Kind: captions
Language: en
[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
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
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