The 55 Gigaton Challenge TED Countdown

Transcriber: Leslie Gauthier
Reviewer:

The air we breathe has changed.

The mix of gases is shifting,

with more and more greenhouse gases
like carbon dioxide.

And this shift is happening
faster each year.

In fact, concentrations of CO2
have reached levels

never before breathed by humans,

since Homo sapiens evolved.

In just a few hundred years,

eons of fossilized sunshine
have been burned as coal, oil and gas.

The exhaust has transformed
the entire atmosphere and ocean.

It’s like a pollution blanket,

and the result we know
as climate change.

So how much more of that fossilized
sunshine can we burn

before further destabilizing
the Earth’s systems?

Not much.

Think of it as a carbon budget.

We are currently adding 55 billion
metric tons of greenhouse gases

to the atmosphere every year.

This is the Gigaton Challenge.

By some estimates, at that pace,

we will have burned through
the remaining budget by 2030.

So to give us some room to breathe,

the world must reduce
greenhouse gas pollution

by more than seven percent each year,

every year of this decade …

starting now.

There are a number of ways to do that.

Let’s start by looking
at the greenhouse gases themselves.

CO2 makes up nearly 75 percent
of the pollution emitted each year.

There’s also nitrous oxide,

known as laughing gas,

but it’s no laughing matter,

seeping out of farm fields and elsewhere

and making up six percent of the problem.

And then there’s methane,

which you may also know of as natural gas.

It’s 17 percent of the total.

There are other greenhouse gases,

but these three make up the bulk
of the climate challenge.

All must be reduced –

and fast.

Methane is better
at trapping the Sun’s heat,

which means cutting methane pollution
is a necessary and fast-acting stimulus

for our carbon budget.

If methane emissions from agriculture

and the oil and gas industry
can be eliminated

in this decade,

we might be able to stave off catastrophes

like the loss of the Arctic sea ice
and glaciers all around the world.

CO2 has a longer life.

Once it is added to the atmosphere,

it can stay up there
for hundreds of years,

if not longer.

CO2 emissions
must be cut in half by 2030,

and then reduced even further by 2040,

to put the world on a path

of adding no CO2 to the air by 2050.

And that means transforming
the modern world as quickly as possible.

There are several ways to break down
the sources of greenhouse gas emissions.

Here we’re using the public
Climate Watch data.

Start with energy.

The majority of modern energy
comes from fossil fuels,

which makes the energy sector
76 percent of the climate challenge,

including the fuels
used for transportation,

industrial processes

and agricultural production.

The shift to clean energy
must be accelerated

by an order of magnitude

if we want any chance to restrain
global warming to 1.5 degrees Celsius.

And we’ll need more ways
to store this clean electricity,

whether that’s putting it
in the chemical bonds of a battery

or into a molecule of hydrogen.

Batteries and clean hydrogen
are also going to play a key role

in cleaning up transportation,

which accounts for 17 percent
of climate-changing pollution,

including the use of energy
to move people and goods around:

eight percent from cars;

five percent from trucks
and other heavy-duty vehicles;

and four percent
from shipping and aviation.

With abundant clean electricity,

the world can win the race
to electrify cars

and create cleaner
alternative fuels for trucks,

ships,

and even one day, airplanes.

Then there are our lifestyles

and the materials that make them possible.

That’s everything from the cement
and steel that go into buildings

to the plastic fibers in fashion.

All told, these materials account
for six percent of our emissions –

on top of the energy emissions
required to produce them.

And we’ll need new and clean ways
to make them or replace them.

Farming and animal raising
also have to change

as agriculture accounts for 12 percent
of greenhouse gas pollution.

That means everything
from how and what people eat

to how and what cows,
chickens and pigs eat.

It also means finding ways for farm fields
to go from sources of greenhouse gas

to places where
greenhouse gases get buried.

Agriculture is also the biggest
direct impact people have

on the plants, animals, microbes and fungi
that share this planet with us.

To truly solve the climate challenge,

the wild world will have to be
protected and restored

to allow all of life’s myriad
forms to flourish.

A halt in cutting down forests,

burning peatlands

and converting coastal wetlands

could prevent the release

of nearly five billion metric tons
of greenhouse gases each year.

Restoring nearly 200 million hectares
of degraded forestland,

peatland and wetlands

could also absorb almost
another four billion metric tons.

Perhaps even more importantly,

the ocean has vast potential
to help reduce greenhouse gases …

if we protect it.

Finally, there are technologies
being developed

to draw down CO2 from the atmosphere

because we have already emitted too much.

But very few of these machine forests
have been deployed

and they are too expensive
to scale up faster right now.

This is the climate challenge we face:

going from adding 55 billion metric tons
of greenhouse gases to the air each year,

to adding zero by 2050,

at the latest.

The countdown begins now.

(Music)

[Countdown]