Ep49: Johan Rockström

“I think this is one of the most fundamental issues…” Johan Rockström on tipping points and planetary boundaries.


In this episode of Cleaning Up, Michael Liebreich talks to Professor Johan Rockström, Director of the Potsdam Institute for Climate Impact Research.

Johan argues discusses his Netflix documentary, Breaking Boundaries, which he made with David Attenborough, that investigates biodiversity collapse and the pressures of climate change. The conversation then moves to a discussion on planetary boundaries and the plausibility of RCP 8.5, a scenario used by scientists to predict the consequences of climate change.

This is an abridged transcript of the conversation, edited for clarity.


Michael Liebreich:  Johan, welcome to Cleaning Up. Tell us a little bit about the documentary Breaking Boundaries that has been released on Netflix. What does it try to do?


Johan Rockström: The working title of the documentary before Netflix came up with this great new title was The Best Untold Story in Town. And I think that says a something because it tries to tell the story of how we, as humanity, now impact the entire planet and determine its outcome. We're sitting in the driving seat, and how we navigate the Anthropocene, the new geological epoch we're in, to avoid crossing tipping points, but at the same time, transitioning in this exponential journey back to a safe operating space within planetary boundaries.


ML: You set this up with this one extraordinary chart, this very long-term temperature chart, which shows how unusual the last 8,000 to 12,000 years has been in terms of stability.


JR: The Planetary Boundary Framework, which is at the heart of the Breaking Boundaries documentary, emerges from 30 years of extraordinary scientific advancement. It's the advancement from ice core science, showing how the planet has been oscillating over the past 1 million years in and out of deep ice ages for 400,000 years, and then into shorter 15,000 yearlong integrations, and back into ice ages.

We have six to eight such cycles the last one million years, they follow a very predictable cycle called the Milankovitch cycles, which have been determined by the orbit of planet Earth around the Sun. We Homo Sapiens, we modern humans, have only been on planet earth for roughly the two final cycles, or the last 200,000 years. We've been hunters and gatherers and a few million people during basically the entirety of that period.

At that point we shift from being hunters and gatherers to inventing agriculture and we start the civilizational journey as we know it. We have significant scientific evidence today that shows that, thanks to the stability, we were able to shift from hunters and gatherers to farmers, and develop civilizations, meaning that our modern world depends on the Holocene, which is the geological epoch before what we now call the Anthropocene. That insight is a key entry point towards then defining what it takes to keep the planet there. And there you have the planetary boundary framework in a nutshell.


ML:  This is fundamental to your quest, which is to find the edges of the room but not to touch them. And so, you're looking for these boundaries and looking for early warnings on the boundaries. But inherently, we don't know where those boundaries really are. It has shifted in the last three or four years since Paris and since the IPCC 1.5 degrees report. Now, the orthodoxy is that 1.5 degrees is the tipping point. But we don't really know, do we?


JR: To begin with, I think there are very few scientists, and I'm not among them, suggesting that 1.5 degrees above pre-industrial temperatures is a tipping point threshold. Most science exploring the risk of tipping points, which are when a system like the Greenland ice sheet, or the Amazon rainforest, or the overturning of heat in the North Atlantic, shifts from one set of feedbacks that keeps that in the state today and it crosses a tipping point, and the feedback changes direction, and it's self-enforced in a new direction. Rain forest shifts over to a savannah state, for example.

Now, the science today shows that if we reach two degrees, we are at risk of triggering tipping points. Not that the planet would tip but we are triggering a significant number of tipping points at 1.5, it's rather that the mainstream of science is that we will feel big impacts, we will have a lot of damage. Damage in terms of disease, heat waves, floods, droughts, invasive species, sea level rise. All the difficult to handle impacts will start to occur. There is science to show that three tipping points may be at risk already at 1.5.  

But I would say that 1.5 remains a kind of a high impact point, hitting the low-lying island states and low coastal zones of Bangladesh and an increasing heatwaves around the world at two degrees, even though we do not know for certain, but past two degrees and we see more and more indication that there might be points where some of these tipping points, the big ones like the Amazon rainforest, or the Atlantic, or the larger parts of Greenland, may cross tipping points.


ML: I have weighed into this debate, on RCP 8.5 as I am frustrated with people confusing commitment time, the amount of time it takes to push the ball to the top of the hill before it starts to roll down the other side, with the amount of time that it might spend rolling down the other side and causing the most catastrophic harms.


JR: I think this is one of the most, perhaps the most, fundamental issues to resolve because not only is this misconception out in society, but all economics has failed here. It can only focus on impact time, all the discount rates, everything is just focused on when you lose your capital, in terms of impact commitment, time, and nobody puts any price on that. And I think that's one of our biggest failures. That's why you have the youth rising. Fridays for Future is about feeling this being unacceptable, that we commit all future generations to a planet that will be in a worse state.


ML: You’ve said in the past that you are, in some sense, optimistic. What is causing you to be optimistic now?


JR: In my whole professional career there's never been a reason to be more concerned based on the evidence we have today. But I've never in my adult life had more reason for optimism than today. Why? One reason is that we're starting to see so much evidence that sustainable solutions are scalable, and they give better outcomes. So, we're starting to see market parity on renewable energy systems with coal fired plants. We're starting to see evidence that the health outcomes are magnifying the benefits of renewable energy systems. We're starting to understand that building resilience in societies and avoiding future pandemics is related to nature and sustainability. So, is rapidly changing face towards being both economically more attractive and as a pathway towards security, stability, and health resilience. So instead of being what you and I have been experiencing for four decades, an environmental agenda and about protecting and about keeping humans away, and about the willingness to pay, it is now more and more an agenda of competitiveness, it is really a race to zero on climate.