Transcriber: Translate TED
Reviewer: Rhonda Jacobs
(Beeps)
[Countdown]
(Clapboard claps)
Ten years is a long time
for us humans on earth.
Ten turns around the sun.
When I was on the TED stage a decade ago,
I talked about planetary boundaries
that keep our planet in a state
that allowed humanity to prosper.
The main point is that
once you transgress one,
the risks start multiplying.
The planetary boundaries
are all deeply connected,
but climate, alongside biodiversity,
are core boundaries.
They impact on all others.
Back then we really
thought we had more time.
The warning lights were on, absolutely,
but no unstoppable change
had been triggered.
Since my talk, we have increasing evidence
that we are rapidly moving away
from the safe operating
space for humanity on earth.
Climate has reached a global crisis point.
We have now had 10 years
of record-breaking climate extremes:
fires blaze in Australia,
Siberia, California and the Amazon,
floods in China, Bangladesh and India.
We're now enduring heat waves
across the entire northern hemisphere.
We risk crossing tipping points
that shift the planet
from being our best resilient friend,
dampening our impacts,
to start working against us,
amplifying the heat.
For the first time, we are forced
to consider the real risk
of destabilizing the entire planet.
Our children can see this.
They are walking out of school
to demand action,
looking with disbelief
at our inability to deviate away
from potentially catastrophic risks.
The next 10 years, to 2030,
must see the most profound transformation
the world has ever known.
This is our mission.
This is the countdown.
(Clock ticks)
When my scientific colleagues
summarized, about a decade ago,
for the first time,
the state of knowledge
on climate tipping points,
just one place had strong evidence
that it was on a serious downward spiral.
Arctic sea ice.
(Water sounds)
Other tipping points were long way off --
50 or 100 turns around the sun.
Just last year we revisited these systems,
and I got the shock of my career.
We are only a few decades away
from an Arctic without sea ice in summer.
In Siberia, permafrost
is now thawing at dramatic scales.
Greenland is losing
trillions of tons of ice
and may be approaching a tipping point.
The great forests of the North
are burning with plumes of smoke
the size of Europe.
The Atlantic ocean circulation is slowing.
The Amazon rainforest is weakening
and may start emitting carbon
within 15 years.
Half of the coral
of the Great Barrier Reef has died.
West Antarctica may have crossed
the tipping point already today.
And now, the most solid
of glaciers on earth, East Antarctica,
parts of it are becoming unstable.
Nine out of the 15 big biophysical systems
that regulate climate are now on the move,
showing worrying signs of decline
and potentially
approaching tipping points.
Tipping points bring three threats.
First, sea level rise.
We can already expect
up to one meter this century.
This will endanger the homes
of 200 million people.
But when we add the melting ice
from Antarctica and Greenland
into the equation,
this might lead to a two meter rise.
But it won't stop there,
it will keep on getting worse.
Second, if our carbon stores
like permafrost and forest
flip to belching carbon,
then this makes the job of stabilizing
temperatures so much harder.
And third, these systems
are all linked like dominoes:
If you cross one tipping point,
you lurch closer to others.
Let's stop for a moment
and look at where we are.
The foundation of our civilization
is a stable climate
and a rich diversity of life.
Everything, I mean everything,
is based on this.
Civilization has thrived
in a Goldilocks zone:
not too hot, not too cold.
This is what we have had for 10,000 years
since we left the last ice age.
Let's zoom out a little here.
Three million years --
temperatures have never broken through
the two degrees Celsius limit.
Earth has self-regulated
within a very narrow range
of plus two degrees
in a warm interglacial,
minus four degrees, deep ice age.
Now, we are following a path
that would take us
to a three to four degree world
in just three generations.
We would be rewinding the climate clock,
not one million, not two million,
but five to 10 million years.
We are drifting towards hot-house earth.
For each one degree rise,
one billion people will be forced
to live in conditions
that we today largely
consider uninhabitable.
This is not a climate emergency,
it is a planetary emergency.
My fear is not that Earth
will fall over a cliff
on the 1st of January, 2030.
My fear is that we press unstoppable
buttons in the Earth system.
What happens in the next 10 years
will likely determine the state
of the planet we hand over
for future generations.
Our children have every
reason to be alarmed.
We need to get serious
about stabilizing our planet.
Two frontiers will guide
this transformation.
The first one is in science.
Here's a new equation
for a sustainable planet:
planetary boundaries plus global commons
equals planetary stewardship.
We need to a safe corridor for humanity
to allow us all to become stewards
of the entire planet,
not to save the planet but to provide
a good future for all people.
And the second frontier is in society.
We need a new economic logic
based on well-being.
We are now in a position
to provide science-based targets
for all global commons for all companies
and cities in the world.
First task, we need to cut
global emissions by half by 2030
and reach net-zero by 2050 or sooner.
This means decarbonizing
the big systems that run our lives:
energy, industry, transport, buildings.
The fossil fuel era is over.
We need to transform agriculture
from a source of emissions
to a store of carbon,
and critically, we must
protect our oceans and land,
the natural ecosystems
that absorb half of our emissions.
The good news is, we can do this.
We have the knowledge.
We have the technology.
We know it makes social
and economic sense.
And when we succeed,
we can all take lungfuls of fresh air.
We will be saying hello
to healthy lifestyles
and resilient economies in livable cities.
We are all on this journey
around the sun together.
This is our only home.
This is our mission:
to protect our children's future.
Thank you.
(Lights click off)