- With all the bad and often terrifying news
about climate change, doomsday may seem
like it's just around the corner.
But is it?
There are electric cars, solar panels,
and wind turbines everywhere.
Still, we've wasted a lot of time arguing
over if and why global warming is even real,
let alone a priority.
So how are we doing?
Well, in the early 2010s, a set of emissions scenarios
called RCPs ranging from very stringent climate policy
to no climate policy at all was developed
to represent what warming could look like by 2100.
To get an idea of how we're doing,
we asked experts in the field which one of these scenarios
looks most likely today.
These scenarios were developed in the wake
of the global financial crisis, when emissions dropped
for the first time in the history
of many developed countries, but by 2010,
they had begun to rebound along with the economy,
and developing countries with enormous populations
like China and India were planning massive investment
coal plants to power economic growth
for billions of people.
- If you had asked me 10 years ago
whether I thought we would be in the place
we are today, I would've thought that it would've been
very unlikely, I would've thought
that there's no way that that's possible.
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- So where are we today?
And where are we going?
The RCP origin story can help us understand.
- Back in the lead up to the IPCC fifth assessment report
that came out in 2013, the energy modeling community
developed four pathways, which were essentially
four different possible warming outcomes
at the end of the century.
- Now the Representative Concentration Pathways
all come with a number, for example RCP 2.6,
RCP 4.5, or RCP 8.5.
That number is essentially the imbalance
in earth's energy budget resulting from human influence
on climate, and that number is expressed
in watts per meter squared.
- So in the case of RCP 8.5, this means
that humans would have emitted enough greenhouse gases
into the atmosphere to add an additional 8.5 watts
per meter squared of solar radiation to the climate by 2100.
And considering how many square meters
are on earth's surface, that's a lot of watts.
This many, to be exact.
Each of the RCP levels projects an estimated average
of global warming.
RCP 8.5 is close to five degrees,
RCP 4.5 is just below three degrees,
and RCP 2.6 represents the Paris Agreement goal
of limiting warming to well below two degrees.
RCP 8.5 with its associated five degrees of warming
is truly an apocalyptic scenario.
It means game over, an existential threat.
It models a world with no climate policy,
and it's hard to argue that we had or have
an effective climate policy
either domestically or internationally.
- Because RCP 8.5 was the only one of the RCPs run
with no climate policy, a lot of people
started referring to it as business as usual,
or in a world without climate policy,
we'll have, you know, five degrees of warming.
- Emissions were just increasing year after year after year.
There was the Kyoto Protocol in 1992,
and it was widely considered to have been a failure.
It really seemed feasible that we could end up
on a pathway where coal use would continue to expand,
where we would continue to prioritize
sort of fossil fuel economic growth
throughout the remainder of the century.
- And a real problem seemed to emerge
with reducing emissions.
So far in the 20th century, increasing carbon emissions
had been correlated with increasing gross domestic product,
and even reducing poverty.
China's emissions were growing very fast
along with their economy, and even with all the problems
associated with rapid development,
they were lifting citizens out of poverty.
Other developing nations hoped to follow their lead,
and coal was the fuel of choice.
Could the developed world, comparatively rich
after more than a century of burning fossil fuels,
really ask them to give up on coal?
And that's when something very important changed.
In the 2008 global financial crisis,
the emissions of many developed countries
did what they had always done, they followed the economy,
downward this time.
But then, economies rebounded.
After a brief uptick, the emissions
of large carbon polluters like the US, EU,
and Japan surprisingly continued to fall,
even in a world with no functioning climate policy.
And GDP continued to rise.
- We're not in "business as usual" anymore,
or at least "business as usual" has changed.
- So what exactly changed? And should we still
call RCP 8.5 "business as usual?"
- You know, RCP 8.5 is very much a world
dominated by coal.
By 2100, global coal use has increased sixfold
above 2010 levels, and global emissions have tripled.
In the real world, global coal use has been flat,
if not slightly declining since 2014.
You know, clean energy costs have fallen dramatically,
solar is 90% cheaper in the last decade.
Wind is 66% cheaper, batteries are 90% cheaper,
you know, electric vehicles are about 14%
of new vehicle sales globally now,
and upwards of 20% in places like China and Europe,
and so you know, we're having an energy transition
that was not accounted for in these sort of
worst-case scenarios a decade ago.
- Seaver described this transition
as one where activists, advocates,
and even scientists push for emission reductions.
No one got exactly what they wanted,
but there was just enough government
and society support to create a tailwind
for innovators, even while the U.S. was busy
pulling out of international agreements.
- You can't really just disentangle sort of state policies
from real acceleration in private sector clean energy.
It was actually because of early subsidy programs
in Japan, in Germany, and in China in particular,
that really helped fill in the gap
between what was economically feasible
and sort of what needed to happen.
- This is all extremely good news,
and we're no longer in a no climate policy world,
at least not entirely.
In 2015, the Paris Agreement was signed,
creating voluntary benchmarks for countries to meet
in order to stay well below two degrees of warming,
or RCP 2.6.
However, almost no countries are actually on target
to meet their benchmarks, and the four largest emitters
have a long way to go to even get close,
so at this point, RCP 2.6 is also not very likely.
- And so that's the reason why we think now
that the world is probably headed toward a bit
under three degrees under current policies
and sort of technological developments,
rather than you know, close to five degrees,
where some people thought we were headed.
- But even if two degrees of warming
is still hugely ambitious, isn't it cause for celebration
that we've come so far from the old projections
of five degrees?
- You know, it's probably not literally
the end of the world, I think humanity could survive
in a world of three degrees, but it's not a world
we want to leave to our children.
- You know, the IPCC was very clear,
saying that every little increment of global warming
is gonna make things more difficult to face,
come more frequent heat waves, worse floods,
more intense hurricanes, more prolonged droughts.
- We've already warmed 1.1 degrees,
so we're talking about almost three times
what we're experiencing today.
- If you think about being a young person at 40
and how it's gonna be at 80, I feel like it's similar
to a world where everything is getting
a little more difficult, a little worse,
and all the risks are increasing of,
you know, catastrophic outcome.
- And the list of impacts goes on and on... and on.
But perhaps the most important reason
to curb emissions is not just to stop warming,
but to slow it down.
- So a scenario like RCP 8.5 warms quickly,
and therefore, doesn't leave us enough time
or challenges our adaptation by changing
the climate not only a lot, but fast.
And a scenario that limits warming at two degrees
is not only beneficial because of that sheer point,
but also because by definition, it's going
to do that slowly, and therefore, letting society
but also importantly the natural ecosystems adapt.
- At the current rate of warming, human adaptation
has actually been working out pretty well so far.
In fact, according to WMO, over the last 50 years,
the number of disasters globally has increased
by around 400%, while the number of deaths
has fallen by two thirds.
- Right now, rich countries could potentially
adapt to these changes, poorer countries
will have a lot harder time doing so,
and there may well be a world where we don't do
a great job of solving poverty or some
of these other challenges that face humanity today.
And so to have that world with climate change
on top of it could potentially be catastrophic
for a lot of societies.
And so yeah, I'd like to hope for a world
where we all become rich and equal and high tech
and can deal with three degrees of warming,
but I don't want to bet on it, and I don't want
to bet the future of humanity on it.
- And our current trajectory of RCP 4.5 looks likely
to trigger some of the tipping elements
we discussed in an earlier episode.
So limiting warming to under two degrees, RCP 2.6,
or even RCP 1.9, is a new target
for avoiding the worst impacts of climate change,
and this will require getting all global emissions
down to zero in just the next 50 years or sooner.
- You know, right now we are dealing with the easier parts
of the economy to decarbonize.
So you know, I'm, I think it's gonna be a heavy lift.
So we're not just talking about emissions
in the U.S. and Europe, we're also talking
about China, we're talking about sub-Saharan Africa,
which is a huge amount of you know,
development and growth expected over the next century
and needed over the next century,
and we're talking about, you know,
all the different players in the world
aligning on these sort of goals.
The good news is that we've started to see
more commitments by countries to do just that.
So as of 2022, about 75% of global emissions
are covered by countries that have committed,
at least on paper, to get to net zero emissions
by the middle to late 21st century,
and that includes countries like China and India,
Japan, South Korea, Brazil, as well as of course,
the U.S., the EU, and others.
- While we have solutions for things like decarbonizing
the electricity system or the transportation system,
there are large, unsolved challenges in areas
like heavy industry and shipping and aircraft.
- But I'll be honest, what I take from this episode
are two things.
First is the fact that humanity created
a reality of goals that felt like a fantasy
just a few years ago.
As just one example, in 2006, a documentary
called "Who Killed the Electric Car"
detailed all the government and industry resistance
to electric vehicles.
Now, the U.S. government will pay you
thousands of dollars to buy one,
and they're everywhere.
And second, the reason this remarkable progress
was able to occur was because people fought for it.
- I think the fact that we've already made
so much progress in the last decade
toward bending down the curve of future emissions,
should be a hopeful sign.
It's evidence that we can actually solve this problem
if we collectively get our act together.
At the same time, we can't be blindly optimistic.
We can't assume the technology is gonna solve
all our problems, we can't assume that the problem
is gonna solve itself, we need concerted action
by governments, we need policy,
and we need people to get involved in pushing that,
'cause we're not heading toward a world
we want to leave future generations right now.
We might not be heading towards the literal apocalypse
anymore, but we're still heading
toward a pretty bad outcome, and we can do much better.
- And now it's time to hear what you think.
Are we too alarmist, or not alarmed enough?
Considering how far we've come in the last decade,
is it possible we can shift business as usual again,
this time, from RCP 4.5 to RCP 2.6,
and keep global warming under two degrees
and a planet we all want to live on?
You're watching "Weathered," so you're probably passionate
about fighting climate change.
You might also be interested in The Earthshot Prize.
Created by Prince William, The Earthshot Prize
aims to spotlight and fund groundbreaking solutions
to the world's most urgent environmental challenges.
Check out The Earthshot Prize over
on the PBS YouTube Channel, and get to know
the amazing scientists who were awarded
more than $1 million each.
The link is in the description below.
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