Arquivo de etiquetas: Transição

Antropoceno XLV- A ciência no antropoceno

Now the question  is science stepping up to this challenge? Because I would argue and many colleagues with me that the policy domain is making enormous advancement based to a very significant extent on the knowledge provided by science, but that’s been largely diagnostics. Is science now prepared to also step up in contributing solutions? And the exciting answer is yes.

There’s a lot happening in science to now step into much more interdisciplinary approaches where natural science and social sciences work together for solutions, and to engage much more in what we call co-design and co-development of knowledge, together with businesses, together with community stakeholders, together with policymakers.821

Now where does this arise from? Well it arises from science reacting on the nervousness of its own evidence. The diagnostic is now so dire that we can truly talk of a planetary crisis. And science is getting nervous sitting on this enormous amount of evidence that humanity is putting its own future at risk.

This has led to very significant movements towards engaging more from science in exploring solutions. There’s also a deep emerging recognition that the science, policy, business, particularly partnership, is beneficial also for academic research, what we call co-design and co-development. So this is quite interesting and these are key features of the moving and advancements in what I call sustainability science; the emerging field of an integrated research for sustainable development.822

Out of this comes, for example, a new initiative, the world’s largest initiative on global sustainability research where Earth system science is moving towards solutions for global sustainability. It’s called Future Earth, it is an integration and a merger of the large global environmental change programs that have been around for 30 years and that actually are the source of the bulk of insights that, for example, led us to the conclusion that we are now in the Anthropocene.

In a very important large conference a few years back called Planet Under Pressure the scientific community came together and launched the idea of Future Earth, which is now becoming a reality in 2014-2015.823

So this is a large endeavor of thousands of scientists working together across social and natural sciences to not only focus increasingly on solutions, but also to learn more about the risks we’re facing, of how the Earth system operates, improve the definitions of planetary boundaries, and work much, much more together with different stakeholders in society.

Now what will then Future Earth do? And what is science increasingly excited about doing in general? And in a very simple way to illustrate that we can say that of course this is not true for all science, but you know, the large, large thrust after all has been that the science on global environmental change has largely focused in the past on understanding how the Earth system works as a self-regulating complex system, so we’re starting to understand more and more how climate interacts with the biosphere, that tipping points occur, etc., and also how we humans impact the system, which has been tremendously important to understand the pressures we’re posing. Future Earth is about adding two social dimensions.824

One is how does it impact on our own well being and what are the implications for livelihoods and development? And of course, perhaps the most exciting, what’s the response? How can we as scientists engage in finding the pathways towards a transformation to global sustainability?

Another very important advancement that we all are so well aware of is the bridge between science and let’s say the most accessible form of knowledge for decision making, namely assessments.

So we have a very, very long engagement in climate with United Nations Intergovernmental Panel on Climate Change, which has recently released its fifth assessment, the basis upon which decisions are made on climate change. But I’d just like to remind us all that we also have the sister of the IPCC, the Intergovernmental Platform on Biodiversity and Ecosystem Services, IPBES, which is now in place to do the same type of knowledge synthesis on ecosystems and biodiversity as a support for decision making.825

And Finding Sustainable Development Solutions Network, which is a broad global platform of knowledge for change. So these are very profound large examples of how science is stepping up to the challenges in the Anthropocene.

So to conclude, initiatives like Future Earth and alliances such as the Earth League, which is another coalition of top, top knowledge institutions gathering together to serve society with better risk analysis, better understanding and solutions, is in my mind a very, very strong signal that science sees not only the risks in the trajectory and the paths we’re following today but also enormous opportunities in a transformation to a world within a safe operating space.

Antropoceno XLIII – ciência, politica e ação individual no antropoceno

We are now entering  in final module on this lecture series on Planetary Boundaries and Human Opportunities.

In the previous module, we dug ourselves into the challenges of translating our Planetary Boundaries science and challenges in the Anthropocene into global governance, the role of technology, the transitions humanity face in terms of energy, food, urban, pathways towards a future of growth and development within a safe operating space.

We looked into the challenges related to sustainable and resilient urban development and trying to position our new thinking on global sustainability within the realm of opportunity and development for humanity in the future.

Now in this eighth and final module, we’d like to integrate and synthesize and summarize all the insights across the entire set of lectures. We’d like to do that in the context of the big global policy agenda on transforming the Millennium Development Goals to Sustainable Development Goals.

We’d like to do it also by sharing the latest thinking in how science is organizing itself and also opening opportunities for young scientists and bright minds to engage in the new opportunities around not only interdisciplinary research but also research for solutions and exploring avenues towards a future within a safe operating space.

In doing so and inspired by all your inputs into the forum and personal insights, we’ve also gathered the entire team of lecturers to share with you their personal reflections and insights, originating and being inspired by the contents of the entire course and engagement with all of you during these weeks.

We’d also like to remind you that even this week, please do keep the discussions and connections and ideas lively on the forum. We still hope that we together can take this course as a starting point to engage further in the future on exploring solutions for global sustainability.

So see this week as an opportunity and a Launchpad to start a dialogue that will go way beyond the weeks that we’ve had together over the past two months.


Antropceno XLII – Reencontrar a Humanidade no mundo urbano

I look at how trade enables movement of food and feed anywhere on our planet. And I’m also the Director of Studies, so I like to teach about all the things that we do here, in an inspiring way hopefully.

More than half of the population today lives in cities. And although we are no longer an agrarian societies we are still utterly dependent on agriculture for our food. And those of us who live in cities I think are disconnected from where our food comes from and how it’s made. I think we’re actually disconnected from the entire process of agriculture.

And part of this is because of global trade. Global trade lets us urban citizens consume foods from anywhere on the globe, produced far outside the city borders. And it also enables us to never actually see what’s going on in agriculture production.761

So urban consumers are different. Right now we need to deal with this balancing act too when it comes to feeding cities and feeding us to potentially feed the future estimated 9 billion people. We need to have more food, we need to maintain livelihoods of farmers, and we need to remain within the Earth’s capacity.

So we need to produce maybe 60% more calories of food. And we need to at the same time safeguard the livelihoods of the poorest 900 million people, 70% of which are very closely tied to livestock production.

We already see a 20% decline in the number of farmers on this planet in the last 50 years. Somebody’s got to grow our food. And we can’t continue doing farming and fishing in a way that degrades the natural basis for production.762

So there’s some unique challenges in the nexus of cities and food and sustainability. Urban dwellers do not understand agriculture production. That’s the first main challenge.

Second is that urban populations are wealthier. We consume more – because I’m an urban person too – and mostly though we consume differently. That 60% of new calories that we need to get, it’s not just because there’s going be 2 billion more people on the planet, it’s because we want to eat things like meat. We eat things – we eat fruit, we eat vegetables in city. That’s different than the traditional more grains-based diet.

The third kind of unique challenge is that there’s no longer going be just local production feeding the local population. The vast majority of food production is coming from far outside the city areas.763

Fourth, we see changing values, cultural values, in the urban areas. With this highly networked kind of place that we live in in cities, this globalized world, has become more westernized. And these type of western diets are very different and they’re resource-demanding too.

And last, fifth, is that urban cities, urban areas, are engine rooms of people that drive the free market system. So when we change our diets, when we urban dwellers choose different diets, we transfer that into the market system, we’re demanding different things. And that’s a challenge.

So I looked with my colleagues at three different food systems, and I mapped these developing country kind of capital regions in Australia, in Denmark and in Japan, and to see how they had different approaches to achieving their own food security systems.764

So Canberra in Australia, Canberra can provide more food for itself, but it’s chosen – since 1965 it produces less food in its own areas. And that’s because, partially because, urban dwellers in the Canberra area, they prefer – and they’re the ones with the political power – they are the ones that prefer smaller, more pristine ecosystem-like areas, and they’re pushing actually for less agriculture production inside the Canberra area. And that means that they’re – the Canberra is having to import more food.

In Copenhagen, Copenhagen could be self-sufficient but they’ve chosen instead to not be, they’ve chosen instead to import feed inputs, to value add it, and export pork.

Japan, Tokyo, can not provide for the whole 40 million people in the city. They have really high yields, they have a very productive production system, but they can’t provide for 40 million people in the land area. But you can see that because they place a very high cultural value on the food that you can see that they actually manage to maintain very high production levels of the traditional types of pork, rice, and cabbage.

So these are three different approaches that these cities have taken, and you can see that this is how they’ve solved their food systems. So this kind of study is useful I think because cities are going to need to manage food security by learning where in the world – what agricultural ecosystems they need to support their consumption.765

And I think Japan is a good example, the example of how many cities are going to feed themselves now. They’re going to depend on very large area outside of the city limits for their food provision. But there’s another reason that you want to make sure that you know where your food is coming from. And for example in 2010 when there was a large drought you could see that the willingness of certain countries to export food, for example Australia was not as willing, and partly because they didn’t have the amount of production of milk and butter, Japan had to look elsewhere to find these sources.

In 2010 during the droughts Russia decided not to export grains to the EU and the big cities in the EU. So you need to know where your food is coming from if you’re going to manage your food security.

And thinking about planetary boundaries, food actually is affecting every single one, it plays a role in all of the nine planetary boundaries. And people talk about deforestation, tropical deforestation, and land use change, but there’s another kind of deforestation that I haven’t heard as much about, which I’ve looked at, and that is related to aquaculture. And it’s related to mangrove deforestation. For example, more than half of the mangrove areas along Thailand’s coasts have been deforested to produce jumbo shrimp aquaculture. And that consumption is driven by rich consumers in the United States and Europe.

Another specific example, which is actually maybe a good success story, where we’re seeing the ozone depletion reduced is the fact that the CFCs, the chlorofluorocarbons, were originally used for refrigeration, for food. So we were able to ship and store food, and that’s why we were using so much chlorofluorocarbons. So these are, yeah, two just specific examples of how food is tied. And there’s many examples of how food is tied to all the planetary boundaries.

I’d like to finish talking with you today and leave you on a good note. There are many good examples of some fun innovations that come from cities. Urban gardening, even though it may not be able to feed the vast majority of us, but there are some really good examples. For example is Dar es Salaam it’s estimated that maybe 90% of the vegetables are actually produced in the urban area. And that in Hanoi they’ve maybe managed to produce up to 60% of their rice, right there in the urban area. So there are some places where they are managing to produce quite a bit of food right in the urban areas.

But I’d like to finish with my own close to home example where I have a Masters student who has started a company, Bee Urban, in Stockholm, and she and her friends are putting beehives out on urban roofs all over Stockholm, and by increasing the habitat for the bees we now have pollination services throughout Stockholm, and we can maybe even say that this is improving our capability here to do urban gardening in Stockholm.

So these are just a few examples of some really exciting and fun things that are happening in cities when it comes to food production and food innovations. There are many, many different fun things going on, there are many different ideas, many different things that should be happening. We shouldn’t have one solution. There are many different ways, and many different things that we should be doing. I encourage you to find out what’s important for you, and think about what you ate for lunch, and where it came from. Thank you.

Antropoceno XLI – Caminhos da Transição: novos caminhos das cidades

What’s actually happening in the city ? When talking about the Anthropocene and about the future challenges, there are so many challenges and negative things we have to deal with. But I discovered when actually coming to the urban and the city there are also fantastic opportunities to solve these problems, and that is what really excites me.

We’re going to go through both some of the challenges because they are there, but also we’re going to particularly look at what are the opportunities here to solve some of these big problems we have had?

So talking about the challenges of course. Urban areas are expanding; more people live in cities than in rural areas in the world. And we also know that urban areas are expanding actually much faster than the urban population, and this is called urban sprawl. So we’re consuming a lot of land. And this is particularly worrisome because we’re also consuming a lot of prime agricultural land, which would then would have knockout effects on forests and savannahs and biodiversity in other areas.751

So this is something we need to deal with. But urbanization is diverse. So we have on the one hand megacities we have by now around 30 megacities in the world with a population of more than 10 million. By 2030 we will have maybe fifty. So there is a huge expansion of these really large cities. But there is also another pattern that we need to think of, and that is the most of population growth in the world the next 20 years will happen in small and medium size cities. And there’s a lot of land that’s going to be consumed when these cities expand and grow. And that we should also not forget that in this diversity of urbanization we also have shrinking cities, and particularly in eastern Europe, parts of Japan, eastern North America, we can cities that actually are shrinking, they are losing population, and we have a city-to-city migration, which also opens up opportunities when it comes to biodiversity, ecosystem services and managing land.

So some of the key challenges are looking ahead with organization is that we will need more resources for a growing population, and also that when people move into cities they become more affluent, and they will increase their consumption of red meat, for example. So the dependence on land is going to increase. And just as an example, London today is requiring an area a 125 times the size of the city. And that’s the size of the UK’s entire productive land surface. And this dependence on land is going to increase and that’s why we need to understand and manage this is a way that we could actually have a sustainable production.752

So the first point I want to make is that local governments need to address this land consumption and land management in a very active way in the future. And that’s one of the keys for sustainable development. And examples of what will happen when land is consumed is that urban areas will infringe into biodiversity hotspot areas, for example.

And just to take an example, 25% of the world’s protected area today are within 17 kilometers of a city. In 10 years it will be less than 15 kilometers. Data around this [has] been developed in a large global study called the Cities of Biodiversity Outlook, which was requested by the UN and looking at the challenges but also the opportunities. And Ban Ki-Moon writes in the preface of this study that as he viewed it the principal message is that urban areas must offer better stewardship of the ecosystems on which they rely.

And this is actually what we’re going to explore for the rest of this lecture on what are these opportunities and what does this stewardship actually mean? Because there are opportunities. Looking ahead until 2030 we could see that all the urban land we expect to have in 2030, 60% has yet to be built. There’s an enormous investment ahead of us for the next two decades in all types of infrastructure. And we need to get that investment right to get on a sustainable pathway for the planet.753

And I would argue that this is the key for a sustainable planet, that we actually get urban development into a greening path. These investments are going to be made anyway. If we turn them into a green, more sustainable direction that’s the key. And we will show you some examples.

Humans living in urban areas are dependent on clean air, on clean water, food, and many resources. And urban ecosystems, the living world of urban area could actually promote and provide some of these benefits. These are called ecosystem services that could clean the air, help clean the water, and integrating living systems with a built environment in these ways I think open up fantastic opportunities to create urban areas that are livable, healthy, and prosperous, and would actually – are providing an environment for people that they enjoy and create a rich life, but also in a sustainable way.754

So giving an example. One of the challenges we have ahead of us is of course climate change. And one of the most likely effects of climate change that would affect people is urban heat waves. We’re going to see a lot of these examples in the future where very hot temperature will prevail in cities. And just as an example the consequences of these are immense. In Europe we had a huge heat wave in 2003 and it’s estimated we had 70,000 excess deaths.

So how are we going to deal with urban heat waves? One way of doing it is actually to start planting trees in the city, because there is a very clear effect – cooling effect of trees. If you increase the canopy cover from 10 to 20% you would decrease the ambient temperature with anything between 3 and 8 degrees C, which is substantial.755

And while you’re planting a tree in the city, you’re planting many, you would also get a lot of other benefits that are related to culture, to air cleaning, to reducing peak and precipitation, all other benefits. Which we just started to value and started to understand.

So here are lots of opportunities that combining the built environment with a living environment to actually address and solve a lot of these challenges we have ahead.756

And just as an example where this is actually taking into action and implementation, Mexico City has launched a huge program where they will build 10 000 square meters of green roof to provide cooling, and regulate humidity, and also provide sites for biodiversity in Mexico City. And they also have a program for conserving land with the similar purpose of contribute to cooling the city and contribute to maintaining some of the very rich biodiversity in the city area.

And another important challenge when we look ahead is that we will have a growth of cities and a growth of population, but the average age, or the age of this growing urban population will be there will be young people. So the majority of people living in the world and in the cities in the future will be below the age of 20.

And there is a huge educational challenge here, but also opportunities. If we could find ways of engaging young people in managing, and restoring, and enjoying the living world in the urban area I think that’s one of the most fundamental keys for a sustainable pathway.

So just as an example of hundreds and hundreds of exciting projects going on around the world in cities, here’s one from New York City, in [the] Bronx where a group call themselves Rocking the Boat have engaged with disadvantaged kids in [the] Bronx and engaged them in restoring oyster banks and learning about the river, and how to clean up the river, how to create an environment in [the] Bronx that is actually beautiful which people would enjoy, and also learning about how nature actually could be an asset and something you could actually use in a very constructive, positive way to create a livable environment.

So my final message here is that cities have the unique potential to generate the innovation and governance tools that we need, and can and must take the lead in sustainable development. Most action in the world happens at the local scale. So if we could bring citizen NGOs, local governments together, with support from national governments, with support from regional government structures, like the European Union and others, and with support from the UN, I think there is so many things, so many exciting things, we could do at the local scale, where we could bring in already knowledge we have, and bring in new creativity and new thinking, new ideas to solve these problems. And I think it’s absolutely possible. It’s just that we have to come together, sit down and say we’ve got to do it. Thank you.

Antropoceno XL – Funções e Riscos das Tecnologias

This will be about technology, and this is one of my favorite topics. When we talk about the Anthropocene, I think we seldom miss the point that so much of what happens in the Anthropocene, and the fact that we might be in the Anthropocene, happens through technology; it’s been through technology. 741

And one of the favorite examples that I take up with some of my students and some of my talks is this example. A couple of years ago an NGO and a couple of researchers discovered a new monkey type in the Amazon called the Titi Monkey, a new type of Titi Monkey. And they needed money to promote conservation efforts for the monkey. So they decided to make an option, an online option to sell the naming rights of that monkey. So they did that, and it was quite successful. They managed to get $650,000, and the company that won that auction was an online casino called

So officially gets to name the monkey, so the official name of this Titi monkey is actually Titi Monkey. And it has a Latin name called Callicebus aureipalatii, which I believe means golden palace.

And it’s quite a bizarre example, of course, but I find it quite intriguing that we’re modifying – we’re affecting nature at such a deep level that we’re even auctioning out the naming rights of a monkey species to an online casino.742

I think the three interesting topics in here that are more general that this quite bizarre example. One deals of course with biodiversity and how we protect biodiversity. And there’s another issue related to politics of course. I mean where are we, is this a good idea should we really pull in private funding in this way? And giving – selling out naming rights in this way? And of course the third topic [is] about technology. Who would have thought 10 years ago that an online casino would have bought the rights to name this particular monkey?

Now I think this really brings us to an illustration of the next generation of environmental challenges in the Anthropocene, and new governance challenges facing us.

This is a quote from a New York Times article from one of the researchers a paper showing that the west Antarctica ice sheet was collapsing irreversibly, risking to create very large increases in sea level rise. And the quote from the scientist of course is, “This is really happening. It has passed the point of no return.” So it brings us back to the issue of tipping points and new risks.

Once these news were out there of course you hear discussions about trying to stop this from happening through technology, so essentially geo-engineering interventions. Sending out ships to spray out salt particles in ways that would make clouds whiter and then cool down the area, and hopefully, ideally, theoretically, cool the area down so much that you could stop the glaciers from collapsing. And of course this is just one example of many, many of these tipping point elements. This is a famous image from Tim Lenton’s work on tipping points in the Earth system.

And the issue here is of course if there are tipping points, and some of these might be a very, very large scales, and affect the Earth system as a whole, are there ways by which we can use technology to stay away from these, or mitigate these, or adapt to these in smart ways? And of course that triggers a lot of controversy and political conflict. And geo-engineering is a brilliant example of the interplay between risky tipping points, technology, and technological interventions and the political conflicts and debates those sort of discussions trigger.

And it’s not just about climate. I mean I just gave you a climate example. Some scientists propose that you would need to promote a new generation of conservation efforts that are more active to cope with climate change in ways to protect coral reefs.

So one example of tangible interventions were to create artificial coral reefs, or create big umbrellas, or to protect and cool down coral reefs, to create gene banks, etc., etc. Another interesting observation is from a workshop that was a few years ago in the UK where researchers and NGOs got together to discuss whether we can use synthetic biology to promote conservation and to maintain biodiversity. And there’s an emerging discussion about something called the extinction, so essentially using DNA from extinct species and use that DNA to bring these species back, and would that be a way to maintain and protect biodiversity?

Highly, highly controversial of course, and quite intriguing. I think one of the general reflections and reactions to this from the public and other scientists would be, but are we allowed to do this? Doesn’t this inflict on the precautionary principle? Now the precautionary principle that states that we shouldn’t do anything that might create harm. I mean that would be the popular perception of that.

But in fact if you look into international agreements, such as the Commission on Biological Diversity, it states something different. It says that, and I’m goint to quote here, “Where there is a threat of significant reduction or loss of biological diversity, lack of full scientific certainty should not be used as a reason for postponing measures to avoid or minimize such a threat.” So essentially actors, NGOs, a few researchers, used the precautionary principle as support for these sort of intervention[s].

And is that the proper framing of the precautionary principle, or should we have a more moderate interpretation of that? And what would that look like? So I think that’s just a simple illustration of the sort of challenges that tipping points, emerging technologies, get mixed up in a way that create[s] new political controversies and new governance challenges.

Antropoceno XXXIX – Caminhos de transição: a energia

For the world to develop within a safe operating space of planetary boundaries one of the grand challenges is a global transition to a renewable world energy system. This is a double challenge because it’s not only about biophysical operating within a safe operating space, it’s the recognition, shown in this graph, of the tight connection between energy use in the world and economic growth. In fact there’s a linear relationship so far between growing economies and growing energy use. And that is projected to continue, even though in [at] a slightly lower pace, up until mid this century. 741

There’s also the recognition of how our past looks like. And just check out this development of the extraordinarily rise in energy use since the great acceleration started in the mid-1950s. And what you see here is the growth of coal, and particularly oil and gas, as the predominant sources of energy.

So one simply has to recognize that if we’re seriously talking about sustainable development we can not escape the fact that we need not only energy, we will need more energy in the future if we take an ethical responsibility for the wealth of a world of 9 billion people.

The challenge, thus, is a transition into a zero coal or non-fossil fuel-based economy in the future. What may help us here is in fact not only technology advancements in renewable energy, which is remarkable, it’s also the fact that we are approaching or are at peak of many of the most cheap fossil fuel energy sources.742

And in this graph you see that already from the mid-’80s, 1980s, and onwards we have actually bypassed the point of access to cheap sources of oil. This has a risk of course of a transition to other cheap but even more polluting sources, such as coal, and the transition we’re seeing today in terms of fracking for natural gas, which is methane, which is a very powerful greenhouse gas. But overall it shows that however you twist and turn the analysis the era of cheap oil is behind us, which may help us also as an incentive to a transition to renewable energy systems.

But a very important challenge in terms of this transition is to recognize that not only is there a linear relationship between economic growth and energy use, what has enabled our quick economic growth is that energy has been cheap. And if you look at a key parameter in this regard called energy return on investment, meaning how much value do you get out for each input of investment into your extraction of energy.743

We have been privileged, in fact enormously privileged, of having a very large return on investments on oil over the oil era, since the early 1930s and ’40s with energy returns on investment often exceeding hundred in the early days of the oil bonanza, and today moving down quickly to levels of 30 to 15.

But look at what happens with, for example, nuclear energy, biomass, photovoltaics, oil sands, with energy returns on investment being very low. And in fact this really worries scientists and analysts because we’re not even sure how to operate a world economy with energy returns on investments going below 10 to 15, so another reason to really explore innovative solutions in the space of renewable energy systems.

And just look at this trajectory into the future indicating that we’re moving increasingly towards a point where we bypass this magical level of energy returns of investments below 10, which again means that energy becomes so expensive that it may no longer contribute to the economic growth we’ve seen in the past.744

So these are sharp reminders that the planetary boundary analysis showing the necessity to stay within a sustainable global carbon budget is coupled to the recognition also that the polluting, dirty and climate-destroying energy systems we have today are also becoming less attractive because they’re becoming more and more expensive, and less and less efficient in delivering to the human endeavor of economic growth.

Now if you look into the future the drama is equally stark. This is an analysis from the Global Energy Assessment showing that even in a transition to a sustainable energy future, here illustrated by the label Global Energy Assessment efficiency, or the Global Energy Assessment mix, which if you look carefully shows a very rapid rise in renewable energy systems and a contraction in the use of particularly oil and coal, but still the overall picture is growth of energy demand in the world.

So in 2050 the estimate, as you see even if we have very high optimistic projections on energy efficiency, we’re still seeing a future where we’re moving from our current use of roughly 500 exajoules of energy to a future of 600, 700, 800 exajoules of energy in the future. So a reminder again of the enormous challenge.745

Now what’s the solution to this? Well, most analysts would agree today that the long-term future is a future world basically or predominantly supplied from solar energy systems. We’re not there yet, but look at these graphs, which originate from fantastic work among energy researchers at Chalmers University in Sweden, showing the exponential rise in photovoltaics and wind power in key countries in the world.

And what you see here is that up until 2002-2003, we had a very slow rise in technology and uptake of these renewable energy systems. And then we have a takeoff and exponential rise where for example today countries like Germany, after all the world’s fourth largest economy in the world, if you wake up a Saturday morning in Germany you’re likely to get in the order of 30-40% percent of your electricity from wind and sun. So we’re starting to see solar and wind systems coming to scale also in the large economies of the world.

So there’s promise that this transition is not only necessary, but in fact possible to achieve at economically competitive rates, but also desirable. because they provide clean energy systems with very high benefits for health and also interestingly in a much more democratic way.746

Many of these energy systems are provided from small-scale distributed households, farms, small businesses, that produce their own energy and buy and sell energy to a flexible energy market. That’s why, to close, I believe that journals like The Economist even put at the front page of one of their recent issues a dinosaur and an oil pump in their hands, making the analysis that in fact those who invest and keep investing in dirty, risky, undemocratic fossil energy sources are the dinosaurs in terms of meeting the demands and needs and opportunities in the future. While a transition in terms of energy in a safe operating space can be, should be, and must be the opportunity for a much more clean, modern energy system for a world that of course will demand more energy to truly achieve sustainable development, but which needs to be sustainable.

7.4.2.. The role and risks of technology in the anthropocene

This will be about technology, and this is one of my favorite topics. When we talk about the Anthropocene, I think we seldom miss the point that so much of what happens in the Anthropocene, and the fact that we might be in the Anthropocene, happens through technology; it’s been through technology.

And one of the favorite examples that I take up with some of my students and some of my talks is this example. A couple of years ago an NGO and a couple of researchers discovered a new monkey type in the Amazon called the Titi Monkey, a new type of Titi Monkey. And they needed money to promote conservation efforts for the monkey. So they decided to make an option, an online option to sell the naming rights of that monkey. So they did that, and it was quite successful. They managed to get $650,000, and the company that won that auction was an online casino called

So officially gets to name the monkey, so the official name of this Titi monkey is actually Titi Monkey. And it has a Latin name called Callicebus aureipalatii, which I believe means golden palace.

And it’s quite a bizarre example, of course, but I find it quite intriguing that we’re modifying – we’re affecting nature at such a deep level that we’re even auctioning out the naming rights of a monkey species to an online casino.

I think the three interesting topics in here that are more general that this quite bizarre example. One deals of course with biodiversity and how we protect biodiversity. And there’s another issue related to politics of course. I mean where are we, is this a good idea should we really pull in private funding in this way? And giving – selling out naming rights in this way? And of course the third topic [is] about technology. Who would have thought 10 years ago that an online casino would have bought the rights to name this particular monkey?

Now I think this really brings us to an illustration of the next generation of environmental challenges in the Anthropocene, and new governance challenges facing us.

This is a quote from a New York Times article from one of the researchers a paper showing that the west Antarctica ice sheet was collapsing irreversibly, risking to create very large increases in sea level rise. And the quote from the scientist of course is, “This is really happening. It has passed the point of no return.” So it brings us back to the issue of tipping points and new risks.

Once these news were out there of course you hear discussions about trying to stop this from happening through technology, so essentially geo-engineering interventions. Sending out ships to spray out salt particles in ways that would make clouds whiter and then cool down the area, and hopefully, ideally, theoretically, cool the area down so much that you could stop the glaciers from collapsing. And of course this is just one example of many, many of these tipping point elements. This is a famous image from Tim Lenton’s work on tipping points in the Earth system.

And the issue here is of course if there are tipping points, and some of these might be a very, very large scales, and affect the Earth system as a whole, are there ways by which we can use technology to stay away from these, or mitigate these, or adapt to these in smart ways? And of course that triggers a lot of controversy and political conflict. And geo-engineering is a brilliant example of the interplay between risky tipping points, technology, and technological interventions and the political conflicts and debates those sort of discussions trigger.

And it’s not just about climate. I mean I just gave you a climate example. Some scientists propose that you would need to promote a new generation of conservation efforts that are more active to cope with climate change in ways to protect coral reefs.

So one example of tangible interventions were to create artificial coral reefs, or create big umbrellas, or to protect and cool down coral reefs, to create gene banks, etc., etc. Another interesting observation is from a workshop that was a few years ago in the UK where researchers and NGOs got together to discuss whether we can use synthetic biology to promote conservation and to maintain biodiversity. And there’s an emerging discussion about something called the extinction, so essentially using DNA from extinct species and use that DNA to bring these species back, and would that be a way to maintain and protect biodiversity?

Highly, highly controversial of course, and quite intriguing. I think one of the general reflections and reactions to this from the public and other scientists would be, but are we allowed to do this? Doesn’t this inflict on the precautionary principle? Now the precautionary principle that states that we shouldn’t do anything that might create harm. I mean that would be the popular perception of that.

But in fact if you look into international agreements, such as the Commission on Biological Diversity, it states something different. It says that, and I’m goint to quote here, “Where there is a threat of significant reduction or loss of biological diversity, lack of full scientific certainty should not be used as a reason for postponing measures to avoid or minimize such a threat.” So essentially actors, NGOs, a few researchers, used the precautionary principle as support for these sort of intervention[s].

And is that the proper framing of the precautionary principle, or should we have a more moderate interpretation of that? And what would that look like? So I think that’s just a simple illustration of the sort of challenges that tipping points, emerging technologies, get mixed up in a way that create[s] new political controversies and new governance challenges.

Antropoceno XXIX – Sintese sobre Fronteiras do Planeta

Synthesis and progress on planetary boundaries

The science on planetary boundaries builds on the remarkable advancements in Earth system science over the past 20 to 30 years. It’s an integration in the natural next step in scientific advancement between our understanding of the pressures of the Earth system, how the Earth system is a complex self-regulating biogeochemical physical system, and the recognition that if we push environmental systems too far, we risk crossing tipping point that can fundamentally, abruptly, and irreversibly push ourselves away of the stable desired state of planet Earth.561

What may surprise you is that the approach of finding planetary boundaries is illustrated very nicely in this first slide here where a Moon lander is looking at our wonderful, small, little marble Earth planet from a distance.

In fact, that’s how the analysis starts. We step out as humanity and try to understand the Earth system and ask ourselves to question what are the Earth system processes that regulate the stability and the resilience of the Earth system? And for each such process we ask ourselves what is the boundary beyond which the system could be pushed outside of a desired state?

And science shows very clearly that we know what this desired state is. And in this slide as a synthesis of that shows the ice core data from Greenland indicating the enormously jumpy ride that humanity has had throughout his entire period on Earth as modern human beings.562

This graph shows our last 100 000 years journey on Earth, until we enter the final, last interglacial period, which we learned in school to call the Holocene, which I would call the Eden’s Garden, the perfect paradise, desired conditions for us to build our civilizations and the modern world as we know it.

So the planetary boundary framework is about safeguarding the desired Holocene-like state on Earth by recognizing this state as the only state we know that can support the modern world as we know it, and from science determining the Earth system processes that regulate this state.563

And that is what led us to defining the nine Earth system processes that we know, with the best science at hand, regulates the stability of the Earth system.

And here we have of course the big systems with large scale tipping points, such as: climate change, ocean acidification, stratospheric ozone depletion. We have the four slow variables that operate under the hood of the Earth system regulating the ability of the large systems to be stable: land system change, fresh water use, the rate of biodiversity loss, and the way we interfere with the large nutrient cycles of nitrogen and phosphorus. And then we have the two processes that are so highl564y manmade: namely aerosol loading, which is all the soot and the particles in the atmosphere that cause large health challenges but also influences, for example, rainfall patterns and weather conditions; but finally of course the novel entities, the exponential growth of chemical compounds that aggregate themselves in the Earth system.

By tapping on the best science we can put quantitative boundaries that gives us in green a safe operating place. This is where we can put humanity back, to prosper, develop, evolve, and thrive within this safe operating space. That’s why planetary boundaries is a truly integrated analysis. It’s about a safe space, and by biophysical terms, but it’s about recognizing equity, fairness, and a just distribution of the remaining ecological space on Earth to enable a world of soon 9 billion people to develop and prosper.565

In my mind this is the new definition of sustainable development. It’s recognizing that global sustainability and development within a safe operating space is the new endeavor and the new goal for human development on Earth.

We’re very excited by the fact that science can now step up to, I would argue, the responsibility of providing quantitative global environmental goals of this kind. It shows in our analysis that we’re already in a danger zone on climate change, biodiversity loss, and interference with the nutrient cycles.566

This work was released the first time in 2009, and has since then led to a very large, vast set of scientific efforts of critically analyzing the quantifications, critically asking the questions whether we’ve got the nine boundaries right, and based on all the science we are working continuously updating this concept to get the absolutely best quantifications.

And a few exciting updates have occurred based on scientific colleagues around the world publishing updated work in this area. The first one is the recognition that the nine boundaries are not entirely, so to say, even in the role of regulating Earth resilience.

In fact we do identify now that three of the boundaries are what we call core boundaries. They operate and regulate the entire Earth system, and they are the endpoint depending upon how the other boundaries operate.567

So the best example of these three core boundaries is climate change. Climate change is the end result of how we manage fresh water, nitrogen, phosphorus, land, biodiversity, oceans. It all aggregates up into the functioning of the climate system. So when we use climate forcing as a good control variable for the climate system, the level of that forcing, whether or not we stay within the boundary, depends intimately whether we’re able to stay within a safe operating space for the other boundaries, to the extent, in fact, that among us scientific colleagues we talk of the boundaries as being like three musketeers, “One for all, all for one.” It seems we need to stay within a safe operating space for every boundary in order to avoid that one boundary flips over across the threshold.

The other core boundary is biodiversity. We now recognize increasingly that the genetic diversity on Earth, and the functions they play to sustain resilience and to build human well being, is a high level aggregate result of how we manage fresh water, land, oceans, nutrients, and even the climate system.568

And the third core boundary we believe is novel entities. The reason for this is that chemicals, such as everything from endocrine disruptors, persistent organic polluters, all the way to nuclear waste and loading of heavy metals, is so totally lien to the operations of the Earth system, in fact the Earth system has never seen, at least not in millions of years, the kind of human-induced artificial loading of new totally artificial compounds into the Earth system.

We’re learning as we speak what the aggregate effect of these can be on our own health, on the genetic composition of species, from birds to humans. But this is an entity of its own core right. And these three we call core boundaries.

The second development is that we’ve refined the biodiversity boundary. We call it now biosphere integrity, because we recognize that genetic diversity is one thing which we captured in the first analysis. Basically what’s the number of species on Earth, which we can measure quite well with extinction rate, which you used in the original analysis.

Now we’re much more, let’s say, sophisticated in using a new index called the biosphere integrity index, which measures not only number of species but also their functions and how many species within each function. So we can secure, for example, that we do have the minimum amount of pollinators in an agricultural landscape. And this is truly exciting giving the tools for sustainable development in the Anthropocene.

We’ve also refined some of the quantifications. And I would just like to share a few of the key developments here. And the number one is on phosphorus. In the original analysis, we were preoccupied with how much phosphorus can we load into the oceans before we risk a large scale tipping point in the oceans into anoxic, oxygen-free dead states in the ocean?

We were criticized for this. Scientists pointed out that way before you’ve pumped in so much phosphorus in the ocean that you could tip the ocean you’ve destroyed so many fresh water systems along the way of the journey of phosphorus from where it’s loaded, often in an agricultural field, to the ocean that we have tipping points occurring in fresh water systems. So now we actually have a twin definition of the phosphorus boundary.

One, which we maintained from the original analysis, which is the amount of phosphorus that we can load in the oceans. It emains in fact eleven million tons of phosphorus per year. We’re today loading eight, nine so we’re approaching the boundary. But can you imagine? The analysis shows that already at averaging at 4 million tons of phosphorus per year on what we call erodible soil, which is essentially how much phosphorus we can load on productive agricultural land, when we go beyond that number we risk large scale tipping points in fresh water systems. These twin boundaries need to be considered for phosphorus.

For nitrogen finally we took, which was a very wise decision, the valve of how much inactive nitrogen we can maximum take out of the atmosphere, and transform into reactive nitrogen which would plug into the biosphere. You may be aware that the fantastic invention of the Haber Bosch process, which produces reactive nitrogen fertilizers is the vehicle for our modern agriculture, without which we probably could not feed ourselves in the modern world. But it loads reactive nitrogen into the biosphere at an extent, which is so large that we humans are now a much larger force than the entire global natural nitrogen cycle.

We estimated in the first analysis that the maximum loading of nitrogen in order to avoid that nitrogen triggers tipping points in ecosystems was 35 million tons of nitrogen per year. It was a first best guess. Roughly one-fifth of the amount of nitrogen that we’re taking out of the atmosphere, so a dramatic decrease, and therefore indicating that we’re way out in a danger zone on nitrogen.

However, we did, you could argue, a simplification in the first analysis, because you see there’s another way that we humans take out nitrogen from the atmosphere, which is by cultivating nitrogen-fixating crops. So, we have also biological fixation nitrogen actively induced by us humans in modern agriculture. Now we have included that, so now we have a boundary that includes both the industrial uptake of nitrogen from the atmosphere in the industrial production of fertilizers, and the additional human-induced nitrogen fixation by, for example, legumes in modern agriculture. And together that forms a much more robust boundary, which ends up being an estimated 44 million tons of nitrogen as a maximum boundary per year.

I won’t go through the rest of the boundaries. I really urge you to look at the analysis and the materials that come with this lecture. But I really want to close by emphasizing that every boundary has an uncertainty range. And the uncertainty range is often quite large. It’s the humble reminder that science continuously adds new knowledge, and that the boundary position is proposed at the lower, more precautious end of that uncertainty range, because we now, as for ozone, that we always are facing surprise when it comes to the large changes we’re seeing in the Anthropocene.

Overall it’s also important to recognize that even though we have attempted to quantify boundaries for the nine boundary processes at the global level, they do operate across scales, and they do interact across scales.  We’ve done some very significant updates in terms of downscaling those boundaries that are relevant to downscale, and these include, for example, the coupling of a global boundary, on fresh water with the river basin definition of minimum amounts of environmental water flows.568

The coupling of the phosphorus boundary for fresh water, with a maximum amount of phosphorus per hectare of land that we can allow ourselves to apply. Same for nitrogen, taking it down to the hectare level.

These are really exciting developments which enable the planetary boundary concept to be operational also at the local level, for a business, of a community, or of a nation’s policies in terms of how to contribute to stay within a safe operating space. And that is in my mind one of the biggest advancements in the work we’ve done in the planetary boundary analysis over the past five years.

Antropoceno XXVIII – As novas fronteiras

Novel entities

Hello, my name is Sarah Cornell and I’m an environmental researcher at the Stockholm Resilience Centre. The first thing I need to do right now is explain what I mean by the term novel entities. Back in 2009, Johan Rockstrom and colleagues argued that there should be a planetary boundary for chemical pollution. But they weren’t able to define a quantitative value for that boundary.551

In recent years this challenge has been a topic
of a lot of conversation between Earth system scientists, my own field of research, and ecotoxicologists, people who deal with the problems of chemical pollution.

We now refer to the process as the release of novel entities into the environment. Why did we change the name? Well, first of all it signals that we’re focused on the role of human-caused changes in the Earth system that can fundamentally alter the way that biogeochemical, ecological and physical processes happen at the global level.

The changes we’re concerned about are the ones where human technological capability lets us bypass the normal ecological and physical self-correcting, co-evolutionary behavior of living organisms interacting with the physical processes of the planet.552

When I talk about self-correcting behavior I simply mean that the toxic substances that exist in nature generally break down in nature. To give a really blunt example, an organism will die if it’s exposed to natural toxic substances, but natural processes will also tend to break down and disperse the toxin in question. And there are many chemicals that have toxic effects, some of them like salt, or alcohol, or kerosene, or snake venom can be very toxic indeed, but they are dissipated in the environment because living organisms have co-evolved with the processes, the chemical processes, that produce them.553

Our human technical capability lets us put together chemical substances in combinations that did not exist before, and that no ecosystem has been adapted to, or can adapt to, on the time scales that we see for technological change.

Chemical toxicity on its own isn’t necessarily the problem, it isn’t a systemic or planetary problem. Life can and does adapt to toxic substances. And we don’t need a planetary boundary for issues that are local and temporary.


We’re concerned about Earth system processes. So for that reason the term chemical pollution was too general for our purposes. But we do need to be aware of the planetary risks of creating these fundamentally novel substances that can’t be metabolized, that don’t break down easily in the environment, and that interfere with the physical and ecological processes on which all of the other Earth system functioning depends.

We’re concerned about humanity’s capacity to mobilize some natural toxic substances in new ways, in new forms, and in an ever-accelerating rate. The most obvious category of novel pollutants is the completely new synthetic substances. We can’t say that there’s a Holocene background level for these kinds of compounds. Compounds like persistent organic pollutants for instance, often called POPs.555

Another Earth system problem is the production and the environmental release of highly reactive molecules that contain some of the toxic or radioactive heavy metals. These organic compounds can be transported through water and the atmosphere to some of the most remote parts of the Earth system. Mercury is one very concrete example. Volatile organomercury compounds are emitted into the atmosphere and they can be transported and they expose ecosystems, and human populations, to very high levels of pollution very far away from their original sources.

Here we have a few other examples where Earth system functioning has already been impacted by human technological capability to produce new chemical substances. They’ve all had serious, if not necessarily catastrophic yet, impacts. You’re probably familiar with the problem of the chlorofluorocarbons, the CFCs, that led to the depletion of atmospheric ozone in the upper layers of the atmosphere.

They’re also powerful long-lived greenhouse gases, so in that sense they’re chemical substances that interfere with the physical functioning of the Earth system.

Another very well known example is the problem of DDT, a synthetic pesticide that kills agricultural pests and mosquitoes, but many other organisms too. DDT accumulates in fatty tissues and so it can be carried through the food chain. It persists for years in soils and sediments. It has now become a globally distributed problem and it has fundamentally changed the way that ecological processes happen in the Earth system.

As a result of planetary experiments like these we know that particular traits make novel entities a problem in the Earth system. Toxicity is important but we must take a big picture view that goes beyond just the effects on individual organisms through to ecosystems and actually the whole planet. Problem substances persist in the environment. This means that they can be transported large distances around the world, either in living organisms or through water in the atmosphere. We see systemic effects when these substances accumulate in living tissue. For instance, the problem of bioaccumulation makes substances become more concentrated as you work up the food chain. So, some of our keystone species in ecosystems are the ones that are most vulnerable.

Another important trait in this is the very high risk of irreversibility. Sometimes this is just because a problem has become globally distributed and we can’t deal with it directly, but in other ways it’s because we have passed a physical or an ecological tipping point in the way that the Earth system functions.

All of this means that we are still no closer practically to achieving a single quantitative boundary value for chemical pollution or these other novel entities. A major practical obstacle is the sheer variety of chemical substances, of radioactive substances, and of the many forms that these substances take once they’ve been released into the environment and are subject to chemical and biological changes.

Because of this colleagues at Stockholm University, and many places around the world, are working on defining principles that will let us identify planetary risks associated with the creation of these novel entities and their release into the environment.

We really want to improve the way that we screen for hazards, and the way that we manage and monitor environmental changes caused by novel and synthetic substances in the environment. One of the big implications of this is that we simply must halt the environmental release of the most problematic substances.

556The big challenge is we don’t know which those substances are usually until it’s too late and the impacts are already seen in the environment. So this also means that we must apply the precautionary principle much better.

The risks of environmental change are not known very often with some of the compounds that we’re creating, and certainly with many of the compounds and technologies that we’re capable of creating. We, here at SRC, and in many of our global change partner organizations, [are] encouraging dialogue about this new area of research.

It requires new interactions between science, and policy, and business, and actually between everybody in society, because we’re all exposed to these new global risks and we need to deal with them together.

Antropoceno XXVII – A fronteira dos aerosóis

Aerosol loading

Hello, I’m Sarah Cornell from the Stockholm Resilience Centre. And I’m going to explain why we’re concerned about the global human impact on atmospheric aerosols.

Aerosol is a rather technical term to describe the phenomenon of liquid droplets or particles, very small particles, that are held suspended in the atmosphere. Aerosols play many very important roles in the atmosphere and in the Earth system.541

They can both absorb and reflect light, so they’re important in Earth’s heat balance, and in the climate system. They provide condensation nucleus points; water condenses on aerosol particles and affects where clouds are formed and where rainfall happens. And they also provide microsurfaces for chemical reactions in the atmosphere. So, they influence atmospheric chemistry. For example, the reactions leading to stratospheric ozone depletion, or the ozone hole, happened on polar clouds that formed on stratospheric aerosols in the upper atmosphere.

To understand atmospheric aerosols, and the additional loading that humans are creating, we take physical and chemical measurements of gases, of particles, and of rainfall. A lot of this work is done in particular locations in different ecosystems, especially in urban ecosystems where the particulate loading is highest. But we can also measure aerosols from space.542

Aerosols can be emitted directly into the atmosphere and they can also be formed through chemical processes in the atmosphere. That’s what we call secondary aerosol. One of the main natural sources of aerosol is actually the world’s oceans, waves and bubble bursting eject saltwater directly into the air and the water evaporates and leaves little microcrystals of salt. Other natural primary sources include fire, volcanoes, and air-blown dust.

There are natural sources for secondary aerosol too. For example, plankton and land vegetation emit organic compounds that react in the atmosphere to make very small particles. These reactions that create aerosols that affect the distribution of clouds over forests and coastal zones.

We also see human impacts in both direct and secondary aerosols. Land use change and combustion processes change the global patterns of dust and smoke emission. And together with transport and industrial processes we are currently changing the emissions of a very large number of chemical precursor gases that become aerosols in the atmosphere.543

You’re probably familiar with some aerosol systems already. Smoke is a suspension of carbon particles in the air; fog is a suspension of water droplets; and the gas emissions associated with human activities, interact with each other and with these natural systems, creating really much more complex aerosol systems like smog and photochemical haze.

In the last century killer smogs, or pea soupers, were a severe environmental problem, so industrial smoke emissions are very tightly controlled in many cities of the world. But however industrial and urban emissions are still the cause of many problem aerosols in other parts of the world.

Photochemical haze plagues cities like Shanghai and Los Angeles and many other mega-cities in the world.

These aerosol systems are complex. They involve both natural and anthropogenic sources, they involve many different kinds of chemical substances, they involve direct emissions and reactions that happen in the atmosphere, and these reactions involve solids, and liquids, and gases. In other words, the composition and the ultimate fate of aerosols depend on many different geographic and meteorological conditions.

This presents a major challenge to us when we’re trying to find a global measure for what is acceptable or not acceptable in terms of aerosol changes in the Earth system. On top of that the world’s ecosystems on land and in the oceans have evolved and adapted to the biogeochemical flows that aerosols provide.

The human impact isn’t just as simple as an increase in aerosol loading. In some instances human activities are removing or relocating aerosols. We risk setting off physical and ecological tipping points when we change atmospheric chemistry in this way. This animation shows the global patterns and total aerosol loading of the atmosphere. It’s clear that aerosols are a vital part of the Earth system, and a dynamic part, and also that there’s a huge amount of variability in their local and regional patterns.

This figure is from the Intergovernmental Panel on Climate Change, and it shows the complex effect of atmospheric precursor gases in the top of the red box, and aerosols in the lower part of the red box. It shows the effects of aerosols and gases on Earth’s radiative balance. Some have a positive effect on radiative forcing, leading to warming of the atmosphere; and others have a negative forcing, in other words they lead to cooling. The net global effect is a cooling, at the moment.

The climate planetary boundary already addresses the radiative forcing effect of aerosols. But there are good reasons to address anthropogenic aerosol directly in the planetary boundaries concept, in ways that address their physical and biogeochemical impacts, not just their effects on the global energy balance.

In this context it’s really important to recognize the regional complexity of aerosols. One example where humans are causing regime shifts that might affect the whole Earth system is the change to the Asian monsoon system caused by the intense brown cloud of atmospheric pollution over south Asia and the Indian Ocean.

Another is the change in tropical rainfall patterns caused when deforestation reduces the natural aerosol emissions from trees and its interaction with the water cycle. This change can trigger climatic and water cycle feedbacks that would accelerate regime shifts or tipping points from forest to grasslands.

And yet another example that can trigger climate and ecosystem feedbacks is the deposition of dark aerosol particles, soot, or black carbon, on ice sheets and glaciers, accelerating their melting.

These kinds of pollution changes affect the regional albedo, and result in shifts in weather patterns, and biogeochemical flows, and ecosystems and the biodiversity within them.

In summary, although there is no single value for a planetary boundary that incorporates all kinds of aerosols all around the world, there’s a very strong case for specific sub-boundaries to be defined for particular aerosol systems in order to maintain the functioning of global earth system processes.

Antropoceno XXVI – A fronteira do ciclo do Fósforo e do Nitrógeneo

Interference with global n and p cycles

I’m going to talk with you about human impacts on the global nitrogen and phosphorus cycles.

The global biogeochemical cycles link the living and the non-living parts of the Earth system. Chemical relationships control the general patterns of interaction between geological and biological processes. It’s the way that the nutrient elements flow through land, ocean and atmosphere that ultimately regulate all of life on the planet. And human activities are changing all of these basic cycles.531

As we explore this topic, I’ll make reference to very simplified diagrams like this one, that show the present day cycles and the human changes. The arrows just show the overall annual flows of the elements between the Earth’s crust, atmosphere, oceans and the biosphere, that is all the living organisms on Earth.

It’s important to keep in mind that these flows are the result of many different Earth system processes, and at the same time it’s also important to remember that in the boxes, atmosphere, ocean, biosphere, and so on, we see many processes and feedbacks happening all the time. The Earth system is a very dynamic system, and the simple diagram is a very simple representation.539

Because all of these boxes are connected to each other through these different processes, human activities in one will play out in all of the others. It’s these consequences that mean that we need a planetary boundary for nutrient elements.

Piecing together the global budgets, in other words putting the numbers on the up and down arrows in those diagrams, is one of the major achievements of the last 50 years. It takes international and interdisciplinary research, and it involves scientists working in all kinds of environments around the world.538a

People are most familiar with the global carbon cycle because changes in carbon are so tightly linked to the climate system. The figure shows some of the processes that are happening at the moment. And here is the first of the simple flow diagrams I talked about.

The numbers show the annual flows between the different stocks of carbon in the Earth system, and the red arrow shows the human disturbance. Every year the biggest single change that we make to the carbon cycle is that we’re moving carbon from underground fossil fuel stocks into the atmosphere.538

We also contribute carbon dioxide into the atmosphere through deforestation and agriculture. But our main concern is that this carbon dioxide is accumulating in the atmosphere where it acts as a greenhouse gas. Climate is changing as the concentration increases.

But carbon isn’t the only element that we’re changing. People are much less familiar with the other elemental cycles, but they’re just as important, and actually they’re tightly linked to carbon and the climate system too.537

In this picture you can see the main changes in the nitrogen cycle. Nitrogen is one of the essential elements that sustains all of life on Earth. We use it in our proteins that make up our muscles, for example. The flow diagram shows the natural changes in white and the red arrows show the major changes that humans are causing in the system. The biggest change is the transformation of atmospheric nitrogen into reactive forms, like nitrate and ammonia. We do this because we need that nitrogen as fertilizer for the food production.

We also fix nitrogen from the atmosphere through many other processes, industrial processes and transport as well.536

Right now the red arrow of nitrogen fixation is bigger than the natural arrow of natural biogenic fixation of nitrogen. We are currently more than doubling the natural rate of drawing down of nitrogen from the atmosphere into the biosphere, but you can see that that isn’t all that we’re doing. This nitrogen is not all taken up by crops. A large amount is being released back into the atmosphere where it causes air 535pollution problems and acid rain, and is a climate greenhouse gas, and the rest is released into rivers and oceans where we have problems of nitrogen enrichment and eutrophication. I’ll explain what that is in a little while.

This is happening all around the world. When rivers, lakes, and coastal zones have very high concentrations of nitrogen, and other nutrient elements, the most responsive organisms draw up this nutrient most quickly. We end up with algal blooms, microorganisms are thriving in these water conditions.534

The image shows areas where there are very large amounts of marine algae, reflecting the highest concentrations of nutrient elements.

In the nitrogen cycle we have another particular challenge, which is that a large amount of the nitrogen is transported all around the world, very large distances, in the atmosphere. We see biogeochemical and ecological tipping points in area far away from the most intense sources. The densely populated areas have the most intense nitrogen pollution problems, but you can see from the figure that in this century of industrial activity, nitrogen really has become a global problem.533

The issue is not just a regional one. And nitrogen is not the only element that’s causing us concern at the moment. The phosphorus cycle is also being changed very substantially by human activity, and phosphorus is another one of these essential nutrient elements.

The figure again shows the processes that are happening in the Earth system, and the simple diagram shows the natural flows in white and the major human perturbation in red. Unlike nitrogen and carbon, phosphorus isn’t really affecting the atmosphere. The biggest change is that human activities are mining it from the ground and applying it to land surfaces for agriculture, 25 million tons a year. But a large amount of this phosphorus is being mobilized in the Earth system through the watercourses. It goes into our rivers and receiving oceans. It also 532contributes to nutrient enrichment. Nutrient enrichment doesn’t really sound like a problem, but it is a very serious one. Locally it’s a major problem for public health and environment, and it’s an economic issue as well.

In nutrient-enriched water systems biodiversity typically decreases. And when the algal blooms die and rot away they starve the water of oxygen. We end up with dead zones, and this is another example of tipping points that we see in the environment. It’s the risk of large and irreversible dead zones in the oceans that really calls for a planetary boundary for phosphorus.

The changes in both the nitrogen and phosphorus cycles are largely driven by the same human activity. In other words, fertilizer application for food production. The global impact arises from regional activities, so a really major area for research and policy at the moment is to improve the global assessment of both these nutrient elements.

The planetary boundaries for human interference in the global nutrient cycles now reflect these regional differences. The ecological impacts of the eutrophication of surface waters, and increasingly we’re working on trying to improve the links between the elemental cycles because they’re linked in nature.531


Antropoceno XXV – A Fronteira do Terra e da Água

Land and water use change

In this lecture we’ll go through two of the slow variables constituting critical planetary boundaries that regulate under the hood of the Earth system the big climate system and the large operation of the global hydrological cycle and how biodiversity can operate in our living biosphere, in land and water.


And we’ll start with land. Can you imagine? Over just the last 150 years we have rapidly moved into a situation where we’ve transformed almost 40% of the world’s land area into urban regions and predominantly agriculture.

And this enormous transition is illustrated through this series of maps showing the development over the last decades. Now for land use the absolute critical issue to recognize is that what determines the ability of land areas to regulate fresh water, regulate flows of different nutrients, be habitats for biodiversity, and regulate fresh water flows, is what kind of ecosystems we have.

And what we’re finding is that the number one biome system to regulate the stability of the Earth system is our forest systems. And in the original planetary boundary analysis we used a proxy to define and safeguard the critical forest areas in the world, namely what was the maximum amount of cropland that we could allow ourselves, because cropland is the largest human-caused land use change on Earth.522

And we used it because we have good data on cropland extent and cropland change. Now in the updates that we’re doing we’re focusing much more on what you see on this slide, namely directly analyzing how much of the different critical forest systems do we need to regulate the Holocene stability on planet Earth.

And we’re finding from science that the rainforests in the world, the temperate forests, and the boreal forests are the most critical ones in regulating Earth resilience. Now we are so rapidly changing forest systems in the world.523

One very dramatic example is shown here from Borneo, where almost, or a bit more than fifty percent of rainforests have been cut down so far in order to transform land use to large scale palm oil plantations. And you see in this graph the transition of the growth of palm oil and the reduction in rainforest. And this has dramatic effects for local biodiversity, devastating effect for local indigenous communities, but it also directly affects the entire regulation of the climate system and the regional patterns of rainfall across vast areas. So these are truly regulating functions at the planetary scale. And we only have three remaining rainforest areas: the Indonesian, southeast Asian, the Congo Basin in Africa, and the Amazon rainforest in Latin America.

Now the question one asks is do these shifts associate themselves with tipping points? And evidence suggests that the answer to this question is yes. Very rarely or ever in isolation, but land use change can together with changes in fresh water use trigger large scale abrupt and even irreversible shifts; what we call tipping points.

When you change land use we can have so large [a] shift in fresh water flows that it could actually induce tipping points, meaning for example when we cut down forests, take out fresh water in river basins, that we could have permanent tipping points where large tracts of land get locked into desertified states, as one example.

So there are examples of how we can induce tipping points when pushing land and water systems too far. Now nothing is static, and if you load climate change on top of this we see projections into the future that would put even more strain on particularly fresh water systems.

Here you see a very recent analysis by Jacob Schewea and colleagues at the Potsdam Institute for Climate Impact Research trying to analyze what would happen with fresh water resources in the world at 2 degrees C warming, so a point at which we most likely will be quite soon already within this century.524

Now if you look carefully at this map you’ll see the red areas in the world where the projections show, when we gather all the knowledge that we have today, regions that will lose 25 or more percent of average annual runoff. And losing so large [a] portion of fresh water resources is truly a risk of crossing tipping points for both ecosystems and food supply will be jeopardized.

So these are examples of moving and the risks we would take if several boundaries move out of their safe operating space, in this case climate, land and fresh water.

So if we move into fresh water and the diagnostic of what makes water a planetary boundary it’s in its fundamental diagnostic the role water plays as the bloodstream of the biosphere. Water regulates everything we know in the biosphere, all vegetation growth, all biodiversity depends on fresh water.

Humans depend on fresh water, and this map shows just the degree of water scarcity in the world as projected until 2025, taking into consideration fresh water considerations in ecosystems and human needs.

So what we’re recognizing increasingly that the global hydrological cycle, which is finite, is fundamentally a prerequisite for the stability of the Earth system: it regulates climate, it regulates biodiversity, and it’s fundamentally important for social and economic development.525

Now what makes water so interesting from a planetary boundary perspective is that it flows yearly in its hydrological cycle, evaporating from land and oceans, creating clouds, falling down as rainfall, infiltrating into the soil into what we call green water, the portion of rainfall that forms soil moisture and then flows back into the atmosphere as evaporation and transpiration, totally constituting vapor flows, and one portion flowing off on land and as groundwater flow, what we call blue water, the liquid water that fills up our lakes, rivers, wetlands, and dams.

Now what we’re learning increasingly is that we have to have sustainable management of landscapes at large scale to safeguard rainfall, what we call precipitation sheds, which is what’s the area that we depend upon as a source of our rainfall?

And this is an illustration not only why water is a planetary boundary, because it’s safeguarding the management of the fresh water cycle, from the local watershed scale to the base of the global scale, regulates the entire flow of fresh water which, again, regulates climate and biomass, but also how intimately coupled fresh water is to land management and deforestation.526

So these are key justifications from science making water and land so important as planetary boundaries. Now the question is how much water do we need to safeguard in order to stay in a Holocene-like state?

In our original analysis we did this from a global perspective, we looked at the global hydrological cycle, we looked at how much water can we take out in the large basins And biomes of the world before we start seeing evidence of tipping points, and calculated a global number of the maximum amount of water that we can consume in our rivers before we end up with a situation where we could see evidence of tipping points. But we did this from a very global analysis, synthesizing literature.527

Now we’re adding a very important piece to the evidence, namely digging ourselves much more down into detail in all the river basins in the world, exploring based on vast amounts of knowledge that is out in the field on how much water do we need to sustain in our rivers to keep ecosystems functioning, what professionals call environmental water flows.

And what you see here in this graph is the latest update of a bottom-up estimate of the global fresh water boundary based on this analysis for every basin in the world, what’s the minimum amount of fresh water we need to sustain in order to keep basins resilient?

And the exciting thing is that we’re now combining these two analyses of a top-down global estimate of the planetary boundary for maximum amount of fresh water use with a bottom-up analysis of how much fresh water must stay in the basins to keep basins, large landscapes operational. And this leads to our estimate of the final planetary boundary.

But before coming to the numbers around where the boundaries land, let me just close with a kind of summary statement with regards to the importance of land and water for the human future on Earth.

We are soon nine billion people on our planet. Everyone with a right to development and the basis for development will be access to food and fresh water. Recent estimates shows [show] that just to feed humanity in a world in 2050 with nine billion people will require potentially an increase of fresh water use from our current 7000 cubic kilometers of fresh water per year, both in irrigation and rain for that culture, to in the order of 9000-10 000 cubic kilometers per year.

This in a planet where already 25% of our large rivers no longer reach the ocean because we’re taking out so much water to produce food. Now the question is can we transition the world on fresh water land within a safe operating space?

And John Foley and colleagues here at the Resilience Centre recently did a very significant synthesis asking this question: can we feed the world within a safe operating space?

And the answer is that yes, in fact we have so many innovations and so much untapped potential to improve the efficiency and productivity of fresh water use that we can in fact attempt to achieve this grand challenge of feeding humanity within a safe operating space. Yes, we are in a very challenging position in terms of sustaining fresh water and land within a safe space. On the other hand we can, within a safe space, also meet demands for a growing population.

In terms of definitions of the boundaries then what we’re done is that the original estimate was to say: what’s the maximum amount of cropland that we can expropriate beyond which we risk tipping risks induced by land use change?

That estimate was set at a maximum cropland extent of 15%, and we have today transformed 12% of the world’s land surface into cropland. It’s 12% for cropland, but it’s forty percent if we include also grazing lands. But we took cropland because that’s a set of data that we have quite a good handle on. In the updates that we’re doing we are, as I mentioned, reversing this to rather say how much forest do we need to maintain in order to sustain Earth resilience? And our estimates show that we need to keep in the order of 75% on average for all the big forest systems, and we are today actually at a situation where we have cut down more Than 25%, we actually only have 62% of forests left on Earth. So we’re already in a danger zone with regard to the planetary boundary on forests.

But importantly we’re actually able today to make the first estimates for how much rainforest we need to keep, and our estimate shows we need to keep 85% of rainforest systems, that we need to keep 50% percent of our temperate forests which play a lesser important role in terms of its total coverage to maintain Earth resilience, and that we need to keep in the order of 85% of our boreal forests to stay within a safe operating space.

And this is a signal or a way of showing that the planetary boundary at the global scale can actually be translated to the operational scale of forest management in large parts of the world. But it does, and I really want to remind ourselves of this, forests do not respect national borders. It shows that it’s a global concern to safeguard the remaining forests on Earth.

Similarly for fresh water we maintain. The original analysis that we need to keep consumptive fresh water at the global scale 4000 cubic kilometers of fresh water per year. That is the boundary that we feel we still have evidence to support. But then we’ve done this bottom-up analysis of the amount of environmental water flow in all the basins in the world, which ends up with an aggregate boundary corresponding to in the order of the same magnitude as our estimates top-down, but it gives us percentages of maximum allowable withdrawable fresh water at each river basin in the world, which ends up in the order of 25 to 50% of fresh water must be kept in the rivers, and that there’s a large variation here is that it depends for each basin on how much fresh water there is, if these are permanent basins, if these are intermediate basins, if these are only infermeral basins, the flux intensity, etc. So there’s a lot of intricacy here but it just shows that we can operationalize this at the level of management.

So overall land and water as fundamental boundaries regulating Earth resilience and our desired Holocene state. They operate at the local level but aggregate into impacts at the global scale, interact very closely with particularly biodiversity and the climate system, and are fundamentally part of the operational management for a sustained prosperous future on planet Earth.

Antropoceno XXIV – A Fronteira da Perda da Biodiversidade

Biodiversity loss

It may surprise you that biodiversity is one of the planetary boundaries. But when one sits down and reflects a bit it becomes very obvious that biodiversity must be one of our planetary boundaries.

Think of it, without the living species everything from vegetation, trees to animals and small insects, pollinators, we would have no biomass, there would be no carbon sequestration, there would be no rainfall because a large portion of our fluxes of water originate from the canopy, from vegetation transpiring and evaporating water back to the atmosphere. It regulates the flows of fresh water, regulates the flows of carbon, nitrogen and phosphorus.511

The living biosphere is a fundamental component in regulating the stability of the entire Earth system. And this relates to two components. One is the genetic diversity; the treasure of genetic code, which forms the adaptive capacity of the entire Earth system. But it’s also the diversity of functions that we know today that in order to develop, for example, food for a world population of 7 billion people we need the functions and landscapes for pollination, the function of microorganisms in the soil to develop organic matter which in turn delivers nutrients for plants, without which we would have no food.

So we need to explore the functional diversity and the genetic diversity in the rich treasure of living species on Earth. And this forms part of a core fundamental part of a living planet. The drama is that we’re really mismanaging biodiversity in the world. In fact we are today, based on the observations we have, in the sixth mass extinction of species in the world, the first extinction to be caused by another species, and one of these six, for example, being when we lost the dinosaurs 65 million years back on Earth.512

So these are big, dramatic changes, illustrated here for example when it comes to how we’re dealing with global fisheries. Just over the past sixty years from the 1950s and the onset of the great acceleration when we started the exponential rise in pressures on planet Earth, you see here the extraordinary social-ecological journey of not only increased landings of fish, but also that fish efforts are changing dramatically from small scale fisheries to large scale industrial fisheries where we are basically vacuum cleaning large tracts of oceans, not only in shallow waters but also in deep ocean regions.

We have the classic examples of collapse of fisheries; like the cod fisheries off the shores of Newfoundland, where we’re learning unfortunately that once we cross a tipping point with regards to loss of fisheries we can actually lock the system in a situation where the fish does not even come back.513

So these are big, dramatic changes that we need to incorporate in our understanding of the resilience of the Earth system. We also have interactions between species.

This is an example of how delicate the system works in terms of relationships between seabirds and fisheries. A large synthesis across essentially all marine systems across the world shows that when we overfish and lose more than 30% of fish stocks that has an abrupt impact on seabird populations which go through, and cross a threshold leading to abrupt changes in populations. So loss of one species in this case over-fishing, has a propelling effect on seabird populations which risk collapse, in fact, in many parts of the world.514

So again the risk of not connecting diversity in species and thereby not understanding that this can lead to propelling effects across the world. A fundamental, very essential part of our own future is of course the ability to produce food. And there’s another example of how a function in ecosystems simply provides us with a free service, namely pollinating insects.

And here’s one example of a global concern among farmers, scientists, citizens in general, that we’re losing pollinating bees at a very rapid pace, to the extent in fact that some agricultural regions are collapsing. We have human beings have to step in and function as human insects to pollinate apple orchards in China. We have examples of collapse of pollination in some parts of the UK, United Kingdom, because of overuse of pesticides which led scientists to pop over to neighboring countries in Scandinavia and try to borrow bumble bees to be used as pollinators in their own agricultural systems.515

So again, understanding that biodiversity – without biodiversity we cannot have modern agricultural systems, and therefore we get locked in an undesired state in terms of delivering human well-being.

So in summary, what occurs is the recognition that biodiversity is fundamental for the regulation of the Earth system, it’s fundamental for human well-being. We tried based on this evidence to identify what could be a good control variable, an indicator for a planetary boundary on biodiversity?

We took as a first starting point an indicator that maps out the rate of extinction, how many species we’re losing, over time. And this indicator called the extinction rate per million species per year, which is a good indicator of the pace of loss of biodiversity.

The natural background rate of loss is roughly one species per million species per year, that’s the normal background rate. We estimate as a first guess that a boundary lies somewhere between ten and hundred lost species per million species each year. So the boundary was placed at ten species lost per million species per year. Now today we’re losing species at roughly ten to hundred times faster that rate. That’s why we can today say with quite a high degree of confidence that we’ve actually transgressed and are in a danger zone on biodiversity.

But we’re also exploring to understand an even better indicator for biodiversity because extinction rate only gives us a measure of diversity, it doesn’t give us any measure of the functions biodiversity plays.

And here I’ve just given one example of how the science it is advancing in terms of mapping out the functions that biodiversity plays for humanity.

This is illustrated from another index that is called the mean species abundance, which is an average measure of not only the number of species in each ecosystem in the world, but also how many in each species group we have grouped in terms of functions.

And here you have a map of the world of the situation, the state for biodiversity in terms of species abundance in the year 2000. And you can see in red the hotspot regions where we are truly in a very risky zone in terms of losing too much of species abundance. But in green you have regions that are still in a safe operating space.

And here you have the projections into the future, up until 2050, of the risks if we do not transgress ourselves, or if we do not move ourselves, into a safe operating space in terms of safeguarding biodiversity.

We’re right now working very actively in improving this analysis even further to say that extinction rate is a good measure of the diversity and richness of species in the world, but we’d like to have a better measure to measure and to determine the functions that biodiversity plays for human well being.

And one of these indices is a very exciting new advancement on something called the biodiversity intactness index, which is an even better measure on functional groups for the role played by ecosystems for human well-being.

And this is something that will be hopefully developed further and much more broadly in the world because so far it’s used in just a few ecosystems in the world.

But overall, in summary, biodiversity as a key for human well-being, biodiversity as a key for regulating the stability in the Earth system.

Science shows clearly that biodiversity is key to regulate a world that remains in our desired Holocene-like state, and science can now put the first quantitative estimates of a safe boundary within which we have a high likelihood of being able to rely on biodiversity, the richness of all species on Earth, as a support for human development.

Antropoceno XXII – A Fronteira do Ozono

All life on Earth depends on the extraordinarily thin layer of livable atmosphere which envelopes the biosphere in our Earth system. But above the atmosphere in the high atmosphere, roughly ten to fifty kilometers above ground, we have the stratospheric ozone layer.464

And the stratospheric ozone layer is a protective shield that enables life on Earth by reflecting back harmful ultraviolet radiation from the Sun. So clearly the ozone layer is a planetary boundary enabling human prosperity and development on Earth.

The stratospheric ozone layer has for a long time been understood as being absolutely essential for living conditions on Earth. And in the early ’80s scientists started to observe something absolutely extraordinary namely a rapid, abrupt drop in the thickness of the ozone layer.461

This was a huge surprise, in fact scientists even thought it was an error in the scientific observations. But through fantastic research by top scientists in the interface between atmospheric research and chemistry soon it was proven that the reason for this depletion was that certain chemicals that we used as refrigerants, as solvents, propellants, the whole family of chlorofluorocarbons were moving up the atmosphere through high winds and reacting with ozone and – and breaking these molecules apart and thereby depleting the stratospheric ozone layer, threatening life on Earth, and particularly health for humans, by risks of rising skin cancer, cataracts and damage also on vegetation, food production systems on Earth.463

This led in the mid-1980s to the extraordinary step where the world gathered around a protocol, the famous Montreal Protocol, to ban chlorofluorocarbons from use in refrigerators. And this in turn has led to a success story where a boundary of ozone depletion was transgressed in the early ’90s and now we’re actually moving into a safe operating space, showing that humanity in fact can collectively as all nations on Earth work together to operate within a safe operating space.463

So we are moving in the right direction on ozone, but what is very important to recognize is that we’re still observing an ozone hole, particularly over the polar regions, and the classic ozone hole is in Antarctica, which is due to the combination of ozone depleting substances, continued emissions of chemicals, but also the fact that the sins of the 1980s are still haunting us because of the delay time in much of these chemical reactions, which is also a reminder that, uh, we need to apply the core thinking of planetary boundary theory which is a precautionary principle, because what we do today, which we sometimes do not even understand, can have a harmful effect on the Earth system, can actually come back and hit us many, many decades later.

I’ll give you a small example that comes from the Nobel Laureate Paul Crutzen, who was one of the three scientists observing the depletion of the ozone layer in the early 1980s. The industry at the time had a choice of two molecules to develop the refrigerating chemicals that were used worldwide, either chlorine or bromine. And just so happened by pure coincidence that the industry chose chlorine. That was very lucky for humanity because it just so happens that chlorine has several magnitudes lower harmful effect on ozone. If the industry in the early ’80s instead has chosen, or rather in the early ’60s all the way up to the ’80s when we banned the chemicals, had chosen bromine as the carrier of refrigerating systems across the world we most likely would have had a catastrophic tipping point that would have undermined human development on Earth.464

So that’s an example of how close we were of what we can call a planetary scale disaster, and why thinking in terms of defining planetary boundaries is so essential. Science has come to a point where we are at a position where we can define a control variable, which we have chosen as the thickness of the column of ozone across the planet.

And this gives us a very good, robust, science-based definition of how much we must maintain in terms of ozone, and thereby also translating that to avoiding chemicals that can destroy the ozone layer.

Is the problem finally resolved? Well the answer is unfortunately no. The most damaging chemicals used in the early ’80s are not on the market any longer, but we’re using other types of refrigerants, and methane is a compound that also poses a threat to the stratospheric ozone layer, and we see other emerging novel entities that could actually threaten the ozone layer, reminding us that planetary boundary processes do interact, and one very strategic way of protecting the ozone layer is also to have a strong boundary on chemical pollution.

Antropoceno XXI – A Fronteira da Acidificação dos Oceanos

We’ll be talking about ocean acidification. What I’d like to do is touch on three things, first the chemistry of ocean acidification, the consequences of ocean acidification, and some of the connections, not just in the planetary boundaries framework but outside that as well.

So let’s start off with chemistry. The first slide here shows the carbon dioxide budget globally, and it comes from the Global Carbon Project based in Australia.451

And towards the left you can see the amount of carbon dioxide emitted by human activities like fossil fuel burning or cement production. That’s the arrow, the big arrow, going upwards. There’s another upward going arrow and that comes from the carbon dioxide emitted from land use change.

Of all of the carbon dioxide we emit to the atmosphere about half of it stays there, and that’s why carbon dioxide concentrations are increasing. But what happens to the other half? Well, about 25% or so goes into terrestrial ecosystems, that’s the downward going arrow to the trees, and the other 25% ends up going into the oceans.452

So what happens when you dissolve carbon dioxide in the oceans? Well the carbon dioxide forms a compound with water called carbonic acid, which then dissociates – that means it splits up and forms two ions – a proton H+ and a bicarbonate ion HCO3-. That can dissociate again, giving off another proton and a carbonate ion. And each time a proton is added to water it becomes a little bit more acidic. So, is that a global issue? Well, yes it is.

This particular image shows three different plots of ocean pH as a function of time.

The one on the far left is a pre-industrial case. And the color coding is proportional to the ocean pH, so you can see that the red colors are about 8.2, green colors are 8, the purplish-blue colors are 7.8-7.9.453

And you can see in the pre-industrial case most of the oceans were 8 or above in terms of pH. Present day it’s still around 8, but there are fewer areas which are above that. Predicted for the end of the century you can’t see any places at all with pH of 8.

Now that doesn’t sound like much, right? But keep in mind that a tenth, the 0.1 pH unit, is about a 26% increase in acidity of the oceans. So we’re talking about a lot. What are some of the consequences, uh, of ocean acidification?454

Well this plot shows a lot of different kinds of marine organisms, and it’s not so important, you can take a pause and look at more detail, but what you want to – to concentrate on first is increasing ocean acidity is going to the left in these plots, and calcification rate, that’s how rapidly organ– organisms in the ocean turn carbonate into a – into a shell is on the vertical axis going up.

And most of these plots either have a little bit of a – an inverse U-shape or it’s just going down, which means that most organisms in the oceans don’t like it when it becomes more acidic, they slow down the rate at which they make a hard shell out of the carbonate in the oceans. What does that mean really?

Well if you’re a coral reef you’re under stress from ocean acidification and other things like ocean warming and different kinds of pollutants. And you can go from the kind of beautiful, vibrant, very bio-diverse reef you see on the right to the kind of bleached reef you see on the  left as a result of those changes in the ocean, including ocean acidification.455

What are the implications and how rapidly can this happen? Well the graph on the top shows predicted increases, in carbon dioxide concentration for the atmosphere under a number of different scenarios into the future.

The bottom shows the aragonite saturation, that’s the point at which the equilibrium shifts from making aragonite, a kind of calcium carbonate, a soluble or an insoluble compound in the ocean, and that you can see will happen by the early mid-century for the southern ocean under most all of these scenarios into the future. So the point at which aragonite becomes soluble, or coral reefs might have a very, very difficult time, uh, existing at all, will be about mid-century or so, not too long from now.456

Now that’s not the only stressor that marine organisms are facing. It’s one of the more important ones, but if you look at some of the other ones, like ocean warming, and other kinds of pollution you can see that the oceans are facing multiple stressors.

And in particular, on this plot, if you looked at the hatched areas, much of the southern ocean and much of the north Pacific and Atlantic oceans, will be faced by a number of stressors including, uh, ocean acidification. And all of the organisms that live there will be in a much more stressed environment.458

You can get more detail about this, and other issues as well, in a book, Managing Ocean Environments in a Changing Climate. It tries to put all of these different stressors together and tells you how they fit with each other.

Which moves us into the connections part of the presentation. So you’ve seen this picture before, or at least some version of the picture.

This is the image of planetary boundaries. It’s not by chance, that ocean acidification and climate boundaries are right next to each other, because the driver for both is the same, how much carbon dioxide we emit to the atmosphere.

So this next to the last slide shows some of the connections between planetary boundaries, ocean acidification and the couple of other things, like food production. So you can see on the top we can produce food from terrestrial sources or on the bottom we can produce food from marine sources.

And the things that connect them are our planetary boundaries. So you see chemical pollution, for instance, from production of food on land might negatively influence coastal areas where we farm or fish, uh, for food. And nitrogen and phosphorus cycling, and what we’ve been talking about so far in terms of ocean acidification, the amount of carbon dioxide that we emit into the atmosphere.

And the important thing with this slide is to realize that all of these processes are fundamentally connected with each other.

You can’t really pull one apart and look it all by itself. Having said that though we’ll like to do a little bit of a reminder of what the ocean acidification boundary actually is.459

It’s written in terms of aragonite saturation, that is, it’s a chemical equilibrium, and this might be a poster child for planetary boundaries in the fact that that’s a very, very easy boundary to define, because it is a chemical equilibrium.

If you add a little bit more carbon dioxide to the oceans aragonite becomes saturated, or unsaturated, so this is probably the easiest to define of all the planetary boundaries, and you can see on this slide exactly what it is.

Antropoceno XX – a Fronteira das Alterações Climáticas

In this lecture we provide scientific evidence why climate change is a planetary boundary, and the basis for defining the boundary for climate change.

It originates, not surprisingly, from the fantastic scientific explorations of our recent paleoclimatic conditions on Earth, again the stable climatic state we’ve had in the Holocene, shown here over the past 2000 years of reconstruction of temperature which varies at a maximum of +/- 1 degree or 2 degrees Celsius.


And as you see at the end the extraordinarily rapid pace of temperature rise in the world over just the past 150 years, since the Industrial Revolution, and our initial large scale emission of greenhouse gases from our industrial development.

This is the basis for the fundamental evidence that builds up the arguments around climate change. It becomes even more dramatic if you connect the past with the future, which is shown in the next graph showing the IPCC projections up until the end of this century.

And it’s absolutely extraordinary to see the Holocene stability which is again this churning up and down with a +/- 1 degree Celsius, and the fact that we are today heading on average along a pathway that will take us to in the order of 4 degrees Celsius warming during this century. And I think it’s absolutely clear just from this graph that we are at risk of pushing ourselves very rapidly outside of the Holocene stability.442

Now up until today we have already increased global average temperature levels within the order of 0.8-0.9 degrees Celsius over the past 100 years.

What you see here is the distribution of that heat across the planet based on modeling and observations, and what you see is that in fact many regions in the northern hemisphere have actually even more warming already today, which is for example affecting one of the regulating systems, namely the polar regions in terms of its feedbacks in the stability of the Earth system.

The next insight building up the evidence for a climate boundary is that sea level rise is occurring at the pace of the projections we have or even faster. In fact much of the evidence today points at the risk of us underestimating the pace of sea level rise, particularly because we’ve underestimated the rate of melting which potentially could be irreversible in parts of Antarctica.443

We’re also seeing unfortunately increasing robust analysis looking into the future that we’re following what I would actually call a disastrous pathway that leads us on average to three, four, potentially even higher, warming in this century. And that is coming out of the Intergovernmental Panel on Climate Change (IPCC) last, the most recent 5th assessment.

And here you see the synthesis graph showing the different scenarios to the future. The red line is the pathway that takes the world towards a totally undesired not Holocene-like state of 4 degrees C warming, and we know unfortunately that we’re following this path. So this is again increasingly showing that we need to do something very rapidly in putting a boundary on climate change to avoid moving outside of a desired state.445

The next piece of analysis is related to the risk of tipping points and risk. And here science is advancing in a very profound way. We’re understanding the climate system much, much more in detail, and particularly how the climate system interacts with the other planetary boundary processes such as land, water, oceans, and biodiversity.

And this graph may seem a little bit complex, but it’s a really important insight that is coming out of the three last IPCC assessments. So what you see here is a risk assessment shown in red ambers, which has become a seminal and very famous set of graphs, of the risk analysis of the 3rd assessment to the left, the 4th assessment in the middle, and the most recent 5th assessment to the right. And what I want you to look particularly to is the column furthest to the right in each assessment which has a small darkened little block attached to it, which is the assessed risk from science of large scale discontinuities.446

To put it in simple language, the risk of human-induced catastrophic tipping points. So this is the risk of us destabilizing the entire monsoon system, or irreversibly melting the Greenland ice sheet. And if you look carefully in the third assessment the risk of such large-scale discontinuities was assessed to occur at a point where the warming reached in the order of 4 degrees C. So on the Y-axis you have average temperature at which we risk these kind of catastrophic tipping points. But as knowledge advances, as our understanding of [how] the complex Earth has evolved, just a few years later in 2007 with the fourth assessment, as you’d see if you look carefully the threshold at which catastrophic tipping points can occur is down in the range of 2-3 degrees C.447

And now in the most recent 2013 fifth assessment you see that the assessment from science is that these kind of large-scale discontinuities could actually occur even lower – in the order of 2 degrees C warming. And the reason why this is occurring is that we’re understanding more and more about resilience, about the risks that we have surprise and thresholds in the Earth system. And this to me is the most fundamental piece of evidence showing that a planetary boundary approach on climate is absolutely necessary because for one, at already very low temperature rises we today have evidence enough to say that the likelihood of large scale catastrophic changes is highly probable. And secondly, it’s highly uncertain. It’s so complex that we need to apply a precautionary principle where a boundary position is a position of safety beyond which we enter this area of uncertainty. And just to really hammer that point home, when you translate the latest assessment of the IPCC, our 5th assessment in terms of risk, something absolutely astonishing falls out.

We are today, in 2014, at a concentration of greenhouse gases for all gases, so carbon dioxide plus the other gases including methane, nitrous oxide, chlorofluorocarbons, and the short-lived climate forcers, including soot and sulfates and organic carbon, we are at 450 ppm.

Now we have taken the data in the IPCC and just translated them in probability of reaching different degrees at 450 ppm, and that is shown in this graph.

So on the X-axis you have temperatures and on the Y-axis you have the probability of reaching that degree of temperature at 450 ppm, at our current concentration of greenhouse gases. And look at the point which I’ve put on this graph which is 6 degrees C. I’ve taken an extreme warming, 6 degrees C is something totally outside of anything we can imagine, it’s an uninhabitable planet, it’s a degree of warming which any person, even a climate skeptic, would agree is totally unacceptable for humanity.

What’s the probability at 450 ppm according to the latest IPCC that we reach 6 degrees C Well on the Y-axis you see that the probability is a staggering 1.6%. Now what does a percentage, a probability of 1.6% mean? Well to give you and equivalent it would be the same as accepting that we have 1,500 aircrafts crashing every day. So it’s a probability level for catastrophic events, which in in any other sector of society would never, ever accept.

In fact, some of  the large reinsurance companies after the IPCC released its report, clearly pointed out that we’re reaching a point of risk which goes beyond the point where they potentially can no longer issue, insurances because they can not be liable for the large scale costs that would be incurred if these kind of catastrophic events would be allowed to happen. So we’re entering truly a danger zone with regards to climate.

This is shown clearly in the next slide here on our analysis of how much forcing we are loading on the climate system. So what you see here is the last half million years how we are able to reconstruct in a very, very adequate way how much greenhouse gases we have in the atmosphere, how much forcing that includes. Forcing is the amount of watts, the energy that is trapped per square meter because of the greenhouse gases in the atmosphere. And look at the future.

What you see here is how we are rapidly moving out of the Holocene, moving out into a forcing and temperature rise which is way, way outside of the Holocene equilibrium. Now when we all take all this science together and synthesize it to define the boundary, we then apply our theory of a safe operating space, an uncertainty zone, and a danger zone, and we find that the science indicates that at the range of between 350 ppm and 450 ppm the science is well in agreement that here we have a risk of crossing catastrophic thresholds. And therefore we apply the boundary at the safe lower end of that uncertainty which is 350 ppm for carbon dioxide. And there you have it, that’s the way we place the boundary for climate change.