This paper is based on an interview with climate scientist Dr Pep Canadell. Canadell is Executive Director of the Global Carbon Project, a global consortium of scientists with its headquarters at the CSIRO in Canberra. Canadell has been involved in Earth system and global change science since its inception as an emerging field in the 1990s; he is a core ongoing participant in Intergovernmental Panel on Climate Change assessments; and a participant in key international negotiations such as the Paris Agreement. Some scholars note that new scientific insight developed through climate science has led to revolutionary ideas even more radical and challenging than Charles Darwin’s theories of evolution. Two objectives of the interview are: i) to gain insight into Canadell’s first-hand experience of participating in these new areas of scientific research with their revolutionary understandings of a quantitative shift in the relationship between humans and environment; and ii) to gain insight into Canadell’s experience of conducting a mode of scientific research that is also a form of social engagement and action for change. The interview explores how Canadell perceives his research activities as a form of evolving interdisciplinary and collaborative practice (involving scientists from very different disciplinary backgrounds) with great relevance to pressing socio-environmental problems. It also discusses potential roles of the humanities in these efforts; and ground-up initiatives for change.
Our interview took place in August 2017 in Canberra, Australia. The Oceans and Atmosphere offices of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) had, at that stage, been relocated during the refurbishment of their usual premises. So we met in quiet, temporary offices on the edge of suburban Yarralumla, backing onto pine forest and woodland. We sat in a ground floor meeting room in a modest 1950s brick building, overlooking an empty green sport field. When we met again the following year, the refurbishment was complete and we talked in a sun-drenched corner of a multi-storey state-of-the-art building, suggesting the hub of national and international scientific research that takes place there.
Canadell trained as a biologist in Spain during the 1980s and holds a PhD in terrestrial ecology from the University Autonomous of Barcelona (1995). When he moved to the U.S. in the nineties, he soon became drawn into the emerging field of Earth system and global change science. He was appointed Executive Director of Global Change and Terrestrial Ecosystems (1998–2003), a core project of the International Geosphere-Biosphere Programme (IGBP), which is renowned as a ‘landmark research platform that fostered exploration into workings of the planet’ and human influence on those systems (Future Earth 2016; Rockström 2016). The IGBP has been central to bringing knowledge of anthropogenic environmental change, including global warming, to public attention. And it is responsible for the formulation of influential concepts such as Planetary Boundaries and the Anthropocene, with the latter in particular attracting widespread attention well beyond scientific circles.1
Since 2001, Canadell has held the position of Executive Director of the Global Carbon Project (GCP), a core project of the large international research initiative Future Earth. Future Earth was announced in 2012 and builds upon three decades of work of predecessor programmes including the IGBP (1987-2015) and the World Climate Research Programme (WCRP, est. 1980).2 While the GCP comprises a global consortium of scientists working at dispersed locations, its headquarters are housed at the CSIRO in Canberra. At its helm, Canadell has published over 200 scientific papers and books on topics stretching from terrestrial ecosystems and the impact of carbon earlier in his career to, more recently, the development of global and regional carbon budgets;3 processes driving carbon exchanges between the biosphere (the region of the earth occupied by living organisms) and atmosphere; and ‘assessment of CO2 stabilisation pathways’ for the future (Canadell 2010: 209). He also conducts public outreach and communication work, publishing regularly in forums such as The Conversation. As a member of the United Nations Intergovernmental Panel on Climate Change (IPCC) he was awarded a Nobel Peace Prize in 2007. In 2017 he was elected a Fellow by the American Geophysical Union for outstanding contribution and discovery in Earth sciences and for contributing to scientific understanding needed to build a sustainable future. This fellowship is a great honour in his field.
Our interview ran for ninety minutes during which Canadell spoke generously and fluently throughout, expressing great enthusiasm and passion for his subject. Our conversation ranged across a number of topics. These included discussion of the Paris Agreement and the inadequacy of its targets in terms of limiting global temperature rise to 2° Celsius above pre-industrial levels; and Canadell’s observations of major ecological transformation already evident here in Australia due to a warming climate (Beudel 2018).
Two further objectives of the interview, which are the focus of this article, included: to gain insight into Canadell’s first-hand experience participating in a new area of scientific research known as ‘global change’ or ‘global environmental change’, which has come to understand the working of the Earth system in unprecedented ways;4 and to discuss Canadell’s insight into conducting a mode of scientific research that is also a form of social engagement and action for change.
In other words, I was interested in how Canadell perceives his research activities as a form of evolving interdisciplinary and collaborative practice (involving scientists from very different disciplinary backgrounds) with great relevance to pressing socio-environmental problems. Further to this, some scholars argue that scientific insight developed through climate science has led to revolutionary ideas as consequential and far-reaching as Charles Darwin’s theories of evolution. New knowledge revealed by climate science is ‘even more radical and challenging than Darwin’s’ in that the theory of anthropogenic climate change requires ‘a critical reassessment of the implications of the Industrial Revolution’ with its notions of progress (Griffiths 2013). Equally, it requires reassessment of modern capitalism (Tsing 2017: 19; Klein 2014) and demands political action and transformation at both social and individual scales (O’Brien et al 2013). This is a revolutionary idea not simply at an intellectual level but at that of lived experience.
Using more poetic language, Bruno Latour suggests that climate science has prompted the realisation that we live on a newly active, animate and responsive planet. Drawing on the work of philosopher, poet and historian of science Michel Serres, he proposes that the Earth is moved by us humans (Latour 2016: 1). Serres in his distinctive style puts it this way:
earth, waters and climate, the mute world, the voiceless things once placed as a décor surrounding the usual [human] spectacles, all those things that never interested anyone, from now on thrust themselves brutally and without warning into our schemes and manoevers. They burst in on our culture, which had never formed anything but a local, vague, and cosmetic idea of them: nature. What was once local – this river, that swamp – is now global: Planet Earth. … Global history enters nature; global nature enters history: this is something utterly new… (Serres 1995: 3, 4)
Whatever language used, these are times of revolutionary ideas with immense real-world impact, and scientists such as Canadell have been integral to their formation.
Working in a consortium-like manner
Saskia Beudel: When did you begin working in climate-related science?
Pep Canadell: In the early nineties when I moved to the US from Spain. I was exposed immediately to what was then an emerging research area and I got into it very quickly. I moved from doing my own research, which I did, to becoming part of the global community and driving the global community to work in a consortium-like manner to address the bigger issues that are harder to address by an individual scientist.
As we look at bigger and bigger problems — how climate works and ultimately how the whole Earth system works, because that’s what climate is actually. It’s how the whole planet, oceans, atmosphere, ice and land interact. The science has become a truly international endeavour. There’s a lot of work that needs to be done from a coordinating point of view. There’s no UN science body, there are just lots of great science bodies, and you need to look at ways to bring them together … and drive interest to do coordinated work.
Saskia: Was it the late eighties when the natural sciences, across the earth sciences and the biological sciences started converging in terms of beginning to understand an Earth system?
Pep: I would say a little bit later. It was really dominated at first by the physical world, the atmosphere, oceans and ice. The land was not much part of it. It was more of a passenger and not a driver, the land component. Because, truly, the oceans are ultimately responsible for so much of the energy exchange, the winds, therefore the transport and the mixing, so it was not until more in the nineties when a full appreciation began that the land plays a really important role indeed, of course, in models of study to bring together the full Earth system model.
We don’t call them climate models anymore. We call them Earth system models. So that came much later. And of course with understanding the carbon cycle, there’s the question of how you bring a more living component into that physical part of the Earth. With the carbon cycle — plants taking up CO2, emitting it, storing it in their trunks and in soils — it became a whole new area of enquiry, which is more my focus and expertise.
The big carbon thing, what we call the carbon climate feedbacks — so what happens if we melt the permafrosts in the high latitudes, and methane and CO2 start emitting, and so on — these things didn’t really come about until the early 2000s. Basically you go from very simple representations of climate, you know, very physical, very ocean focused, very ocean-atmosphere, and then the land comes along. Land brings a lot of complexities. The ocean is a very homogeneous, if you wish, system. The land is not. You get humans doing all sorts of stuff — deforestation, reforestation, agriculture, watering, fertilising using quantities of nitrogen that are bigger than natural nitrogen production. We are superseding natural processes through chemical and industrial production. All these things are effecting climate change by producing greenhouse gases. They may not be CO2, they might be methane, nitrous oxide, but they all play a part in the bigger mix of what’s driving this human driven climate change. So much is exclusively happening on the land because that’s where humans are, but then everything gets interactive with everything else too.
Saskia: So the models are becoming more and more complex. That’s what you’re saying?
Pep: Oh, the models are just becoming a monster thing nowadays. What the models try to do, and this is very important for people to understand — the models are not just a result of a few crazy scientists who love mathematics and write crazy equations that nobody else can follow. The models try to be the best representation of our understanding. So yes, sometimes we may know a few more things than the models know. Because it takes years to keep creating a more sophisticated model to uptake new knowledge as it comes in, or new data, or satellites providing new information.
But we cannot understand the dynamics of the earth without these very complex models because there are too many processes, non-linear things that you cannot put into a simple framing of understanding. You have to say, well if you change this thing then that’s going to happen. You have to bring in all these understandings of ice, ocean, atmosphere, and land.
Saskia: That sounds like a very exciting evolution of the science, but based on a very perplexing problem.
Pep: Basically for me as a scientist, I have a background in terrestrial ecology. I moved from doing studies in the field, collecting samples, understanding how, whatever, how a landscape works in terms of nutrients and water, all the way to trying to put together an understanding of the global carbon cycle and how this thing fits into these Earth system models
Saskia: A huge shift in scale.
Pep: It has been. And not only the scales. What we are now doing has nothing to do with what we used to do, or with what I used to do. That has been super challenging, super exciting. Ultimately, the most exciting part, beyond the academic one, has been the fact that we are now able to see clearly a place where we can inform what is perhaps the single most important issue of this century — in terms of how the evolution of civilisation has become such a strong force in how the Earth works.
Climate is one thing. But we could talk about many other components such as biodiversity changes, homogenisation of the land through species invasions, through to the fact that we are now the major producers of nitrogen, which is a really important nutrient for plants to grow but it’s also very reactive in the atmosphere. It’s a significant greenhouse gas when it becomes nitrous oxide N20. Nitrogen is inert in the atmosphere but when we suck it up to produce fertilisers then it goes into the soils and reacts with water, microbes and gases. Nitrous oxide is the third most important greenhouse gas. It’s C02, methane second, then nitrous oxide. It’s produced through all the agriculture in the world.
Pep: Over fertilising, basically. What we’ve done over the years, we subsidise nitrogen fertilisation around the world to ensure that no matter how good the farmer is he or she will always get more production by dumping nitrogen. Excess nitrogen leads to all sorts of water quality problems as well as the greenhouse gases.
Moving back to why I do all this — it’s the realisation that this is a really important issue, the influence of humans on the Earth system, and that science should continue to lead with the provision of information for where we’re going and where we’re likely to go. The science can be one of the robust pillars in discussions about what to do and how to do it, which is mostly a policy and society choice, with government interventions, and ultimately the private sector being part of it. I think it is very exciting and makes the effort worthwhile.
At the same time maybe there are many scientists who have a great interest in fundamental science, in understanding for the sake of understanding this wonderful world we have. But I think repositioning our science to fully answering some of the big questions is the most exciting thing. As a young person it was clear to me that this was where I wanted to go. Not necessarily into climate science but to make the world a better place. Or you know, at least not going the wrong way!
Saskia: You’ve jumped to one of my questions. Does global change research and the way it faces such big challenges — as you’ve said this is one of the biggest challenges we’ve ever faced, culturally and socially in terms of our responsibility for the world we live in. The physical world, that is. Do these challenges change the way that scientists practice science? You can tell me if this is a cliché, but my understanding according to a western Enlightenment model is of the detached, observing scientist who’s separate from the ethical application of their findings. Maybe I’m wrong, and things have always been much more complicated than we think. But is this a new kind of science in terms of marrying the research with a form of social action or policy action?
Pep: I would say a big yes. It’s an incredible transformation. You may know there’s this Intergovernmental Panel on Climate Change, the IPCC, which started in the eighties. We’re now preparing our sixth assessment. With the first ones, scientists and particularly elite scientists, looked upon these assessments almost as something poisoning the purity of fundamental science. The people who went into these assessments at the beginning were just a few who really believed it was important. You could go around the world and say I’m contributing to the IPCC and have that downplayed. I’ve been in meetings at the Smithsonian and other institutions around the world and they said we do not fund applied sciences. Not if applied science is to understand climate and where we’re going in the future. That was in the early nineties. It’s incredible. Nowadays you’re serving as part of the panel and you’re looked upon as a great scientist doing a great thing. Scientists by the thousands submit applications to be picked. It’s a complete transformation. It has been incredible.
Pep: To me, I think there has always this issue and I don’t think it’s been dealt with very well: advocacy versus remaining neutral and detached. I think you can do detachment and I think as a wealthy society, like here in Australia, you probably need science driven purely by curiosity, as a way to understand this incredible world and where we’ve come from and our place in the universe. I truly believe that for our psyche and our evolution it’s a very important thing. But a much larger component of science has moved, and is moving, and is under pressure to move (and we talk about these things with peers) to what I call more of an informative advocacy.
That is by aligning your science with pressing societal issues and policy needs, you still can remain neutral, you still must provide the information through scientific process, meaning it’s transparent, you don’t push an agenda, it can be replicated to some extent so that people can understand what you’ve done. The conclusions must stem from the observations, from the experimentation, not necessarily from you having had a strong position on the outcome, or an advocacy that pursues an ultimate agenda either of your own or for a group of individuals. To me this distinction is fundamental.
Science is always … we talk about science, society, religion and all these things … the role of science remains important. It’s growing in importance, because of the complexity of society, the complexity of knowledge and technology, and the complexity of what humans are doing to the environment, and the speed at which we’re doing all this stuff. This moves you completely away from purely curiosity-driven science all the way to still apply the fundamental science but ask the questions that you might not pose yourself necessarily, or on your own. That is, we now sit with policy people, government people, social scientists or economists. And we may talk about a fundamental question in climate science, but that interaction helps us to pose the right question to then … you know, deploy the satellites. Deploy the modelling capability, the observations and all the analyses to say we’re really going to try to provide information that will be useful to make a decision.
A decision that of course at a policy level is very complex. It requires multiple inputs from the economy, society, where we want to go, how we want to do it, and all the pressures ultimately at the government level, but not exclusively, also at the corporate level. There are big questions about the way we want to portray or see ourselves as a society, or what we want to evolve towards. So I would say there has been a massive shift. And in a way, I feel that … I’ve lived this shift.
The shift has been palpable for the last 25 years and climate change has been one of the factors, but not the only one. Of course, there’s all the genetically modified stuff. We’re moving into a world of such opportunities but at the same time risks, meaning science has to work hand-in-hand with … or at least much closer than ever before, with society and with whichever questions are pressing. Whether we need to invest in security of food production, or whatever component of the energy system you need to consider. Mostly I work in energy systems. So, yes, a big shift.
And of course sitting at the CSIRO – the CSIRO was not created to have a bunch of people fulfilling their dreams of pure science-driven work but much more for problem-oriented or mission-oriented science. Science organisations like the CSIRO and others are more focus driven, with stakeholder involvement in defining what needs to be done.
Saskia: So it’s not just individuals working on their own. These are huge interdisciplinary collaborations. The social sciences have played a role in that for quite a while now, but less so the humanities?
Pep: We’re just touching them for the first time in the last few years.
The question of the humanities
Saskia: I noticed when Future Earth formed, that at least in writing there was a move to include the humanities. I don’t know how that played out, but it was at least an intention? How do you see the future of bringing the humanities into that big interdisciplinary mix?
Pep: Yes, you’re right. Just to be clear, the Global Carbon Project is a project of Future Earth. It just so happens that we’ve been running for fifteen years since well before Future Earth began. What Future Earth did was bring all the big players together, all the global players, and said we’re going to try to push all these lines we’re discussing. In a way, I want to say that we tried Future Earth twelve years ago and it didn’t quite succeed. We called it the Earth System Science Partnership fifteen years ago, and that’s what created the Global Carbon Project. So the GCP was already established to do all this stuff — to have the economists, the social scientists and hard core ocean modellers all together discussing not necessarily how are we going to do it together but discussing, as I said, what are the questions that we need to ask.
Then we may work a little together or we may not. We may split and go into what we’re good at in our various fields but with that common thread, which for me is the exciting thing, the common thread and of course the linkages.
Saskia: So I guess that’s the big question with the humanities: what are the linkages. There might be shared concerns. But there are also the challenges of interdisciplinarity when the fields are so different.
Pep: I just want to say up front, I am totally naïve about this stuff. But to me one of the great things about the humanities component is that we have to communicate with bigger audiences just to bring a common sense of purpose or thread. You’re clearly not going get this from Pep Canadell writing scientific papers and then writing for The Conversation, which is kind of the usual thing that the good scientists do. You know, very few scientists do that, but I spend a lot of time writing for The Conversation and other places. But I still don’t think that’s going to do it. It’s one step and it actually helps to disseminate quite a bit, there are now hundreds of thousands of readers of these articles.
But I still think we need a completely different layer where people get information or senses or feelings for what is appreciated or not, or for where we want to go as a larger humanity, what shapes the values. Where do we get all the information from about many of these things? The humanities can play a huge role in this. In a way, to me, it’s about a common discussion about all the big issues of climate change, which are really about poverty alleviation and equity. These are the fundamental things.
The reality is that in Australia we are very rich, we might lose the Great Barrier Reef, but sure we can all have air conditioning. But go around the world and there is poverty, there are 200 million people in India not even connected to the electricity grid. And now we’re going to ask them not to grow their emissions while we’ve been doing it forever. So there are all these big issues that are part of the human condition and part of how we want to see ourselves both within Australia and in the world. I don’t think scientists can shape these views at all. I think the humanities can play a huge role. That’s where I see this kind of beautiful interaction that … There are no numbers of papers we scientists can write ourselves on anything that can make … well it makes a difference in that it’s the robust science that says we have a problem.
Saskia: But where do you go with that?
Pep: Exactly. At that point it almost leaves our hands, and we’re no longer relevant. So who is relevant? The governments? I don’t know. The corporate world, which will need to invest in all these transformations, not the government, so let them just run on their own? What about the checks that we want to put in place as a society? And how do these questions get transmitted to people and the discussions opened up?
A nice unrelated thing is the Adani coalmine and Australian banks saying we’re not going to lend you money. Let’s be real. Ten years ago these guys would have given their money. Ten years ago. People have started making connections and of course it hasn’t come out of the blue, it’s come about because smart people have made the connections and shown them very clearly. They’ve said, well you can’t be hypocritical. You’re conducting all these programs on social engagement and environmental and civic stuff and then you’re just paying the investments that enable companies like Adani. Because it isn’t just the companies themselves it’s whoever is providing them money. And this connection has become a huge thing.
We talk to a lot of financial institutions around the world these days and it’s incredible. They say, on the one hand we want to make sure for our investors that we’re not investing in the wrong thing (for financial security) but we don’t think there’s any shortage either to invest in a decarbonisation pathway and full energy transformation into renewables and non-carbon energies. So these people are changing for their own sake, but also ultimately because they have clients knocking on the door saying, What are you doing investing in coal projects, what are you doing. Slowly but surely individuals are shaping bigger responses. They’re asking how we can help better and in new ways. The humanities and social sciences are part of that: how can we respond in better and unique ways.
Science of attribution
Pep: Climate science is now on the brink of a very interesting new development, stemming from fundamental science but with incredible relevance to society. Currently when a weather or climate event comes along, we say well we’ve always had El Niños, is this a little stronger because of climate change or not? Something terrible happens, the floods in Brisbane, droughts, cyclones, tornadoes, and we ask was it climate change. But because we have so much competing capacity now, the models can look at a single event, particularly if it’s a heat event and run the model let’s say from the last 100 years all the way to today when the event occurred. They can run the model with greenhouse gases and then run it again without greenhouse gases. Then they run it hundreds and hundreds of times to experiment, so much so that some scientific groups use citizen science. They ask people to connect their computers at home and run hundreds of computers as soon as a particular event has happened. The model is ready — you just have to switch off and on the greenhouse component.
Then you develop probabilities of such an event occurring with greenhouse gases or without. You can calculate whether a particular extreme — say a summer that broke all the records — had eighty per cent more chance of occurring in a greenhouse world or not. You will never be able to say that the event would not have existed at all, because that’s not how greenhouse works. It operates on top of the way the Earth already functions. Extreme events are happening all the time, it’s just that now we have extra heat on top of what already exists. But we can now tell you the probability that an event was enhanced because of greenhouse gases. This new science is called the science of attribution.
Another thing that’s begun happening over the last few years, starting in the US and also now quite a bit in Europe, there are a lot of court cases on climate change. From kids in the US to people in the Pacific Islands, they are bringing cases to court to say because of you — federal government or organisation — we’re receiving impacts because of your inaction.
With the new science of attribution, we can now from a probabilistic point of view tell you of many extremes that may cause quantifiable economic costs or losses, or death of people. This means you can go into a court and say this thing happened because there has been no action.
The reason I’m bringing these two things together here, right now, is because I think in the future we’re going to see much more of this from communities that are heavily affected nationally, globally and internationally. People will be going to an international court and saying, we Bangladeshis or we Pacific Islanders or we victims of this latest tornado, we are in our situation because the ocean had all this excess energy because of heat caused by greenhouse gases. From a scientific perspective, you can now do the attribution.
Saskia: It would be really interesting if these cases could help define a global commons, in legal terms.
Pep: Yes, yes. It’s not going to solve the problem on its own, but we’re starting to move away from saying, Well we don’t know whether it was caused by climate change or not. It’s just the wrong question. It’s not whether this thing was created by climate change. Climate change operates on top of what the Earth already does. Now we can tell you the probability that this thing was enhanced because of greenhouse gases. There are cases now everywhere. Very high-level figures are getting involved to bring them into the public perception. To me these cases could achieve what the disinvestment movement is doing for climate change, where individuals, from the bottom up, are shaping bigger responses.
1. The concept of the Anthropocene was proposed by atmospheric chemist Paul Crutzen in 2000 to capture a ‘quantitative shift in the relationship between humans and the global environment’. The term suggests that ‘the Earth is now moving out of its current geological epoch, called the Holocene and … that human activity is largely responsible for this exit from the Holocene, that is, that humankind has become a global geological force in its own right’ (see Steffen et al 2011: 843).
2. Other programs include DIVERSITAS (International Programme of Biodiversity Science, est. 1991), the International Human Dimensions Programme on Global Environmental Change (IHDP, est. 1996) and the Earth System Science Partnership (ESSP, est. 2002).
3. The IPCC recently identified the world’s carbon budget as the ‘estimated amount of carbon dioxide the world can emit while still having a likely chance of limiting global temperature rise to 2°C above pre-industrial levels. The international scientific community estimates this budget to be 1 trillion tonnes of carbon (1000 PgC). … The world is currently on track to spend the remainder of this budget in just three decades’ (World Resources Institute).
4. According to the American Geophysical Union, ‘Global Environmental Change addresses large-scale chemical, biological, geological, and physical perturbations of the Earth’s surface, ocean, land surface, and hydrological cycle with special attention to … human-caused perturbations, and their impacts on society’.
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