-
(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 1 million, not 2 million,
-
but five to 10 million years.
-
We are drifting towards hot-house Earth.
-
For each one degree rise,
-
1 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)