In this Frontiers Forum Deep Dive session on 18 January 2024, Sofia Palazzo Corner, Prof Martin Siegert and Prof Joeri Rogelj discussed the amount of temperature change we can expect after CO₂ emissions from human activities reach net zero, and how this can be built into climate models. They were joined for a panel and question and answer session by Ben Sanderson, Charlie Koven and Tessa Khan.
The session brought together the authors of the Frontiers in Science lead article ‘The Zero Emissions Commitment (ZEC) and climate stabilization’ in which they present the first comprehensive analysis of Earth processes controlling global temperatures and our knowledge gaps for each – plus a pioneering framework for building climate models that are better equipped to predict ZEC.
Links:
• View the Frontiers in Science lead article at: https://www.frontiersin.org/journals/science/articles/10.3389/fsci.2023.1170744/full
• View the Frontiers in Science article hub at: https://www.frontiersin.org/journals/science/article-hubs/global-warming-after-net-zero
Speakers:
• Sofia Palazzo Corner | Imperial College London, UK
• Prof Martin Siegert | University of Exeter, UK
• Joeri Rogelj | Imperial College London, UK
• Ben Sanderson | Center for International Climate Research (CICERO), Norway
• Charlie Koven | Lawrence Berkeley National Laboratory, USA
• Tessa Khan | Uplift UK
INTRODUCTION
00:00:00 Opening
00:00:30 Welcome & introduction | Gilbert De Gregorio | Head of Partnerships, Frontiers Planet Prize
00:04:39 Setting the scene | Prof Martin Siegert | University of Exeter
00:06:53 The Zero Emissions Commitment and climate stabilization | Sofia Palazzo Corner | Imperial College London
PANEL DISCUSSION
00:21:53 Introduction of panel session | Gilbert De Gregorio | Head of Partnerships, Frontiers Planet Prize
00:24:26 Panel discussion on what’s next after net zero? | Facilitated by Prof Martin Siegert | University of Exeter
Q&A SESSION
00:55:20 Audience Q&A session
CONCLUSION
01:23:08 Closing remarks from Joeri Rogelj | Imperial College London
Frontiers Forum Deep Dive sessions bring researchers, policy experts, and innovators together from around the world, to discuss a specific area of transformational science published in Frontiers’ flagship multidisciplinary journal, Frontiers in Science, and explore next steps for the field. Watch previous sessions at https://forum.frontiersin.org.
We see this paper as being part of a four-step process to improving our assessment of ZEC. The first is to identify the Earth system processes that drive this uncertainty and that’s what we’ve tried to do in our 26 levers. The second is to estimate their impact in different timescales and
The third is then to try and reduce this uncertainty through targeted research. And of course, the ultimate aim is to build models that can better give us an assessment of the Zero Emissions Commitment. Good morning, good afternoon and good evening, everyone,
And a very warm welcome to everyone joining us today for this Frontiers Forum Deep Dive session. Allow me to introduce myself. My name is Gilbert De Gregorio and I’m Head of Partnerships at the Frontiers Planet Prize and I’m absolutely delighted to be your host
And moderating today’s session that explores global warming after achieving net zero CO2. So, today’s Deep Dive session will be focusing on this lead article entitled “The Zero Emissions Commitment and climate stabilization” which was published last year on November the 14th and
It’s already been featured in both Bloomberg and the New Scientist right off the bat from COP28. I guess we can all agree that this is a very timely and topical theme that we’re very interested in learning more about. So, in their Frontiers in Science lead article
And its hub of complimentary content, which I invite everyone here to read, to explore, the authors, Palazzo Corner et al. present the first comprehensive analysis of Earth processes that control global temperatures and our knowledge gaps for each. Plus, and very interestingly, they introduce a pioneering new framework for building climate
Models that are better equipped to predict the expected additional change in global temperature once we reach and achieve net zero CO2 emissions. This approach is absolutely crucial for effective climate policies, as also discussed in the complementary publications that you can find in this hub. So, the article itself acts as a centerpiece
For a lot of great material including this editorial by Professor Michael Mann from the University of Pennsylvania; a scientific viewpoint article by Professor Damon Matthews of Concordia University; and a policy outlook by Brook Dambacher and Tessa Khan of Uplift UK, who we’ll hear from later today. There’s also a lay explainer, infographics,
A video, and also an article that’s been published in Frontiers for Young Minds which is our journal for kids, and during this Deep Dive session, you will hear from many of the different contributors to this article hub and you’ll also have the chance to connect and ask your questions to them.
So, what have we got to look forward to together today? So, this is today’s agenda, we’ll kick off with Professor Martin Siegert, who will set the scene for today’s discussions. Sofia Palazzo Corner, lead author of the article, will be presenting on whether global warming will
Stop when we reach net zero CO2 emissions, and will examine what determines the temperature changes once we reach this threshold. The speakers will then come together in a panel discussion who will also be joined by Professor Joeri Rogelj from Imperial College,
Ben Sanderson from the Center for International Climate Research, Dr Charlie Koven from Lawrence Berkeley National Lab and Tessa Khan, founder and Executive Director of Uplift. We’ll then open the floor to questions from all of you, and finally we’ll then close off with Professor Joeri Rogelj who will be delivering some closing remarks.
So, our first speaker is one of the co-leaders of the Frontiers in Science lead article, Professor Martin Siegert from the University of Exeter. A few words about Martin. He is also the Field Chief Editor for Frontiers in Environmental Science; a renowned, a globally renowned
Glaciologist who leads the UK’s participation in ground based airborne geophysical programs, which have so far explored and charted the sub glacial environment across 40% of Antarctica. He’s also published more than 250 scientific articles in leading international journals, is previous co-director of the Grantham Institute of Climate at Imperial
College, and Martin is now the deputy Vice Chancellor of the University of Exeter where he’s also responsible for supporting the 2030 target for net zero greenhouse gas emissions at both the university and the county in which he resides. So, Martin, with that, a warm welcome and over to you.
Well, thank you very much Gilbert for that kind introduction. Just like with all scientific papers, each of the authors involved will have their own story about its origin and I’m about to tell you about mine. Mine involves an early morning cup of coffee
With Joanna Haigh, and Joanna and I were co-directors of the Grantham Institute at Imperial some time ago, and without going into too much detail about that conversation, it’s quite clear we had very different ideas about what happens to the climate and the
Environment of our planet after net zero emissions is established, or the Zero Emissions Commitment. And that conversation was interesting, we suspected many other people would have similar misconceptions about it from a variety of different perspectives as well. So, sometime later, with the help of Joeri Rogelj, who we’ll hear from later,
We configured a group of specialists from all around the world to discuss and debate the Zero Emissions Commitment, brilliantly led, I should say, by Sofia who we will hear from shortly to take us through the paper. We set ourselves about two or three months
To reach a consensus on this. Actually, it was probably more like two years I think of many discussions and drafts and working things through. But I think we’ve put together a comprehensive guide to the Zero Emissions Commitment and we hope it’s going to be informative,
Useful, and interesting. So, to tell us more about it, I’m going to hand over to Sofia who’s going to explain everything that we did. A huge warm welcome Sofia. Sofia is a climate science and climate policy PhD student at the
Center for Environmental Policy at Imperial. Her research focuses on Earth system extremes with the aim of fully representing the spectrum of possible temperature changes that occur, that could occur by 2100, and a very interesting background, if I may, an accolade of achievements. So,
Sofia has a professional background in management consulting at the Boston Consulting Group, energy and environmental research at Chatham House and quantitative risk analysis at Funding Circle. So, Sofia, a warm welcome to you, the floor is yours. Thank you, thank you Gilbert, thank you Martin,
And thank you to everyone joining us online today. So, I’m going to introduce this paper that we published with a question, which is probably the same question that brought you here today and was certainly the motivation for our study. That question is: will global warming
Stop when we reach net zero CO2 emissions? So, what do we mean by this question, what do we mean when we say, will global warming stop? Well historically, and of course still today, global surface temperatures are rising in response to anthropogenic CO2 emissions. We’ve
Burnt some carbon, we’ve got some warming and so the question is: once we stop burning that carbon, do we also stop our warming? Does no carbon dioxide being added to the atmosphere, mean no more warming? And another way to phrase that is how much additional warming are we committed
To after we achieve and maintain net zero emissions? What is the Zero Emissions Commitment? So, there are three things that can happen after net zero, to global surface temperatures. The first is that temperatures stabilize and the global warming that we reached at
The point that net zero was achieved is the same that we have going forwards, there’s no change. The second is that we could have some warming, some additional temperature rise after net zero, in which case, that global surface temperature will go up a little, or alternatively some cooling
And global surface temperatures would reduce. The Zero Emissions Commitment is then a number and it’s a number that quantifies that change in the global surface temperature between the point when net zero was achieved and some point in the future. And Zero Emissions Commitment or ZEC, as we will abbreviate it, can be zero,
Meaning no change and temperatures stabilize. It could be positive, indicating that there’s some additional warming, or it could be negative, indicating cooling. And so, the next question is, what is it that happens to the Earth system exactly after net
Zero and how does this affect temperature? So, if we, if we sketch out what’s happening to emissions at net zero. So, historically and still today anthropogenic CO2 emissions are increasing. If globally we stop emitting CO2 into the atmosphere, there are two things that we expect to happen. First, is the atmospheric CO2 concentrations,
Which have been rising alongside rising anthropogenic CO2 emissions, are expected to start declining. And that’s because CO2 in the atmosphere is expected to be redistributed to carbon sinks in the land, in the ocean, by the natural carbon cycle.
Now this on its own would be a cooling effect but it isn’t the only thing that’s happening. At the same time, we’re expecting ocean heat uptake, which has also been increasing as emissions have been increasing, to start reducing after net zero.
And this would mean that more heat remains in the atmosphere and on its own this would be a warming effect. And so, the question then is what happens overall to global warming? Is there a balance between this
Cooling and this heating effect, or not? And so, we can imagine it kind of on a scale. On one side we have heating due to this slowdown in ocean heat uptake, and on the other side cooling due to our continued strong land and ocean carbon sinks.
Now, if our slowdown of ocean heat uptake is perhaps a little more rapid than we anticipate, or our land and ocean carbon sinks are less strong than we expect, then this might result in some more heating after net zero. On the other hand, if our land and ocean carbon
Sinks remain strong or if our heat uptake reduces less rapidly than we’re expecting, then we might get some cooling after net zero. But it’s important to bear in mind that we care both about the magnitude of these effects and also the rate at which they change,
Because they need to cancel each other out not only at the beginning but going forward. So, if we go back to this picture that illustrates the question that brought us here, that balance is represented in this uncertainty range that we see on the
Right-hand side after the point of net zero. If we had balanced it one way, we might expect a little more cooling and if we see the balance go the other way then perhaps some warming. Now our best estimate at the moment is that there is no further temperature change after
Net zero – that remarkably this balance is struck and continues to be over time. However, these assessments do come with an important and quite substantial uncertainty range and so that’s the second thing that we decided to look at in this paper.
And what we’re trying to understand is what these processes are that underly these two macro effects at the top – the heating and the cooling? What are these processes that determine temperature change after net zero? And so, what we did is we took our quite large group of co-authors,
Who are experts in different parts of the climate system, and we tasked them with trying to build a catalog of all of the different processes that could affect global temperature after net zero, and this is what we came up with: 26 levers of global temperature change after net zero.
We kind of accidentally built our own A to Z, and so these processes are organized into four subcategories. We’ve got land carbon processes, ocean carbon, ocean heat, and physical feedbacks. Now, these two on the left – land carbon and ocean carbon – they
Are processes that affect and determine, and are determined by, the natural carbon cycle. We’ve then got the kind of physics of the ocean and how heat is transferred between the different ocean layers and also exchanged with the atmosphere, and then we have feedback
Processes which affect, and are affected by, a number of those other three categories, and also other parts of the climate system. So, this is already a great resource for anyone hoping to study the Zero Emissions Commitment and reduce our uncertainty in it,
But of course ultimately what we’re trying to do is quantify the effect of each of these processes, and so that was the next step we took. The way that we did this is we gave a case study,
Or you might call it a scenario, and we asked our group of experts to consider a world where global warming was at two degrees at the point where we reached net zero. So, at the point where we reached net zero there’s been two degrees of global warming.
And we asked how much would each of these 26 processes move that global surface temperature up or down as a percentage of that initial warming?? And that’s what we’re looking at here. So, this figure has a few things going on, so let me just talk you through it.
On our x-axis we’ve got those 26 different levers – the A to Z. And on our Y axis we have the change as a percentage of that initial two degrees of warming and our two levels there are 1% and 10%. Then some of those are stretching beyond 10%.
The colors are indicating the groups – the subcategories. So, if we look at our key on the left, we’ve got land carbon, ocean carbon, ocean heating, feedbacks, and then the tone or the opacity of those bars is an indication of the confidence
That our experts had in those assessments. And so, this first panel here is showing the potential impact of each of these processes for global temperature change 50 years after net zero was achieved, so ZEC 50. We then extended that same assessment but for
100 years after net zero, then further for a thousand years after net zero. Now the first thing I should say, which is tempting, is that we can’t just add all of these bars up together and come up with a number, unfortunately it’s
Very much not as simple as that. But there are two things that we can definitely take away from this figure. The first is the number of processes where we see an impact of plus or minus 10% and sometimes even more, and that is not an insignificant change.
The second is the proportion of these bars where the assessment we can make is still only speculative and that’s a real indication of the uncertainty that we still have in a lot of the processes that affect the Zero Emissions Commitment.
So if we come back to that illustration of the question that brought us here, our results are certainly not disagreeing that our current assessment contains some significant uncertainty, but perhaps what we’re adding to this is that the uncertainty reported in our models at the moment
Is perhaps not telling the full story and there might be processes that are not yet included that could either stretch that uncertainty range wider or move it to one side or the other. And why is that important? Well of course if we assess that there is a plausible chance of
Significant additional global warming after net zero, that very much changes the implication of what it means to burn carbon today. So, of course our ultimate aim is to reduce this uncertainty, but to give you a bit of a flavor of how complex that can be,
We can plot it on a kind of simplified version of what the Earth system looks like. Just taking a handful of the processes that we have, we can already see how many connections we get. So, just starting with the atmospheric processes
Here and bearing in mind that the connections that are dotted are indicating processes that are uncertain in our current models. If we add on here the physics of the ocean we’re already seeing even in this very simplified version, connections between atmospheric feedbacks, and for example the pattern effect which
Is the pattern of surface warming on the ocean. Biogeochemical processes link the ocean and the land, and then we have land processes which are affected by things like land use and wildfire. So, we see this paper as being part of a four-step process to improving our assessment of ZEC.
The first is to identify the Earth system processes that drive this uncertainty and that’s what we’ve tried to do in our 26 levers. The second is to estimate their impact in different timescales and that’s what we’ve been doing with those bars that
You saw across three different timeframes. The third is then to try and reduce this uncertainty through targeted research and there’s more details on that in the paper, but we’ve listed out quite a long and detailed table with suggested research questions and modeling exercises. And of course, the ultimate aim is to build
Models that can better, or with a lower, with a narrower uncertainty range, give us an assessment of the Zero Emissions Commitment. So why is it important? What do we gain from knowing more about the Zero Emissions Commitment? Well perhaps one of the most important things to
Take away is that if the Zero Emissions Commitment is positive, if we can expect additional warming after net zero, that changes our assessment of how much warming we can expect from burning one unit of carbon today. And if we want to stay below particular
Temperature thresholds then the budget we have left to do that may be smaller than we think. On the other hand, if the Zero Emissions Commitment is negative, then we may be able to achieve more ambitious targets with the same action which would be fantastic.
And so, we’ve been talking a lot here about temperature stabilization, but unfortunately a world that has stable temperature or global warming that stops at net zero is not necessarily a world that has a stable climate. In fact, we know number of things that are that
Are guaranteed to continue changing. For example, sea level rise in response to the warming that we’ve already caused, disruption to ecosystems due to changes in weather, wildfires, droughts, the melting of glaciers and ice sheets also in response to the warming that we’ve already caused,
Ocean warming which will be disrupt the life that depends on the temperature there, and the same again for ocean acidification. So, if we were going to conclude with a couple of messages from this paper, they’d really be that the risk of additional warming after
Net zero is just another reason for us to reduce our initial disturbance to the Earth system as much as possible. And the second is that a world that has a stable climate, a world where global warming stops after net zero unfortunately is
Not equivalent to a world with a stable climate. In climate targets both mitigation and adaptation need to take these two things into account, and with that I’m going to hand over to the rest of our panel. Thank you. Thank you very much Sofia – it’s great having
That, I can only imagine the level of complexity it was to get all the data, 26 levers, and understanding the uncertainty and interactions between them as well. So, thank you for sharing that in a way that we can all identify with.
So, what I’d like to do now is to explore some of the issues that you raised there and also have some input from Martin and the Frontiers in Science article in a panel session that will be moderated by Martin himself. And a quick introduction to all of those
Who are joining the panel, we have Professor Joeri Rogelj, who is the current Director of Research at the Grantham Institute, who leads research training and innovation towards effective action on climate change and the environment. So Joeri’s work connects Earth system sciences
To the study of societal change and policy, and his work on climate change scenarios has informed international climate policy over the past decade, and he is a long serving lead author on the annual Emissions Gap Reports by UNEP and also on the IPCC reports.
He was also a participant on the transformational science panel discussion at COP28 which was hosted by Frontiers. Next up we have Ben Sanderson who is a climate scientist and Research Director of the Climate Mitigation Group in Oslo, Norway and his work looks at how to better characterize the uncertainties of mitigation
Technology and negative emissions alongside the development of statistical tools to highlight the conditional risks of mitigation decisions. We have Dr Charlie Koven who is a staff scientist at Lawrence Berkeley National Lab, whose research focuses on the relationship between climate change
And the Earth’s carbon cycle looking specifically at high latitude feedbacks. And he was also a lead author on the Sixth Assessment Report of the IPPC. And last but very much not least, I’d love to welcome Tessa Khan who is an international climate change and human rights lawyer who has
Spent decades supporting grassroots regional and international movements for justice, serving as an expert adviser to UN human rights groups and national governments. She’s also the Co-founder and Executive Director of Uplift UK, which resources, connects, and elevates ideas for a just transition away from fossil fuel production.
And to end this introduction with an impressive fact piece, in 2019 Tessa was named by TIME magazine as one of the 15 leading women in the fight against climate change. A huge warm welcome everyone and I’d love to now pass this over to our moderator Martin.
Thank you, Gilbert and well done Sofia for that really very well put together presentation about the paper. We’ve got a whole series of questions to ask. The first question is going to go to Joeri, and it’s this: Considering the policy and technological
Landscape, what are the most critical interventions or actions that can be taken to optimize our chances of achieving and maintaining a stable climate after we reach next zero? Yeah thanks, and also my thanks to Sofia for a great introduction.
If we look at the implications of what we have learned from this exercise and what this exercise has been further supporting and corroborated, there are key milestones that we need to take into account, and that also international climate policy as such needs to take into account.
And net zero or achieving net zero emissions is one of those key milestones. This research has not changed that in the slightest. What this research also shows is that there is some uncertainty about what happens thereafter. That uncertainty can fall in our favor and that’s really good, then we would be very happy,
But from a risk management perspective, which policy basically needs to pursue, it is rather the side where we see additional warming that concerns us most. Now the uncertainty there is not necessarily something that we will be able to avoid or
Reduce immediately, but that doesn’t mean that we can’t take it into account and prepare for it. And how can policy prepare for it? Well policy can, or policy and decision makers, can prepare for it and can take it into account by seeing net zero only as one step on the way
Towards a longer term stable or longer-term response to the climate change challenge, and really prepare for a world where we actively are able to remove carbon dioxide from the atmosphere. I think that is of course the long game. First things first. A key aspect in reducing
The risks that are implied by global warming and the Zero Emissions Commitment or the potential Zero Emissions Commitment, is of course to reach net zero or to stop adding CO2 to the atmosphere as soon as possible, and keep those cumulative emissions until then, to as low levels as possible. Thank you Joeri, wonderful,
I’m going to bring in Tessa now. So, as I said in my little preamble at the start, I thought I knew about the Zero Emissions Commitment before I had that cup of coffee with Jo, and it quickly turned out that I didn’t, and also it turned out that it was
A lot more complicated than I first imagined. Given that it’s complex but important, how are we going to explain it best to policymakers who might not necessarily have scientific expertise? How do we do that? Well, actually I think Sofia’s,
And hello everyone, I mean I’m really delighted to be part of this discussion – thank you to Frontiers for the invitation to join you, and to Sofia for the really clear presentation. I was just about to quote Sofia actually and thinking about how best to encapsulate
I think some of the findings of this research. And that was really I think Sofia you said that reaching net zero emissions doesn’t mean a stable climate, whether that’s still the possibility of increased warming or increased cooling. And I think that that uncertainty,
Because the risks are obviously much more considerable, if there is up to 0.3 degrees of additional warming even after we reach net zero. I think what that reinforces for policymakers which to be completely honest given the amount of uncertainty that’s built into
So many of the risks associated with climate change, I think what we have to insist on, is that policymakers abide by the precautionary principle, which is a principle that’s you know existed under international law and in international policy for decades, and basically
Means that where there is uncertainty, if the threat is great, then that shouldn’t be taken as a reason not to take action, precautionary action. And I think that this research really underlines the importance of that way of thinking, and indeed that principle in informing policymaking
So I think it’s not an entirely new dynamic, I think, for policymakers to keep in mind. Do you think many policymakers are even aware of the concept of the Zero Emissions Commitment? I don’t. I mean I think that my experience is in short, no. There is always a remarkably,
I think, superficial engagement, you know from the perspective of people like us who think about these issues day in, day out, with the science underlying all of the policies and of climate change that we discussed, so I imagine this would be new to most people, yeah.
Yeah, so good for us to discuss it here, of course I mean given that the first step towards the Zero Emissions Commitment is zero emissions, what are the sort of regulatory frameworks and government policies that are needed to overcome the practical challenges just to get to that point?
Well I think that’s the discussion that we’ve all been having for many years now given that net zero, I mean obviously after the endorsement of the Paris Agreement in 2015 that’s emerged as the sort of collective North Star in policymaking, and now a net zero policy
Commitment covers I think most countries in the world, I think there’s generally an understanding as Joeri was saying that that means that we’ve got to reduce carbon emissions. Ultimately you know that’s the bottom line. And you know I will say that one of the
Good things that came out of COP28 in December is I think finally connecting that understanding with the role of fossil fuels. You know we had for the first time the language of fossil fuels appear in a COP decision text. An understanding that we need to transition
Away from fossil fuels, and ultimately it’s as simple as that. I mean obviously in terms of actually operationalizing that and transitioning our economy and our industries away from fossil fuels, that’s going to require a whole host of different policies and practices but I think you know it’s as simple as ensuring that we
Eliminate fossil fuels as quickly as possible from our energy systems and from our economies. Thank you, Tessa. Charlie, to bring you in. You’ll be aware of course that I mean 2023 was the hottest year on our record by some margin compared to
Others and the likelihood that this year will be equally if not warmer than that last year, I think it’s provoking some people, some scientists to predict a sort of runaway warming of our planet. Is that likely? And how is the notion of the Zero Emissions Commitment countering that type of idea?
Yeah, it’s a great question and yes again thanks everybody for this really interesting discussion. You know, I think it’s too soon to say, how out of, whether this incredibly hot year we’ve all just experienced, is going to be followed by an additional, you know, whether it really represents
A step change beyond just the proportionality of warming to our cumulative carbon dioxide emissions, versus if it’s just one extreme year. And whether we’ll see things back to the trend, the longer-term trend that we’ve seen. But I think one of the things that you do
See from this is the enormous disruptions to ecosystems that are happening – particularly things like the fires in Canada over the summer, is exactly the kind of thing that we don’t have a good ability to include in our coupled climate and carbon cycle models.
And these are the kinds of effects that we identify in the article as being real uncertainties about the size of the Zero Emissions Commitment. If these kinds of large-scale fires that that we saw last year and in Canada, if those become regular features because of legacies and
The lags of the ecosystems to the warming, can continue long after the warming has stabilized. Those are the kinds of things that could be contributing to you know a more positive Zero Emissions Commitment and prolonged warming. And so I think these extreme years that we’re seeing and
The legacy of responses to ecosystems and as well to impacts around the world in response to these extreme years like last year are what we need to really focus on in order to reduce our uncertainty and understand how these abrupt changes that we start to see, whether or not those you lead to
Longer term legacies. Thank you. I mean I guess the way to quantify predicting our future has to lie with models one way or another to do that. How good are our models? They’re needed for that issue, are they up to
The challenge of doing what we need them to do? Yeah, I mean I think the difficulty of a metric like the Zero Emissions Commitment is that it’s not just the physical climate system, it’s the coupling between the physical climate system and the ecosystems both on land and the ocean. And so
That’s an extremely difficult problem right, and it’s in particular the representation of ecology in these models is not as strong, say, as the representation of the physical climate system. For a long time the legacy of development of physical climate models versus quantitative
Ecosystem models is the ecology part of is not as well developed and I think that’s one of the key things that we need to better focus on because particularly because these legacies in the system – a lot of them are driven by ecology which is not always been thought of as a as
A predictive science, the way weather prediction, which then gave rise to climate modeling has been. And so, it requires a very deep assessment of the uncertainties and understanding, and so we’re building them, they’re getting better, and they tell us this information that we have, and it’s
Useful information but it could always be better. Thank you, Ben. On this issue really, so surface warming is going to stabilize quite quickly after next zero emissions, but the sea level rise and ocean acidification that continues potentially for centuries due to committed deep sea warming and ocean acidification etc., how is this sort
Of disconnect between stabilized warming and continued other effects going to be affecting adaptation measures and climate resilience? Well, I think we have this idea of net zero being a specific point in time but it’s really just one mile marker along the trajectory of
Decarbonization, and in the real world hopefully we will reduce emissions and then as soon as we do so we’ll see different effects emerge on different time scales and we’ll learn a lot. As soon as we start reducing emissions, we will see how different elements of the Earth system
Are responding to those emissions coming down and this question of zero emissions, we’ll have a much better idea as soon as we start reducing emissions and we see what the Earth system does in response. And it’s the same for sea level and ocean acidification – there are different processes
Which influence this, and they will emerge on different time scales and the models which tell us about sea level rise in particular remain on the cutting edge really of what we can do with our system models. Only a few of our system models have interactive
Ice sheets which tell us about the potential time scales and melting rates and their sensitivity to both existing warming to date and any additional warming which you would experience. But the uncertainties are quite big and so we’re going to have to live with those uncertainties in
Sea level projections potentially for centuries to come. And that part of the equation, so, it’s going to be a long time before the uncertainties get reduced – other parts of the system, we might learn something quite quickly, as soon as emissions start to come down.
I’m interested in the other disconnects as well – I mean we talk about global climate stabilization, but does that mean stabilizing the weather systems on our planet – will they remain the same? I don’t think we should expect the weather system to stay the same. I mean global
Surface temperature, even if ZEC is zero, so the discussion this paper focuses on this global mean temperature response after zero emissions – but a zero global mean temperature change can hide evolving patterns of warming in the ocean, as the deep ocean temperatures begin to warm,
Equilibrate, and then you get transfer in the ocean – and that could result in weather systems which, and weather patterns, which continue to evolve over time as the system adjusts to a new equilibrium state. And in order to understand what that looks like,
We need to build better models clearly but also we have to acknowledge that different models currently respond in quite different ways and with post net zero emissions conditions in some models, ocean overturning circulation slows down and these can have effects which emerge even a century
After net zero has been has been achieved. So, yeah, again there is some fundamental uncertainty there that means that climate change even in an optimistic scenario may be with us for centuries to come and will continue to change. So, Joeri, climate scientists are really good
At acronyms so the ZEC is the Zero Emissions Commitment and the TCRE is the Transient Climate Response to cumulative Emissions of carbon dioxide. In combination they provide a sort of means by which we can estimate carbon budgets consistent with temperature limits. Do you believe the carbon budget framework
Adequately captures the uncertainties relevant to guiding our pathways, emissions pathways? Yeah, it’s a good question I mean the common budget framework in one sentence is the fact that we have a total budget of CO2 that can’t be exceeded if we want to limit warming below
A certain temperature level. So, the total amount of carbon that we can ever emit is limited. I think that is a very a very strong and powerful first order framework and for all the challenges that we are dealing with currently, it’s a very
Good framework, I think. And to be sure the challenge we are dealing with now is that our emissions are still going up globally – they have slowed down, the annual emissions, the increase has slowed down, but they’re not going down yet, and to reach net zero they need to go down quite
Steeply from the more than 40 billion tons of CO2 that we are emitting in the atmosphere. Now, where the carbon budget concept and the framework and the interaction between the Zero Emissions Commitment and the kind of linear relationship between the
Total amount of CO2 and global warming might not be the perfect tool anymore, that is if we are in a world where we have to start caring about the second order effects. And those second order effects we will see if we start to become close to zero,
And so I think until then this budget concept is still very valid. It has actually been proven to be also quite robust for projecting what needs to be done if we might be missing a target and we try to try to return. Also there, it’s a first
Order approximation, but in order to communicate between very complex scientific understanding and systems and with policymakers, and to make that translation, I think it’s a very powerful tool. So, but that doesn’t mean that the scientific community can’t start to think about how we
Can more accurately use Earth system information at the time when we would have already reduced our global emissions by 90% or so ideally over the coming decades. Okay, Tessa on policy work, so your policy outlook paper highlighted the tension over the language regarding fossil fuel phase-out in the COP28 negotiations for example,
How can clearer, more universally accepted terms and commitments be established to facilitate the rapid transition from fossil fuels? That’s a great question and I think that the hugely contentious nature of the language around fossil fuel phase-out at COP28, which ultimately
Resulted in fairly weak language around transition that was heavily caveated at the national level, I think reinforces the importance of these conversations actually taking place at the national level, because reaching international consensus on these concepts and exactly how to express them is just so fraught. And I think the closer we get to
Addressing the root cause of the problem, the more entrenched I think those countries and constituencies that benefit from the current system are likely to fight back, and I think we saw some of that emerging at COP28, with a sort of contingent of countries who are
Heavily invested in fossil fuel production for example, really refusing to compromise. And given it’s a consensus process at the UN Climate Summits, it just makes it very difficult. So, I actually, I mean I agree with Joeri that the concept of a carbon budget is one, and not
To make discussion too UK-centric, I appreciate a number of us are in the UK but you know that’s been translated, in to national policymaking in the UK I think to great effect, in the way that there is real accountability for five or six yearly carbon budgets for the UK government at the
National level, and that’s obviously a translation of the global carbon budget into what policymakers consider to be appropriate at the national level. So, I think if yeah if there’s a way of reinforcing some level of certainty around what the global carbon budget is and then enabling
National policymakers to translate that into a national carbon budget which you know in my view should then be adapted to reflect principles of equity so countries like the UK moving faster and ultimately having less of that access to that carbon budget than other countries for
Various reasons, then I think that that’s a really strong basis on which to continue policymaking. I guess there are initiatives like Beyond Oil and Gas Alliance and the call for The Fossil Fuel Non-Proliferation Treaty, those organizations in vital important for this this transition.
Yeah, they are right and I think, I mean, the Beyond Oil and Gas Alliance, I think is a particularly powerful initiative because it is a multilateral initiative, it’s the diplomatic club, basically of countries that have decided to end oil and gas production or set an end date for oil
And gas production have decided to end new oil and gas licensing. You know that’s very useful in so far as I mentioned earlier, it spotlights fossil fuels as needing phasing out. Whereas I think just discussing emissions reductions can sometimes avoid the root of the problem which
Is that need to transition away from oil gas and coal, and I think you know, it’s exactly those kinds of initiatives that are helping to build momentum towards the transition away from fossil fuels that are desperately needed and it’s great to see them starting to get off the ground.
Thank you, okay Charlie in the article as Sofia explained really nicely, 26 levers of global temperature change after net zero, that’s a lot of complexity, going back to what we sort of talked about before, how confident are we that we’re able to predict the trajectory
Of global temperatures post net zero and what are the major sources of uncertainty in all of this? Yeah, so the part that I focused on in the article was the land ecosystem, the land carbon cycle response and the various processes which include things like permafrost
Thaw and the legacies of permafrost thaw in terms of carbon emissions, and as well as wildfire and dieback of forest in the in tropical ecosystems and boreal ecosystems around the world. What all those things have in common is the legacy of the ecosystems to prior climate change,
Prior disturbance, prior land use change and these are the things that, because we are focused on, you know what are the remaining uncertainties, these are the things that are still the most highly uncertain, these slow legacy responses to things that had happened you know decades before,
Because you know the essence of the idea that ZEC is small is, you know, as Sofia explained, is this this trade-off between the sort of declining CO2 uptake on land, in the ocean, and the declining heat uptake, and so it’s really about the rate of that decline,
The relative rate of those declines, and because you know the relative rate of those declines is, you know a function of these time scales and legacy responses, those are the key things that we need to focus on. And again because we’re focused on the article,
On the biggest remaining uncertainties, you know those aspects of the system are quite uncertain and that’s why if you look at the current set of climate models they give us this uncertainty of you know about plus or minus, a third of a degree Celsius, you know that uncertainty that’s
Represented in the models is then reflected in the widespread ensembles of these coupled carbon climate models, and so again you know these models are useful in that they tell us something that we can use to influence our policy, but again, in order to improve them,
In order to narrow that uncertainty that’s what we need to focus on or better understand these legacies of the carbon cycle to the response. Thank you. Ben, on this issue on uncertainty, okay so money no object, geographical location no object, where should we best target research
That will most reduce uncertainty on this issue would you say, you know you, might talk about your own research or anyone else’s? That’s a big question, so I think well let’s say firstly one thing which was good about this article and is rare,
Is it didn’t just talk about what’s in the models, it also talked about what’s not. And attempted, you know, even though it’s difficult, attempted to sort of like order magnitude assess what the magnitude of those processes which are not in the models is, and
So that that’s a useful exercise in informing the question that you’re asking, is okay, well, that’s how do we triage? How to include processes in the models which are not currently represented? And so that exercise is a direct useful takeaway from this article and aside from that we need to think
About how to deploy the resources that we have. I know you said that money was no object but as we move into another big round of IPCC Assessments it’s useful to think about what resources we have
On the table and what experiments to do to better get our handle on these questions moving forward. So involved in that is how we use the different types of models we have on the table. We have some complex models like several of us work on here, like Charlie, and we have lots
Of different sort of simple models which allow us to sort of more look in a more formal statistical sense at all of the uncertainties in the problem. And so what we’re trying to do now is how to use those two different types of model in parallel, noting that neither one is perfect.
The complex models we can never run them enough times to get a full grasp on the uncertainty and the simple models we know there’s a bunch of stuff missing and so you know, we need to sort of mash these things together in a way that gives us a better
Understanding of what’s happening moving forward. And then together with that, you’ve already raised the issue of like 2023 and how that’s taken some climate scientists by surprise. That’s the other element of this, how can we get more efficient at more rapidly incorporating observations which
We have of the climate system back into the models to influence how they’re calibrated and what processes are missing and so with that in mind this question of ZEC, the Zero Emissions Commitment, is one of the few which really matter in terms of framing policy.
Another one is what’s going to happen as the aerosol emissions come down, I think that’s really been highlighted as a big uncertainty which we need to do better really rapidly. And then how do we incorporate observations for example from satellite
Time series’ which are now becoming mature enough to actually be used as ways to either to determine between good models and bad models so there’s a lot of things which are happening simultaneously which we need to incorporate. Thank you, I was rather hoping you’d say
Deep field Antarctic glaciology research is really needed but let’s have another conversation about that! Final question to Sofia, and thanks again Sofia for organizing us and for putting all this paper together, is net zero enough or should we be aiming for negative emissions, and in that case how do we do it?
Good question and I’m glad that you phased it like that and not, ‘is net zero worth it?’ because it absolutely is. Well, I think this paper has highlighted that perhaps zero won’t be enough although it is absolutely required,
And I guess that in order to answer that question we need to be able to look into the future a bit and know what level of warming we’ve reached at the point that we’re at net zero. And if it’s quite high then absolutely we’re going to want to bring that temperature down
And the way to do that is through net negative emissions, so yeah, I think the it’s a bit of a case of the more that we know the more that we notice our uncertainties and the more that
That tells us that we need to keep global temperatures as low as we possibly can in the first place. And if we can’t do that then to bring them down as much as possible afterwards. Thank you, Sofia. It’s good to know we’ve got an awful lot of questions coming from the Q&A
And so with that I’m going to hand back to Gilbert. Thank you, Sofia, thank you Tessa, Joeri, Charlie and Ben. We’re going to hand back to Gilbert he’s going to take us through the audience Q&A from here. Thank you ever so much. Thank you, Martin. It was a really great
Discussion for charting a real path forward. Yeah, we’ve had loads of questions coming in thick and fast and a lot of them are elaborating on the points that all of you mentioned, so I just picked a couple out and hopefully this will add a little bit more depth to this discussion. So let
Me just get started and I think the first question I’d like to discuss is actually perhaps one of the most challenging ones and it’s on the practical challenges of reaching and sustaining net zero emissions and as moderator Martin, I would love to kind direct this one to you if I may.
So, you know Tessa mentioned that we know the outcome of COP28 about the importance of vocabulary when we talk about the fossil fuel industry, phasing out, phasing down, transition away. So, the fossil fuel industry and its enablers remain a major obstacle to achieving that zero and this we all know.
What can academics do to minimize the fossil fuel industry’s influence on international policy and politics? Well, that is a terrific question, thank you and not an easy one, but then again you know, maybe it is an easy one. There are,
When we talk about the fossil fuel industry, it’s a wide variety of different types of companies, different types of behavior, different appreciations of the climate problem, so it’s easy to sort of put them all, lump them all together, as the fossil fuel industry,
But actually, it’s actually quite diverse. There are some people who think we should simply not have anything to do with the fossil fuel industry and put them all into one place. I don’t know what other members of the panel are like but I’m not in that position for two reasons.
Firstly, actually there are some companies that are more enlightened than others and it is, I think, appropriate to work with companies that are serious about the transition to net zero and not work with the companies that clearly, through their records and through
What they say actually, they’re not at all. The second reason I’m interested in continuing dialogue with this industry is that they’ve got tremendous expertise built in, in terms of putting very large bits of kit in difficult places, raising amounts large amounts of income,
Investing in that, making it work financially, turning into a profit, providing energy to our global system, that’s exactly what we need to advance renewable energy at pace and at scale. And so just to say we’re not going to work at all with the fossil
Fuel industry stops us working with the very companies that are good at doing what we need. Now there will be some fossil fuel companies that you just know won’t do it because they obfuscate and they, you know, they lobby against climate actions and so don’t work with those,
But there will be some and hopefully more into the future that maybe do get it better and it’s for those companies and it’s for each of us to work this out, it would be for those companies that we should maintain our focus I think. Thank you very much Martin.
Tessa, I don’t know whether you have anything you’d like to add to that. No, I actually I appreciate Martin’s perspective on this, I think. I mean I think it’s right that there is diversity in the fossil fuel industry. I do think though, that you know, it’s important
To bear in mind the sort of the gulf at the moment between the sort of rhetoric that we’re often hearing from the industry in terms of the role that they’ll play in the transition and where their capital expenditure is going and their investments are going, and I think the real,
So you know the International Energy Agency, one of their recent reports made it clear that fossil fuel companies are responsible for only 1% of investments globally in renewable energy generation, so overwhelmingly it’s not the fossil fuel industry that’s currently driving
The transition, and I think that for a lot of us, the last year or so when the industry’s been making record profits, you know, has been a real test of the intention of that industry to play a part in the transition. And what we’ve seen overwhelmingly is that they are paying out
Their shareholders and paying off debt and they’re not investing in diversifying their portfolios. In fact, we’ve seen rolling back of some of the commitments to expand renewable energy production from some of the carbon majors. So, I mean, I certainly appreciate, and you know,
We work with the oil and gas workforce in the UK because they absolutely do have the skills that could be repurposed for, certainly if you’re looking at offshore oil and gas into offshore wind for example, and I think it’s very important to think about how to harness
The expertise within the workforce, but I do think that you know it’s really important to be quite discerning about which companies are acting in good faith and which ones are trying to take advantage of the reputational boost they get from talking about being part of the
Transition when their investments and you know where they’re putting their money belie that. Thank you very much Tessa. I guess that’s a contentious topic that we can talk about for a very long time, but I would like to now pivot the discussion,
And maybe let’s look at the modeling and the work that Sofia was presenting, and we actually have a question from one of the co-authors that came in, Gabriele Hegerl. I guess this will be for all takers, but I’ll read it out and it’s about,
It’s about the evolution of the earth system processes after reaching net zero emission. So the question is: as you said, land vegetation responses are highly uncertain and most earth system models don’t couple it fully (of the five with fire in the recent IPCC carbon cycle chapter,
Only one or two also have interactive vegetation). To understand what happens in response to extremes, for example, like some of the ones we see, we need to know about these interactions. How can we entice modelers to fully couple it even though it is difficult and may go wrong?
Is there a way we simulate the future models that can be still appropriate? The community is definitely doing this, right, we’re building models that do a better job, each successive generation of earth system models includes more processes than the prior ones.
If the table that Gabriele is describing if we, you know, if that equivalent table was there in the prior IPCC report, now I can’t remember whether or not it was, you know, it would have a lot more sort of missing processes than the one for the sixth assessment report.
I think we expect the seventh assessment report to, when it comes, to have more models with more processes, but it’s slow and I think that, so much of the focus right now, and historically, has been on increasing the resolution of the atmospheric models and in these physical processes
And I think a somewhat smaller focus has been on representing the fidelity of ecosystem models in the land and the ocean in these coupled earth system models, and so it takes you know to sort of, the point that Ben was making before, it takes some prioritization and it takes resources and
It takes better data and observations. We can only build these very complex models if we have very good observations from satellites and from field observations etc. I mean we need all these things together right, there’s no single solution to every, you know,
That’s going to make our models great. It’s a whole large set of interacting processes and a whole large set of interacting institutions and observational resources and modeling resources, so all these things are needed together, and it just takes time and effort and people and resources. Thank you very much Charlie,
That was a quite a challenging question that your co-author also shared. I’d like to maybe kind of pivot this back now thinking about monitoring and measurements, so we have a question here from someone called Cheng-Zhi Zou and it’s on the research priorities for
Reducing Zero Emissions Commitment uncertainties. So, the question is: I appreciate the talk on the uncertainties in the projection of future climate change. To narrow down the uncertainty, we need to have better climate models. There are multiple studies showing that the current climate model simulations of climate trends are much warmer than independent satellite
Observations which have global coverage. How can the climate model community take steps to improve the climate model simulations to have better agreement with these recorded observations? Would anyone like to take that, I don’t know Ben if you would like to tackle it?
Yeah sure, I mean, this question of whether the current models are too warm or not is constantly moving, it’s constantly changing, we get more observations all the time. Last year was very hot, we still haven’t, you know, the papers, which disentangle how
To interpret the models we have given last year’s observations, haven’t come out yet, so that would be, my first point is that, this is the conclusion which the next assessment will have on current models will be different to this one. And also, there are lots of different lines of
Evidence here. It’s not, there’s no single axis through which a model can be better or worse because a climate model simulates thousands of different processes in different parts of the Earth’s system. One way to assess it is through global mean temperature but also you can look at any aspects of local climatology or
The land surface or the carbon cycling or anything else, so we need to then process that information to say what they mean. How can we build better? So, the question was framed as we need to build better climate models to have a better, to reduce our uncertainty.
I would say it’s not quite as simple as that. We need to identify our uncertainty, there’s no, firstly, there’s no single way to assess when a model is getting better or worse. You know, you have to come at this from lots of different directions at the same time,
But also you have to be satisfied that you’re sampling the degrees of freedom which you have in that model to sample processes. So we need to be confident that our samples and our sampling strategy are exploring the degrees of freedom which we have in order to be confident that we’re
Not missing a potential worst case scenario. Thank you very much. Would anyone else like to speak to that or I can move on to our next question? Yeah, oh okay, Joeri, would you like to kick us off. Maybe I also want to actually link this back to what Ben mentioned earlier.
The most complex models that we have are extremely expensive to run. We will have one calibration of them and we don’t expect that calibration to be perfectly in the center of the distribution. That means that we can’t just rely on these most complex models to give us the best estimate,
Central estimate of our projections. Instead we can use this kind of ecosystem of modeling, models with the most complex, the most advanced ones and then simpler ones, that can be run thousands if not millions of time and that can capture all the uncertainties
Included, then have a median response that is really also consistent with the kind of median estimate of what happens, happened in the observations, and it’s really this interplay between these different levels of complexity of modeling that needs to be further developed.
We saw a first really good indication of this actually in the last IPCC assessment report where the most complex models, the temperature projections of those were not taken as the standard by which future warming will be judged. They were taken as information, as insights that
Are then integrated in our assessment of what future warming will be and it is this kind of integration of these different lines of evidence that is really very important and will become ever more important in the future. Thank you very much, and Martin you wanted to…
Yeah, thanks Gilbert. Briefly and just to sort of exemplify this issue in Antarctica last year. The sea ice in Antarctica was reduced over winter by an area about 10 times the size of the United Kingdom, that should have been covered by ice on the ocean and it wasn’t.
And it was remarkable how little it was and how far away from previous years that ever was. It’s been happening in the Arctic for some time since really, since the 1970s that we’ve been revealing that Arctic sea ice has been lost. Up until 2017 that really wasn’t happening
In the Antarctic but most climate models kind of had that, you know, the Antarctic sea ice behaving kind of like the Arctic and I always wondered why that was. Maybe the Arctic the models are just overheating, maybe they’re doing this. Actually since 2017, the
Sea ice in Antarctica has been getting less and less, and this year remarkably, so it just might be the models are right after all and there’s a lot of sort of variability and uncertainty in the Southern Ocean but actually over the long term, they’ve probably got that right.
Well, that actually leads to a great follow-up question about the predictability of these models, and it’s good to see, you know, empirically, you managed to get them pretty accurate. So, I actually have a question that comes in from one of the Frontiers’ chief editors so
That’s Professor Michael Heinrich, so a warm welcome to you, and thank you for joining us. So, this question is to Sofia, and you have partly answered this, but I think it’s just nice to see the research direction you’re going to go into. So environmental systems are always fluctuating
And there is a high level of uncertainty, a point that you highlighted very eloquently. So, Sofia, what do you think is needed to increase the predictability of these models or the next stages, I would say? Yeah, thank you for the question. I guess
This is the part of the paper that I didn’t really go through in the talk because there’s quite a lot of information that comes with it. But one of the main things that that we tried to do was really articulate what it meant for research taking each of these processes and
Trying to improve the predictability we have about them. So, I would perhaps inconveniently refer you to our paper where we have that that full list of the 26 processes and suggestions for research questions and then beyond that, suggestions for actual modeling exercises that either are
Waiting to be done in the sort of near future or that we need to make some effort to make happen. And we’ve really tried to prioritize those via like a few different dimensions, so whether we already have, we may already have like the correct materials
To be running some of these experiments separately from our most complex models, so it might be that we have a model that just runs something about land carbon or just runs something about CO2 exchange between the ocean and the atmosphere or whatever it is.
And that trying to reduce our uncertainty in a certain measure that can then be fed into the more like coupled comprehensive systems. And so we’ve made an assessment based on that what’s available at the moment but also what the kind of big modeling exercises are
That are coming up in the future that we know about, and also the big reporting exercises, so the future IPCC reports and also the coupled model intercomparison projects and thinking about how this question can be integrated into those exercises that we know are going to happen anyway.
And then the Zero Emissions Commitment model intercomparison project, which has been run separately and underlies a lot of the kind of question that came that led to this paper coming about in the first place, there’s going to be a second iteration of that as well.
So certainly, there are things that are going to be put into practice going forward and if you’re interested in what those specific questions are, if for example you’re interested in forming some of those pieces of research then that would be a great resource for you.
Wonderful Sofia, thank you very much for sharing that. I’d like to follow this up with a question, we’re all familiar with the nine planetary boundaries, so this will obviously have an impact on how we understand our interaction with our natural world, and I just want to paraphrase this question somewhat because
I think it’s kind of missing a point. So, this is a question from someone called Leonard Neamtu on the implications of Zero Emissions Commitment uncertainties for climate policy. Should the planetary boundary thresholds be adjusted if we’re considering the possibilities of what would follow a net zero world? That’s an open question if anyone
Would like to take it. Joeri, I see your hand up. Yeah, short answer, no, because the planetary boundary, well as currently defined, there are nine of them, looking at different parts of our planetary system and one of those boundaries is on climate change and for example on CO2 concentrations and climate forcing.
They are kind of on the interface and they strike a balance between scientific evidence, scientific understanding, and ultimately value judgment of what we consider safe, what we considered acceptable, and what threshold should not be exceeded. A similar question or has been answered by countries under the Paris Agreement
And they were asked what is a safe level of warming, or what is an acceptable, I don’t think they would call it safe level of warming, and well they translated this in that the aim should be to keep warming well below 2 degrees, while pursuing to limit it to 1.5.
So, that’s a similar kind of boundary, well that boundary should not change with this information. The implications of what we need to do to stay within that boundary, or to stay within the Paris Agreement temperature goal, yes that should take into account the information of this research.
And well I already highlighted some of those implications before. There are implications for how large the remaining carbon budget would be, there are implications for what we do after net zero, there are implications for how we prepare today for that later eventuality. Great, thank you very much Joeri, that’s super clear. Anyone else
Would like to share on that? We’re all good? Okay, we are running out of time, but I’d like to just bring in Tessa in again to perhaps speak a little bit more about climate policy and elaborate what you were saying before. So, this question is from someone called
Amelia Delgado and it’s the implications of Zero Emissions Commitment uncertainties for climate policy. So, Tessa, thank you for reminding us of the precautionary principle. It should be widely known however from experience that environmental related risks seem to be categorized in some special category and they’re not
Regarded in the same way, and they’re discarded. So, any advice on how we can make it more visible, make these more visible to decision makers? Yeah it’s a great question and I think it’s, you know, it’s a frustration that lots of us who work on climate change policy,
And who also understand how long the precautionary principle has been around in sort of international law and policymaking, it’s frustrating that it’s yet to translate I think in any persuasive way into domestic policymaking, although there are some exceptions to that where environmental
Impact assessments, for example have incorporated the precautionary principle when thinking about the approval of big new infrastructure projects. But I mean honestly, I think that just the fact that, you know, as we’ve been discussing, the last year was warmer than people had predicted,
That we are sort of starting to see how the uncertainties that we’re grappling with can often mean that risks manifest sooner than we expected and not later. I actually think that the evidence that people are experiencing, directly physically seeing
Around us, you know, policymakers aren’t immune from that, and we know just in the last year, every continent more or less has experienced I think some manner of extreme weather event or the implications of our changing climate in a way that’s affected their local communities.
So basically what I’m saying is, I think, the case is easier and easier to make with every passing day and I think it, intuitively is more and more appealing as we see more evidence of our failure to take account of those risks and act in a precautionary way.
So hopefully the external context in some ways is going to make that task easier. Thank you, Tessa. It sounds like a complete double-edged sword, but yeah I think the fact and the reality that we’re all facing, it should usher in more climate action on policy fronts.
So, I’d like to now end this with something a little bit more positive, and after reading Michael Mann’s editorial about how technology and the ‘know how’ actually we’re there but the actual obstacle is policy really, but then we also are thinking about
Capacity building for the next generation, right? Like we know that we’re going to be passing this on and this is an open question for anyone who’d like to share. What do you hope schoolteachers are doing to help the next generation to understand the latest climate change research
And the roles they can play in mitigation and adaption? Is your research relevant to climate change education in schools? I’m happy for the first person who’d like to put their hand up to take it. I imagine that all of us care about the
Next generation and the leaders of tomorrow – that they’re at school today right, and the better we can equip young people with the determination and with the knowledge and the skills that they’re going to need for the next 40 years, which is the net zero transition period, the better it
Will be, and so we have an obligation to talk to school kids about this and to be open to it. Now, something like the Zero Emissions Commitment, and it is quite challenging, you don’t have to start at that position, that’s kind of quite advanced level stuff,
But the great thing about climate research is that it’s easy to engage a broad audience with it because it’s our planet, right. We need to fall back in love with nature and with the planet and in my experience, and I go to many schools and secondary
Schools in the UK all around the country, the level of engagement is spectacular. Kids really do want to understand and know about this, and as I say, it’s our obligation especially those of us who work in research institutions and in universities to reach out to those, because
In 10 years’ time, and then afterwards, many of those will be working as we do now in this area. We must advance things, we must pass on knowledge and for the next generation to build on it as rapidly as possible, thank you. Thank you, Joeri would you like to share?
Just adding to this, I also wanted to highlight the resources that are already available, and actually Sofia led an additional paper in Frontiers for Young Minds on this topic, for example, as an explainer to school children which might already be a starting point.
There are also lots of initiatives including research projects to translate earth system signs for mostly primary and secondary school children. So there are really targeted resources available and I cannot agree more with Martin that we need to equip the next generation, at the same time
We should not abdicate responsibility because the decisions that need to be taken need to be taken today, and the actions that are actually required for a safe planet or the actions that happen in the next 5 to 10 years, and that’s when they are still in school.
Thank you very much Joeri, that’s really useful. Any other final thoughts from anyone, maybe Sofia how did you find the… oh Ben sorry, I just missed you. Yeah, just very briefly, so questions like this tend to make us focus on uncertainties because
That’s the way the question’s framed, and they tend to underplay how much we are kind of confident about, and in this particular question we are confident that, as Joeri said before, the first order effect. Like every ton of carbon you put into the
Atmosphere you get a certain amount of warming, broadly that remains true, and we’re talking about like the second order details on top of that. And so, I think the first thing to do is communicate that a lot of climate science can be explained very simply, very clearly,
And then also be very clear about where scientists do disagree, like on mitigation strategy and what we should do about it and how we should structure technology and society and everything else. We have a clear open discussion about why different people have different opinions,
And so yeah, that’s I think there’s a job for climate scientists to sort of know, say what they know and why they disagree on what they don’t. Brilliant thank you, thank you very much Ben. I’m just cautious now that we’ve just reached the end. It’s 20 past so we can, you know,
Charlie if you have anything to share, you can also share in your closing remarks, but I’d like to say thank you to our audience and I’m really sorry we just scratched the surface with the plethora of questions that came in. It’s been an absolute pleasure to see how engaged
Everyone’s been, but I’d like to now close this and now just follow up with some closing remarks, and I’d love to offer the opportunity to Joeri, perhaps looking at the critical next steps for this research as you see it. Listening to, knowing the material,
Listening to the conversation that we had today, I think there, the critical next steps are really first and foremost to translate it to policy and to translate the insights and make sure that the consequences are understood. I mean, this evidence should incite action,
Not necessary surrender, but it is also clear that additional warming does not mean unstoppable warming, not at all. Net zero still becomes even more important as a milestone, but it’s not the end point of how society responds to the climate change challenge.
And there is uncertainty about how much warming we would get, which additional impacts there could be, the damages and the challenges, but this uncertainty doesn’t mean we cannot act. And from a precautionary principle, actually a precautionary approach allows us to take this
Uncertainty into account and hedge against these risks, and so the consequences there are clear. Emission cuts over the next years and decades become ever more important in order to limit the peak warming as low as possible, and besides those reductions,
Also investing in long-term removal of CO2 from the atmosphere as a key protective measure against additional warming becomes important. What that means for research, what I heard from today’s conversation is an important focus on better understanding the different factors that
Influence the Zero Emissions Commitment, that have now been identified by this study, and this better understanding can be built through modeling and observations. And we should particularly look at those factors that are currently only identified as speculative, that are not in the models,
And we heard for example, legacy effects of warming on ecosystems and ecology, but we equally heard not just the challenges of building a model but also the challenging challenges with the observational coverage and the observational evidence of the systems
That we try to model. If we have not observed them it’s really hard to build a strong model. Together these steps will really ensure that society is better equipped to respond to the climate change challenges and that we are, of the climate change challenges,
Which we are and will be facing over the course of the coming decades, if not centuries. Thank you, thank you very much Joeri. We are very, very close to running out of time so I’m going to give the panelists a challenge. If there is one word or phrase that you would
Like to share with our online audience as a take-home message, what would it be? Ladies first, Sofia, may I ask, do you have, how would you impart your knowledge? Well I think, yeah, the most important thing really is to echo what we’ve heard a lot today,
Which is that this uncertainty in the earth system does not translate into any ambiguity about the action we need to take. The message is still the same and it has been for decades, we need to reach net zero and we need to reach it as quickly as we can.
Crystal clear, thank you. Over to you Tessa. Yeah honestly, I don’t have much to add to that. I think just the urgency of the imperative to get to net zero given potentially the importance of getting to sort of net negative emissions, if it turns out that we fall on that side of the
Uncertainty spectrum, so I really just think that it underlines the importance of that really rapid and deep cutting emissions in the short term. Thank you very much. Over to you Ben. I think in addition to everything which has been said today, a great challenge is now to assess
Policies which claim to get us to net zero and really dig into the details of what’s implied, especially on the negative emissions side, so it’s a different discussion but I think that’s really important. Fantastic. Charlie. Yeah just that the zero missions agreement is, you know, it’s very closely related to this idea
That warming is proportional to cumulative emissions, and that’s the important model, the most important model is the one we have in our minds. All you really need to understand is warming’s proportionally accumulative to emissions, and if we just want to stabilize
Warming, we need just to get to net zero. Absolutely, thank you very much, and Martin. The co- benefits of decarbonizing are really important, right. The things that we care about on our planet will be protected with rapid deep decarbonization. If
We don’t do that, those things that we care about – the polar regions, oceans, and things, our climate will be devastated. So, the sooner we do this, the better. Those are very compelling closing words, thank you very much Martin. Thank you everyone,
To all our speakers and our expert contributors. Thank you, Sofia, Martin, Joeri, Ben, Charlie, and Tessa, and also thank you to everyone who joined today. I really hope you enjoyed the session as much as I did hosting it. So quick note, please do visit the Frontiers in Science website.
Do read the article that we’ve discussed today and explore the hub of content. There’s really, really, great material that you can get your teeth into. As I mentioned, the conversation is still going on social media so use the hashtag #FrontiersForum,
And also I invite you to subscribe to the Frontiers in Science newsletter via the website. So, for now a big thank you. Thank you to our panelists and have a lovely morning, afternoon, evening, and catch you at our next Forum. Thank you very much.