All language subtitles for Can We Cool the Planet¿ ¦ Full Documentary I NOVA ¦ PBS

[Music]

our rising temperatures driving earth's

ecosystems

past a point of no return we can't go

back there is no path backwards

every year the damages are worse

we have promising technologies that put

solutions within our grasp

but are we reaching far enough we have

to have

emissions cut to zero even if we stop

emitting co2 we still have the co2 we've

already admitted

so scientists are building a new toolkit

it has power

to ensure a prosperous future our

society has to survive

we need to reduce the heating effect

cutting edge solutions it's going to be

revolutionary

it's like science fiction there's the

balloon up there

and high risk measures i really hope

we'll never have to do this

it's really important that humanity has

a backstop

in a race to discover can we call the

planet

right now on nova

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it's a new time in the earth's history

in which we're not just inhabiting our

planet

we're operating as stewards of the very

thing that we're living on

since the industrial revolution humanity

has been running an

unintentional experiment in earth's

atmosphere

pushing the climate to new extremes

things are going to get

hot well you can

attitudes have changed rapidly because

everyone can see for themselves

the climate change that is occurring a

child born today

will witness across her lifetime a

planet transformed by rising temperature

[Music]

how did we get here

every time you get in your car every

time you fly a plane

every time you turn the heat on all of

those things are putting

carbon dioxide into the atmosphere and

if there's more carbon dioxide in the

atmosphere

there's a higher temperature and now

temperatures have started to spike

if we keep pumping billions of tons of

co2 into the atmosphere each year

we really will cook ourselves literally

in the end

to stop the worst impacts of planetary

heating we need rapid emissions cuts

starting now the

developed nations of the world need to

go from the energy system

they have now to one that emits nothing

zero in 30 years time

the good news is we know how to do that

renewables now are the cheapest form of

electricity on two-thirds of the earth's

surface and it's going to be everywhere

a world of carbon-free energy is coming

but climate impacts are coming faster

lasers are at power there it is

so scientists are opening a second front

in the battle

suite it has power bringing new

technologies to bear on the way we fight

climate change

we now have so much data this is going

to be the game changer

there are a whole class of solutions to

actually get this job

all the way done by removing co2

from the air this little guy this is

just the beginning

converting co2 from a waste to a

resource

we see this kind of as a testing ground

even extreme measures like shielding us

from the sun there's been a technical

revolution

in the last few years that's unlike

anything we've seen

in the previous hundred

this is a problem with a solution

can a new wave of climate tech take us

the rest of the way

to turn down the global thermostat

we need to look at everything that's out

there natural solutions

co2 sequestration solar geoengineering

there may be this idea out there that

nobody has come up with it that could be

really transformative

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cooling the planet means first stopping

more co2 from entering the

atmosphere and then finding ways to

remove it

but just how much co2 are we talking

about

imagine you filled the national mall

all the way from the lincoln memorial to

the capitol steps

with coal

and you piled it up all the way to the

top of the washington monument

10 times

that would be a gigaton of coal

giga means billion so that's a billion

tons

now we actually burn 10 times that much

carbon every year

people actually go dig that stuff up out

of the ground 10

billion tons of it and set it on fire

in power plants in engines in factories

all over the world

and then because that carbon is reacted

with oxygen 10 gigatons of carbon is

burned

but it creates 37 gigatons of co2

at our current rate that's just one year

of co2 emissions

to blunt the impacts of heating the

planet we need to shrink that number

to zero

but there's another problem

the gigatons that came before the single

most important fact about climate change

is that the carbon dioxide that we emit

into the atmosphere

stays there for thousands of years

year after year we live with the carbon

dioxide we've added over time

nearly 1 000 metric gigatons since the

industrial revolution began

almost everything we emit stays there

that's staying there until you do

something about taking it out

pulling co2 out of the air

it sounds futuristic but it's a problem

we've encountered before

remember apollo 13. it was all about co2

filtering right that's that was the big

problem how to get the co2 out of the

air

in 1970 following an accident the crew

of apollo 13

aborted a mission to land on the moon

forced to return to earth in a smaller

capsule

the astronauts faced a big problem

you're in confined spaces people exhale

co2 you need to remove that co2

every exhale caused carbon dioxide to

build up

making the air increasingly toxic okay

now let's everybody keep cool

let's solve the problem but let's not

make it any worse by

guessing the astronauts survived

by modifying their air scrubber to

remove more carbon dioxide

inside the scrubber negatively charged

sites on the filter

polarize and bond with the co2 removing

it from the air

could something like this work in

earth's atmosphere

there's not a lot of co2 in the air

compared to nitrogen oxygen

imagine a box with 10 000 ping-pong

balls in it

and four of them are painted black those

are the co2 molecules

trying to find those four balls out of

that big box full of ping pong balls

is hard

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removing co2 from a spacecraft is one

thing

removing it from our atmosphere poses a

much bigger challenge

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is it realistic most people

to whom we told we are taking co2 out of

the air would say you're crazy

but here you see a full-scale direct air

capture plant

you see it consists of 12 individual

modules capturing the co2 out of the air

jan wurtzbacher is a co-founder of climb

works

a swiss startup specializing in what's

called

direct air capture

to this side we suck in ambient air with

400 ppm that's

400 parts per million co2

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and on the other side we expel about 100

ppm

co2 content so three quarters are kept

inside

a filter with highly reactive chemicals

called amines

catches even small concentrations of co2

heating the filter then breaks the bond

you release the co2 and you can extract

pure

concentrated co2 and then you start all

over again

but generating the energy to do this can

produce its own

co2

their solution for that is garbage

here we are on top of the waste

incineration plant the reason why we're

here is

the main energy source for a process of

co2 capture from the air

waste heat from the incineration process

heat that would have been wasted instead

heats the filters inside the array

which capture nearly 1500 metric tons of

pure co2 a year

about what's expelled from the tailpipes

of 300 cars

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once you've pulled co2 out of the

atmosphere with a direct air capture

machine

the question is what to do with it the

big picture

is taking one percent of co2 out of the

atmosphere within the next five to ten

years

that is roughly 400 million tons

and store it underground

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could we put carbon right back where we

found it

underground there are lots of rocks near

the surface of the earth

that would want to bond spontaneously

with co2

there's enough of these kinds of

minerals that you could remove

all of the atmospheric co2 many many

times over

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one of the best places to try that out

is iceland

here we are the land of ice and fire

we have eruptions we have earthquakes

iceland is an island formed out of

volcanic rock

called basalt we see the bustles like

mountains

here around me and actually extending

several kilometers downwards

basalt is porous rock that readily bonds

with co2

over centuries

sandra schneiber's daughter's team has

found a way

to speed up that process carpex is the

method

of capturing co2 and turning it

into stone

magic but it's magic that already occurs

in nature

carb fix is turning one third of the co2

from this power plant

into solid rock in less than two years

the key is water

inside this scrubber gaseous co2 is

dissolved in water to react with basalt

more quickly

this crop is actually just a giant soda

stream

the fizzy water is then pumped into

injection wells

this is actually my favorite part of it

all

from here the magic starts to happen

this pipe extends to over 2000 feet

and there we finally release this

fluid to the rock

once inside the basalt the dissolved co2

reacts with metals in the rock to form

new solid minerals

like calcium carbonate once we have

injected the co2 into the rock it's

there forever

and sandra is looking beyond iceland

she's test driving a direct air capture

unit

that can suck up co2

we don't need a power plant this can be

done anywhere where you have

a formation to store your co2

what that means is you can go backwards

you can reverse the process

of emitting carbon dioxide into the air

negative emissions technologies like

direct air capture

could play a role in reaching net zero

the moment when humans remove as much

co2 from the atmosphere

as they put in so why isn't this

the ultimate answer to our co2 problem

these technologies are very hard to

scale up to a meaningful amount

the base module of our direct air

capture plant that's a 40 foot shipping

container

in order to take one percent of global

emissions out of the air

we would need 750 000 shipping

containers

all to remove just half a gigaton of our

annual emissions

direct air capture is very expensive

and it takes energy to suck co2 out of

the air

so i hope you're not imagining direct

air capture vacuuming up the entire

fossil fuel emissions of the world

because that ain't gonna happen

we'll need lower cost clean energy

everywhere before the promise of direct

air capture

can meet the scale of the problem

themselves so some are exploring

another idea recycling our emissions

correction factor 0.7

we need to think about this problem very

pragmatically

we can electrify a lot of things but

there's certain parts of the energy

system that are extremely hard to

decarbonize

a good example is aviation

you couldn't build today a commercial

airplane

for long distances which could fly on

batteries you would just

carry way too much weight

this is physically impossible there is

no way around jet fuel

we need to be producing fuel that when

you burn that fuel doesn't emit carbon

dioxide

remove go ahead and rotate aldo

steinfeld

thinks he's found a way

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perfect we are on target

we have demonstrated that we can produce

liquid hydrocarbon fuels

from two ingredients

sunlight

and ambient there

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it may sound like science fiction or

magic

but it is chemistry is heat transfer

and also it's a lot of engineering

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aldo captures co2 and water from the air

and feeds them into a solar reactor

solar radiation is reflected and

concentrated at the focus by a factor of

5000

it is like the intensity of 5 000 suns

concentrated solar energy drives a

reaction

that generates a synthetic gas which can

then be

converted into fuels and here in my

hands

i have an example of solar methanol

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when it's burned the carbon in this fuel

returns to the atmosphere

but since it was harvested there the net

co2

is zero this is called carbon neutral

and hundreds of scientists like aldo are

working to make carbon neutral fuels a

reality

if they succeed annual net emissions

could drop by as much as 1 billion

tons it's going to be

something revolutionary

but with these fuels up to six times the

cost of standard fuel

it's a revolution that has only just

begun

but it raises the question what else can

we make by recycling co2

carbon is this incredible building block

think of it like those little sort of

lego toys that we used to have only

there's four

little plug-ins for it so you could bond

carbon to carbon to carbon to carbon to

build

all kinds of stuff imagine a world where

everything around you is made from

carbon emissions

from the products you use every day to

the clothes you wear

this ad from the xprize foundation

pitches a future where recycled co2

shapes our world and a 20 million dollar

bounty to make that a reality

we announced hey there's a 20 million

dollar prize out there we're looking for

innovators around the world

if you know how to convert co2 into a

useful material consider entering this

price

we are trying to help catalyze the whole

ecosystem of companies of investors of

people that can deploy these

technologies

the carbon x prize has brought five of

the finalists

here to put their innovations to the

test

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they're setting up shop next to a

plentiful supply of co2

they've got to take the emissions from a

natural gas power plant and convert

those into

whatever material they like from

toothpaste

to yoga mats to watches

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each team will be scored on its net co2

reduction

you could have a process that uses up a

lot of co2 to make its product

but in the end just produces more co2

than it uses up okay we don't want that

yep we want things that actually are

reducing co2 overall

we just moved to site about two weeks

ago a day later and i think we'd have

snow in here that would be shelling out

a so sinha is the ceo of carbon

upcycling technologies

or cut we're a carbon tech company

which takes carbon emissions and

converts them into solid nanomaterial

products

for use in anything from cutlery to car

parts

but to make the biggest impact on co2

and win this competition

kapoor is focused on cement

cement is an essential component of

concrete

the glue that binds it together

but producing it creates a lot of co2

cement production accounts for over

eight percent of the world's annual

emissions

if all the cement producing companies

were a country they would be the third

largest

emitter in the world

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the porv's process converts co2 into a

needed ingredient for

concrete and he believes it will also

reduce the amount of cement that

concrete manufacturers need

he starts with an industrial waste

powder left over from burning coal

called fly ash with the reactor that we

have behind us

we're scaling up and commercializing an

enhanced fly ash

where the fly ash has been chemically

activated to capture co2

as the reactor spins the fly ash we

inject co2

ball bearings coated with a catalyst

speed up the chemical reaction

as the ball bearings rise and fall the

motion breaks up the fly ash

and roughs up the surface so that more

co2 can be absorbed

as the co2 penetrates the fly ash

surface

it forges tunnels along the way in

effect

carbon dioxide has bonded with fly ash

to create a nanoparticle with more

reactive surface area

which combine concrete together and

strengthen it

with less cement if concrete producers

are able to use less cement

in their production they could

considerably reduce the emissions that

come from their industry

the question remains is it strong enough

for concrete makers to buy it we just

want to make sure that the technology is

good and that it works really well

one of our local partners is a

family-owned calgary-based

concrete business called burnco

burnco is testing the strength of

concrete held together

using a porv's nanoparticle

when the cylinder breaks we will have

our final pressure

read up there

these are impressive results in normal

production you're

looking for changes of three to four

percent and these are showing

results in in double digits it's very

encouraging

we're very confident that we can get up

to a 10 reduction in the

amount of cement used today but our real

target is to get that number up to 20 or

25

then we start talking about

significantly moving the needle on the

37 gigaton a year number

but even if these new technologies can

scale to their full potential

they could only lock away a fraction of

our emissions

the total volume of co2 that we create

in the atmosphere is so much bigger than

the volume of

any product i think people are losing

track

of the central issue which is we have to

reduce net co2 emissions

easiest thing believe it or not is to

burn less carbon right to not

generate the co2 in the first place

carbon-free energy like wind solar

and nuclear power can drive down most of

our annual emissions

and the rest could be offset with

negative emissions technologies

that remove co2 from the air

we will do it we will get to the day

without a global celebrations

we get to net zero day we brought human

co2 emissions to zero i think it'll

happen in my lifetime it is doable

but on that day we have not solved the

climate problem

all we've done is stop making it worse

the problem that remains is

heat

the temperature of the earth is

determined by heat coming in from the

sun and heat going out by radiation out

to space

every single day co2 from our past

emissions

traps energy in the earth's system the

same amount of energy as

500 000 of the bomb dropped on hiroshima

detonating at once that heat

is altering our climate what's it going

to be like when

you know three months of the year 115

degrees

when vast ecosystems have died out

people are going to push for for doing

something about this

and many fear earth is approaching a

tipping point

that will trigger rapid change

the uncertainties that keep me up at

night

are what if we aren't doing enough and

there's some

monster lurking behind the door that all

of a sudden

comes out into the world among us

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it's a good idea that humanity has some

sort of a backstop technology

something to do if we get surprised in a

way that is very very dangerous

some think that backstop could be solar

geoengineering

it's a way to intercept sunlight coming

into the planet

to cool the planet

the core idea is that humans might

deliberately alter

the earth's energy balance to compensate

for

some of the warming and climate changes

that come from greenhouse gases

geo-engineering the climate is a

controversial idea

but nature can show us examples of where

we might start

clouds the cloud is just water

that's condensed down onto particles

into small droplets these collections of

droplets

are in effect floating sun reflectors

clouds play a huge role in controlling

the climate because they control the

reflectivity of the planet

especially over the ocean you go from

sunlight hitting a very dark surface

where a lot of the sunlight is absorbed

to sunlight hitting

extremely bright surface reflecting a

lot of that sunlight back to space

sarah dougherty of the marine cloud

brightening project

is working on a way to boost that effect

can we add really small sea salt

particles to clouds

in a way that significantly increases

their brightness

and do so over enough of the ocean that

we would have

a significant impact on the global

temperature

but how do you make salt water particles

and launch them up into clouds

what we need is a nozzle like you'd see

in a sort of a snow blower

except the particles that we want to

produce are about a thousandth the width

of a human hair

so sarah's working with an engineer who

knows all about machines for spraying

super fine droplets a concept developer

of the earliest inkjet printers

in a different life i was an engineer

and a

physicist i

i couldn't enjoy retirement anymore and

just sit there watch what's going on

once you know what's going to happen or

might happen

you can't sit down and say yeah i'm just

gonna enjoy life

armand and his team of retired

scientists

have been developing a cloud brightening

machine for over 10 years

they have been self-funding this

research in borrowed lab space

park is a really good place for them

because of our history with aerosols

park or palo alto research center

has infused the marine cloud brightening

project with fresh expertise

and cutting-edge tools here

kate murphy can make aerosols from just

about anything

this is our deep conditioner aerosols

are tiny particles suspended in air

this is ketchup

for clouds they're not going to spray

ketchup

but kate can help the team design a

nozzle for spraying salt water

let me just give it a little water okay

okay

kate's expertise will help optimize the

size and speed of the particles

to propel them into marine clouds

so you're going to be redesigning the

nozzle based on your computational fluid

dynamics well we hope to be able to

understand the effect of multiple

nozzles

so we would want to measure things like

velocity and direction

these crisscross laser beams can help

reveal whether our mons nozzle will hit

the mark

the lasers are at power um it looks like

our signal is pretty good

so can you measure the vertical velocity

do you have a measurement of that that

would be of great interest to us

park will be working on developing a

full spray system

and then we would want to move outside

into real atmospheric conditions

on the other side of the world outdoor

research has already begun

armand and the team have shared their

insights with researchers in australia

who are testing cloud brightening as a

way to cool the waters surrounding the

threatened coral of the reef

that project is targeted and local

but some estimate that cloud brightening

on a global scale

could offset all the heat trapped by our

co2 emissions

it will probably take a good 15 to 20

years to do

all of the research involved with

understanding how big of an effect

we could have by brightening clouds and

also what all of the side

effects might be

those side effects are not well

understood and could include disruptions

to ecosystems and rainfall patterns

further research is needed we have kids

we have grandkids

we're doing it for their futures you

know and frankly

we are all in this together whether you

have kids or not

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we're more than individuals our society

has to survive

[Music]

we're facing a problem that's getting

worse not

better do we need to consider

more extreme measures

in 15 years or 20 years humanity may

find itself at a point where impacts are

so big that there's a very large demand

for

fast action to prepare

frank is starting now

by researching a controversial

technology that goes

further than brightening clouds it would

brighten

the entire planet

putting particles in the stratosphere

could reflect back some sunlight to

space

reducing the amount of sunlight that

hits the surface and cooling down the

planet

the effect would be immediate

we know this works because every time a

big volcano goes off and it injects

aerosols into the stratosphere

the planet cools down

that's the idea behind solution

engineering it's like

drawing a curtain over the face of the

earth

the first time you hear about this you

think well that sounds like a really bad

idea

how could that not go wrong

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but what we're doing to climate as

humans that really

to me starts seeming also

quite scary and crazy and

really worrying the fact is the co2 is

in the atmosphere

without a time machine we can't make it

go away

we want to in the long run do carbon

removal

but during the time that concentrations

are high

we might want to do solar geo sharing to

reduce the climate risk

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all that is hard mounted to us yes

that is exactly what i want and then

there's the balloon up there

frank and david's team is designing a

first of its kind experiment

called scopex to investigate the impacts

of solar geoengineering

the only place i see that conversation

getting sticky is where we

do risk assessment on it if you put

these particles out

what happens when these come back down

what happens when it gets into the

environment

are we endangering people there are lots

of things that we might need to know

where the existing experimental

background is bad

you actually have to go out and make

measurements

the plan is to launch a 100-foot balloon

into the stratosphere and release a

plume of reflective aerosols

we want to put out the particles of

calcium carbonate for example

and then go back through this plume and

see whether the evolution of the air

is the way we predict it based on our

laboratory results

this is an experiment on a very small

scale

and in fact the amount of material we're

putting out is less than a normal

airplane flight puts out

scopex may be small but many fear

a large-scale manipulation of earth's

atmosphere

could trigger a cascade of dangerous

unintended consequences

that ripple across the planet nothing in

our scientific capability actually

enables us to understand the complexity

of the interactions

that would be set loose it's not just

that it lowers the temperature but what

are

some of the other effects on the

hydrologic cycle

or on heat waves and droughts

this is a manipulation of the earth's

atmosphere on a huge scale

what happens if things go wrong scopex

is designed to start answering those

questions

but there may be effects beyond the

physical that no experiment can predict

if we think that there's this solution

out there then people may

think it doesn't matter if you're

polluting the planet

the root of the concern is that solar

geometry and research however

well-intentioned will be used an excuse

for big fossil fuels to fight emissions

cuts

it's just like a sci-fi dystopian novel

or something where

we continue to just belch all this co2

into the atmosphere but hey it's okay

because we got these little umbrellas

that are you know hiding us from the sun

solar gma sharing does not get us out of

the ethical

and physical requirement to cut

emissions

but with so much uncertainty some think

we're better off investing

in a different kind of machine

one developed in nature's own laboratory

over millions of years

and with a proven record of safely

drawing down

gigatons of co2

[Music]

trees

i'm going on a hike through a forest i

have a tendency to look up

and say okay oh that tree's about 60

feet tall and then i try to calculate in

my head okay

how much carbon is stored in that tree

i think this is good lola fata jimbo

is a research scientist at nasa's

goddard space flight center

sweet it has power limit things work

she and her team are about to see these

century-old

trees in a new light green lights

there's carbon all around us if you

think of trees as a machine

then trees would be a carbon capture

machine

when we're looking at trees about half

of that

weight is carbon

lola and her team want to know how much

carbon is stored in this entire forest

to measure each and every tree they're

using

a special kind of tool

lasers we're using a terrestrial laser

scanner

that shoots out billions of laser pulses

every second

and then measures the distance from the

instrument to

whatever is around it

the data that we get back generated

point cloud

billions of data points form a 3d

measurement of forest volume

and the carbon stored within it's so

dense

that it almost looks like a photograph

it's like science fiction

this scan may look like reality but this

is

data

it reveals that in an area the size of a

football field

these trees are storing roughly 150 tons

of carbon

all pulled out of thin air

which prompts tom crowther to ask could

we

enlist trees in the race to draw down

co2

our lab is urgently trying to figure out

how we increase

the area of forest across the globe to

capture as much carbon as we possibly

can in the fight against climate change

tom's findings began with a surprising

discovery

we thought there was around 400 billion

trees on the planet

but we showed that there's in fact

around three

trillion trees

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there's more trees on the surface of our

planet than there are stars in the

galaxy

the big question is how many more trees

could we add

in order to understand the global forest

system we need to map a lot of things we

need to know where forests are where

forests could be

we collect our data from millions of

locations around the world where

scientists

have been on the ground evaluating those

ecosystems

data like leaf fall patterns in forests

around the world

i'm trying to understand the seasonal

rhythm of plants

microscopic organisms like the tiny

worms that feed the soil beneath the

trees

in just this clearing there's millions

and millions of nematodes living in the

soil

decades of satellite data on factors

like rainfall

and temperature when i look at

ecosystems most of the time i'm looking

from the top

down and with all of that data

we can start to see the patterns across

the globe

using remote sensing information from

satellites and

machine learning technologies we can

generate

maps that can predict which regions can

support new trees

and which ones cannot

this really is a data revolution

the detail is astonishing

and the potential for new forests is

vast

outside of urban and agricultural areas

there's room for about

2.5 billion acres of forest

the area we identified equals the size

of the united states

so there's a huge area available for

restoration

enough space for trillion new trees

all sucking co2 out of the air

if we were to restore a trillion trees

the right types of trees

in the right kinds of soils and have

them grow to full health

they could store an additional 205

gigatons of carbon

to put that into context we've released

nearly 660 gigatons of carbon

into earth's systems since human

industrial activity began

restoring global forests and conserving

the vital forest that we currently have

could take a huge chunk out of that

excess carbon this is a

really massive carbon drawdown solution

and we knew that this was going to make

an enormous flash

but these findings also made waves

that study is causing a lot of debate

on the one hand a lot of people are

talking about the potential of

restoration of force on the other hand

i would say um a lot of people are very

upset

about it

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the uncertainty around the amount of

carbon that's stored in trees

is so high that we can't really make any

informed recommendations on how many

trees we need to plant

lola wants to use new technology from

nasa

to fill those areas of uncertainty with

hard data

we have over 20 earth observing

satellites right now from nasa alone

looking at our planet earth but what

we're seeing is all

in two dimensions what we're missing

here is the third dimension

enter a powerful new tool called

jedi with the same laser technology used

in her terrestrial scanners

lola can get a three-dimensional measure

of forest carbon

from the international space station

jedi stands for the global ecosystem

dynamics investigation

which is what you're seeing right here

this is about the size

of a fridge you can see the lasers

shooting down out of the bottom of the

instrument towards the surface

of the planet we actually can see a full

profile of plant materials

the game changer here is that this is

going to be for the first time

a near global data set

jedi will give clearer insight on the

carbon new forests could store

but equally important it can pinpoint

the old forest carbon we must preserve

forests are really important for our

water supply forests protect

us from heat forests

breathe they breathe in some ways just

like we do

when you lose a lot of the ecosystem

services that forests provide

that has a direct impact on the

well-being

of people

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but on an increasingly populated planet

trees are not the only living things

competing for land

we already use all of our agricultural

land to feed our existing population

and over the next 30 years food demand

is going to double

if you take land to solve the climate

problem

you create another problem

so is there a solution that can solve

more than one problem at a time

some people are looking at ways in which

forests can help slow climate change

our research is somewhat different than

that we're looking at grasslands

i want to have enough so that we can do

experiments in california

wendy silver is looking for a way to

pull down

co2 right where we grow our food

earth's grasslands this is a

classic beautiful annual grassland

grasslands grow in places where there's

drought for part of the year

and these grasses have developed great

tools for getting water

particularly by growing more roots

and anytime plants invest a lot of their

energy

into roots it's like injecting carbon

into the soil

but tilling releases that carbon and

degrades the soil

and producing our food creates even more

problems

we all eat food every day we have to

grow that food

and we create a lot of organic waste in

the process

when organic waste sits in a landfill or

slurry pond

it creates an oxygen deprived

environment favorable to certain

microbes

which in turn produce methane a

greenhouse gas

34 times more potent than co2

we're trying to tackle three big

problems waste

degrading soil health and climate change

we came up with something relatively

simple

composting in composting

food waste is regularly turned adding

oxygen to the mix and keeping the

methane producing microbes at bay

it creates this organic and

nutrient-rich resource

like a slow-release fertilizer that

helps plants grow

by turning a waste into a nutrient

compost can boost plant growth and

potentially

turn vast stretches of earth's food

crops

into a carbon-storing juggernaut

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we now have 10 years of data showing

that

just a one-time dusting of compost onto

the soil surface

can have a long-term impact on plant

growth

and increase carbon storage and soils

wendy's research shows that a single

layer of compost

can increase plant growth by up to 78

and increase soil carbon by up to 37

percent

for three years the real challenge

is to extrapolate from little tiny soil

samples in the field

to big chunks of california or the globe

that's a huge challenge

as the hunt for solutions continues in

the decades ahead

stopping our emissions remains the most

urgent

challenge of today if we

really didn't do anything to limit

carbon emissions

we would have climate changes as big as

the changes from the glacial to

interglacial state and do that in

one human lifetime with huge potential

impacts

the more of a mess we make the bigger of

a mess we'll have to clean up

we today get to decide

whether to continue along this path

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or to dramatically shift our economy off

of coal oil and gas

every big transformative solution starts

small it starts with a couple people

talking

they make a small version they make a

bigger version more people pile in

this is one solution but we need

thousands of solutions if you want to

tackle climate change

there's no one magic silver bullet that

will solve this problem

the main challenge that we have is that

these transitions don't happen overnight

we have the tools already but we really

have to start moving

we need better transportation systems we

need solar power

and wind power and water power and

probably nuclear power

we need to plant trees we need to manage

our farms better

we need direct air capture i i think we

probably need it all

we have to start really looking at what

can scale up

and be maintained for decades if not

centuries

that's the challenge here but it's an

incredibly

important challenge

15 years ago no one would have predicted

that the emissions

in developed countries around the world

would be dropping

not fast enough yet but that gives me

hope and should give

everyone hope that with a combined might

of human ingenuity

we can actually solve this problem

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you