisis,

and we also had a debt payment looming.

But Julie and her team were working on a plan

that was about to turn this crisis into an opportunity

to invest in nature.

But I've spent way too much time in boardrooms like this

looking over Excel sheets and on computer.

What I'd really like to do is take you out on the ocean

and show you exactly what we're protecting.

So right now we're in San Pedro, which is

a really popular tourist destination.

It is a biodiversity hotspot,

great for diving, great for snorkeling.

It was actually my childhood out here that led me

to be where I am today...

Right over here looks good.

...and at six years old, I pretty much decided

that I was going to dedicate my life

to saving the animals in the water.

In today's warming ocean,

this beautiful reef needs all the help it can get.

But conservation at this scale is expensive.

Hard to prioritize when you've got a large national debt.

But Belize had a plan.

We call it Blue Bonds for ocean conservation.

You could think of it as refinancing

or remortgaging a home, whereby a bank is able to provide

better terms and reduce the overall payments,

and then the savings from that reduced payment

is what goes towards conservation.

In this case, that was a figure of $180 million US

to be rolled out over a 20-year period.

When you borrow money for your home,

it's an investment, right?

You renovate, you look after it,

and over time, it adds value.

The challenge was really coordinating

all the various players, all the partners,

because something of this scale

had just never been done before.

A big team effort was needed

for this ground-breaking deal

to protect mile after mile of ocean.

And for its part of the bargain, Belize had to commit

to some serious goals.

Protecting 30% of waters would allow nature to thrive...

...and better management would support the people who rely

on a healthy ocean.

And look at it.

When it's working, it is absolutely paradise.

Once the decision had been made to move the deal forwards,

it took only 18 months to get everything in order,

and now there's a model for other countries.

Around the world, more projects like this

are in the works,

thanks to the success of this inspirational deal.

During a time during climate crisis,

we need things like this more than ever before.

When nature wins, we win,

and so does the carbon drawdown.

But two-thirds of our ocean, known as the high seas,

fall outside of national laws.

Without governance, fishing can be a free-for-all.

To protect nature in these unmanaged waters

takes international collaboration...

...based on accurate scientific information.

Ecologist Tristan Rouyer is hoping to spot

one of the world's most valuable fish from the sky.

Buckle up and let's go.

Tristan is joining Scientific Angler,

a fleet of recreational fishers

competing to catch a tuna for science.

The Mediterranean Sea

is home to one of the most important

Atlantic bluefin tuna fisheries in the world...

...making it a prime spot to monitor numbers.

Demand for bluefin surged in the 1990s,

which led to their rapid demise.

But against the odds,

these highly prized fish are making a comeback.

Fabien!

The competition is on!

Small tuna like this are the optimum size for tagging.

The tag has been programmed to last for over four years.

It will show Tristan exactly where the tuna goes

as it heads out to unprotected waters.

Perfect.

The resurgence of bluefin tuna

can't be taken for granted.

Keeping their numbers up requires collaboration.

And Tristan's data feeds into an international coalition

of over 50 countries and governments

committed to preventing overexploitation in the future.

If Atlantic bluefin tuna can come back from the brink,

surely there's hope we can return

even more nature to abundance.

In an ocean bursting with life,

carbon can be drawn away from the atmosphere.

Carbon is it... It's the...

It's the thing of our time, right?

It's the challenge that all of us have to face.

Climate change - it's something that we have done,

but it's also something that we can fix.

No matter where we live,

the nature that surrounds us can be restored.

As a project lead, it gives me the boost

to always look forward

to every morning waking up with an open heart,

because it gives me the determination

that whatever I'm doing brings change.

But it's not just down to you and me.

The world needs to act and boost our entire living planet.

It's a race against time

to find solutions for climate change.

We have a choice to build the world we want to live in.

So if we can find a way of investing in nature,

of working with nature...

...I think we'll be able to overcome even this,

which is the greatest challenge of this century.

The future I want is a future where this sanctuary is filled

with whales and filled with sea birds

and fish and just life,

and so I want to make sure that this sanctuary stays this way.

I want this place to be like this, you know, for ever.

And for ever depends on the future of nature.