from BBC Learning English. I'm Neil.

And I'm Sam.

It's hard to feel positive when you hear about

climate change, don't you think, Neil?

Yes, according to the UN's Cop26 conference,

we're heading for a catastrophic

global temperature rise

of three degrees by the

end of this century...

Fires are blazing from the

Amazon to the Arctic...

And even if we stopped

burning all fossil fuels

tomorrow, it would take

decades to feel the effects.

It's all very depressing!

I agree, but there is hope

that catastrophes can be

avoided thanks to some amazing

ideas by some very imaginative scientists.

In this programme, we'll be

discussing geoengineering -

the name for a collection

of new scientific plans

to remove carbon from

the atmosphere and

stop global warming.

Also called 'climate repair', geoengineering

is still in the

experimental stages.

Some technologies are

controversial because

they interfere with

natural climate systems,

and others may not

even be possible.

One ingenious idea to cool the planet

involves spraying diamond dust

in the sky to deflect

the Sun's rays.

Amazing! But before we find out more,

I have a question for you, Sam.

Spraying diamond dust

in the sky sounds

futuristic, but in

the 1960s there was a

band who wrote a song

called 'Lucy in the

Sky with Diamonds'.

But which band? Was it:

a) The Rolling Stones? b) The Beach Boys? or

c) The Beatles?

I think most people would say the answer

is c) The Beatles.

OK, we'll find out the answer later in the

programme. Now, throwing

diamonds in the sky might

sound crazy but it's far

from the wildest idea

scientists have thought

up to decarbonise the planet.

Oceans hold sixteen times more

carbon than the Earth's

atmosphere and could hold even

more if the fish and plankton living there

had more available

nutrients - food that

animals and plants

need to grow.

But how to provide these nutrients? Believe it

or not, one answer

involves - you guessed

it - whale poo!

David King chairs the Centre for Climate

Repair at Cambridge University.

He explained how his

unusual idea would work

to BBC World Service

programme, Discovery:

Image now a pod of whales all

coming up and pooing in the

same area of the ocean.

This could be in an eddy

current, and it could

lead to something like

10,000 to 20,000 square

kilometres being covered

in nutrients, including iron.

And as we know from

observations today,

within three months that

region is chock-a-block with fish.

Whales live in groups called

pods. They swim up to the

ocean surface to poo, and

this poo can be spread

in an eddy - a large current

of water moving in a

circular motion, like

a giant whirlpool.

As a result, huge areas of

the ocean are covered in

nutrients, and become chock-a-block with

fish - an informal way to

say 'full of fish'.

Another original idea being

explored is 'rock weathering'.

Carbon is slowly locked into rocks

and mountains over thousands of years by

natural geological processes.

This literally ground-breaking

idea would speed up the

process by locking carbon

into rocks that have been

dug up through industrial mining.

Listen as geochemist,

Professor Rachael James, explains

her idea to BBC World Service's, Discovery:

For every tonne of rock that's mined, only a

very tiny proportion, a

couple of grams of that,

is actually diamond.

The rest of it is

effectively waste. So,

mine waste material is

potentially a really great

source of material that

could be repurposed for

enhanced rock weathering

and I think that's really

good because it creates

a circular economy.

Mining for diamonds creates tonnes of waste

rock which could be used

to capture carbon.

Professor James wants

to repurpose this rock -

to find a new use for it.

Not only would this lock more carbon, it also

creates a circular

economy - an economic

model which involves

sharing, reusing and

recycling products for as

long as possible to avoid

waste and to reduce

levels of carbon.

While these ideas might sound

strange, they're all theoretically possible.

And looking to science

for positive solutions

reminds some people of

the early ecological

movement which started in

the 1960s and now,

fifty years later, is

being taken seriously.

Speaking of the 1960s, it's time to reveal the

answer to my question, Sam.

Ah yes, you asked me which sixties band

wrote the song, 'Lucy in the

Sky with Diamonds'I

said, confidently,

c) The Beatles.

Which was, of course... the correct answer!

John Lennon and

Paul McCartney

wrote the song in 1967

but I doubt even they

could have predicted

that it would inspire

a scientific idea to

save the planet!

OK, let's recap the vocabulary from the

programme, starting

with nutrients - food

that plants and animals

need to grow.

Whales and other sea mammals like dolphins

live in a group

called 'a pod'.

An eddy is a large current of water moving

in a circular motion.

Chock-a-block is an informal way to say

'full of something'.

If you 'repurpose' something,

you find a new use for it - a use other than

what was originally intended.

And finally, the planet's future

might depend on the circular economy - an

economic system which

values sharing, reusing

and recycling over

consumption and waste.

These incredible scientific

innovations might mean that time is not yet

up for planet Earth - but

time is up for

this programme.

Join us again soon for more

trending topics and related vocabulary here

at 6 Minute English.

Goodbye for now!

Bye!