Graeme Pearman has been Chief of CSIRO Atmospheric Research since 1994. He was elected to Fellowship of the Australian Academy of Science in 1988 and has been a member and chair of many Australian and international meteorological/global change committees. He is also a board member of Greenfleet Australia. He was a recipient of a United Nation’s Environment Program Global 500 Award in 1989 for his active involvement in a national awareness program on climate change and in 1999 he was awarded the Australian Medal of the Order of Australia for his services to atmospheric science and promotion of the science of climate change to the public.

Sustainability: Where are we now?
by Dr Graeme Pearman

Introduction
A planet under stress (the bad news)
Human responses (the good news)
Transition to sustainability – a vision
Conclusions
Questions/discussion

Introduction

It is my task to try to set the scene for the papers that follow. I will do this by considering three topics:

• A planet under stress: a brief audit of environmental deterioration, indicating that our current practices are not sustainable;

• Human responses: some of the first very positive actions that are being taken to redress some of these issues, and

• Transition to sustainability: my idea of the concept of sustainability, and how we as scientists might contribute to the challenge of making a transition to a more sustainable future.

Many of you have seen images such as the one shown in Figure 1, when, with modern technology, we can stand back sufficiently far and look at the planet as a whole. It is a night-time picture of the planet. It indicates where energy is used and where human populations are. It shows a population distribution that is weighted by GDP or capacity to use energy and derive amenity from it. It shows the hot points, if you like, of these weighted effects, and that Australia by and large is a small contributor to this outgoing radiation from the planet.

Figure 1

The population/health issue
Population is a key underlying issue, and associated with it are issues of health. You would all have seen pictures of the population growth of the planet, and the virtually exponential growth over the last century or so. Between now and 2025 we are anticipating a 33 per cent increase in population – another 2 billion people (Figure 2). Bear in mind that about 2 billion of the world's present population do not contribute to the lights that we saw in Figure 1 – but they certainly wish to participate in the wealth associated with the use of energy.

Figure 2

An important aspect of this population growth is that, at least in the developing countries, the rate of growth is slowing dramatically, and so the concept of there being a stabilisation of global population in this coming century is a real possibility. Figure 3 shows what could happen in Australia, with hypothesised levels of fertility and immigration. There is a real possibility that in Australia, by the middle of this century, we could see population stabilise or even decrease, depending on what we do with regard to immigration policy. The latter is obviously a key issue and one that is on the public and political agenda, but it is yet to be debated openly and in detail and in the context of the challenges of a transition to sustainability.

Figure 3

Food
Associated with population growth are the demands – the food demands in particular – for now and into the future. Take global fisheries as an example. The global catch has increased by about 100 per cent every decade over the last four decades and this has led, for almost all fisheries in the world, to overfishing and resource depletion. About 70 per cent of the commercial stocks are now fished to a point where the contribution that those species make to the balance of those particular ecosystems is impaired. In Australia we have by and large, through the application of good science and good management, pretty good stock evaluations and protection of our species. But in fact we don’t have control over many of them, and foreign fishers are actually impacting on the sustainability of a number of our fisheries.

Then there is agriculture. There are many aspects of agriculture that we could refer to but I will pick up here on the theme of the impact of agriculture in the removal of natural vegetation, and how that has impacted on the penetration of more water past the root zone into the underground water, which then leads to the migration of water and salt to the surface. At the moment, it is perceived that in Australia there will be something like three times more salinised land by the middle of this century – that equates to a rate of growth of about a football field every three minutes.

Then we need water to actually produce the food. It is often not realised that each of us, effectively, consumes a million litres of water a year in order to sustain our lifestyles. Figure 4 gives an explanation of why that number is so large. This is what we demand in order to maintain our lifestyles, for our own food and for the food that we sell for our prosperity.

Figure 4

Resources
Then there are the resources themselves. Of course, water is important for reasons other than food generation, as are soils and biomass. Salinity is a big issue (Figure 5), and in economic terms it is estimated to be costing us around $100 million to $200 million per annum in lost agricultural productivity, now – not in the future. It is already estimated to be impacting on a huge number of species – will they be able to survive and avoid extinction? By 2050, 17 million hectares of Australian land is expected to be at risk through dryland salinity.

Figure 5

Biodiversity
Biodiversity itself, the preservation of ecosystem functions, is a reminder that natural ecosystems have more than aesthetic, cultural and spiritual values for us. They are also sources of food, timber, pharmaceuticals and so on. They play a role in the purification of water and the maintenance of air quality, and they are an intimate part of the climate system of the world, both in the way they impact on the radiative budget of the Earth and in the way they actually interface with the hydrologic cycle. In all of these ways, the ecosystems that we are disturbing are at interplay with the wider issue of sustainability.

Energy
And what about energy – the energy that drives those light bulbs that dissipate this energy to space as we saw in Figure 1? If we look at Australia's oil and condensate production in Figure 6, we can see that the history is pretty clear. The massive growth in the use of fossil fuel that has been available through the use of oil was obtained in this country through a limited number of large reserves, and you can already see by now that in fact we cannot do that any longer. There are no longer large enough reserves, and we are actually getting our oil from a lot of small reserves. This is a picture that is repeated around the world:

Figure 6

But the disturbing thing that Figure 6 shows for Australia is that before the end of this decade there is a massive decline in the availability of oil reserves in this country. That means that the proportion of imported oil that we will require over this next decade will rise from somewhere around 10 or 20 per cent to 60 per cent. And for every 1 per cent increase it is estimated that the costs for the country are $100 million in balance of payment terms (Figure 7). So this is an important and very controversial issue.

Figure 7

Some people are polarised about whether this is going to happen, and indeed I remember giving a paper nearly 30 years ago – chairman Ralph Slayter probably doesn’t remember this – but at a conference that he organised, I showed a lot of scepticism about whether the predicted shortfall of oil would really occur. It didn’t occur at the rate anticipated at that time, but I think the evidence now is that oil is not going to be able to meet our energy demands. Even if we were to discover some new large resources over the next 10 years, we still, I think, would see a decline in the availability of oil. Peak production of oil is at a turning point, and it is a turning point for the global population. What do we do without it? Which way do we go?

A hundred years of growth of energy use through coal and oil development is at an end, and we are about to see that turn around. There is a transition to a decline in oil, and this is going to bring about all sorts of tensions. If we go to an oil company and ask them what their scenario for the future is, Figure 8 illustrates what they say. This shows exactly what I have been saying: fossil fuel contributions to the total energy demand, and particularly to the growth of future energy use, is going to tail off. By the end of this scenario we have a picture of a complex of all sorts of different sources of energy, many of them renewable, that will be contributing by the middle of this century. This scenario only goes to the middle of this century!

Figure 8

Climate and air quality
Then there are the issues of air quality, from the point of view of air pollution in the cities and the urban regions, and also the climate issue, the air that we breathe. I will come back later and say that this is actually a fairly positive story, but there are issues that we are not so positive about. For example, it is only very recently that it has been realised that a significant amount of mortality in cities relates to very fine particles – not to the particles we can see, but to the finer particles – and the relationship between the physical scientists and the medical scientists on this is growing very rapidly. In the Australian public’s view, air quality is the most serious environmental issue. And in fact it may turn out to be that they are quite justified in feeling this way.

But in the climate issue we are changing the global composition of the planet. Figure 9 shows what has happened to carbon dioxide in the atmosphere in the last 1000 years. We are now above 350 parts per million (ppm), whereas for most of the last 1000 years we were bobbing along at about 280 ppm. Indeed, from similar studies we know that for the last half a million years we have never had concentrations in the atmosphere anywhere near the ones we have now. From geological evidence it is probably 20 million years since the atmosphere had as much carbon dioxide in it as it has at the moment.

Figure 9

This is causing the temperature of the planet to change. I will give you one example – Figure 10 – which shows the minimum night-time temperatures in Australia, which are a bit more sensitive to general warming than the average. You can see that it is not just patchy; it is happening everywhere but more in some places. And indeed the impacts of these changes are now being seen in terms of overnight frost frequency and the impacts on vegetation.

Figure 10

To look at rainfall, we have a very serious problem in the southwest of Western Australia, where the precipitation rates have not exceeded the long-term average for 25 years (Figure 11). We don’t know whether this is climate change, although climate change predictions would suggest that this is the likely trend across all of the southern part of Australia. Whether it is or not doesn’t matter – these people are under stress because they don’t have enough water. We are worried about it in Melbourne, with dams 50 per cent full – but they have only about 20 per cent.

Figure 11

Human responses (the good news)

So what are the good news stories? Intervention, where it has started to occur, has made a real difference.

Species protection
Where people have intervened, for example, in the fishing of whales, we see this marvellous return of whale populations, so that 'whale tourism' is now a big business in many parts of Australia. Anyone who has done it would know how enjoyable it is. And native species, where there has been control over foxes, rabbits and cats, return in a very encouraging way. We cannot replace the species that are extinct, but there is an indication we can do a lot in returning ecosystems to the balance that they had before.

Air quality improvements
In air quality, as I mentioned, there are some negative issues. But the fact is that lead, for example, has gone down in all of the cities of Australia, and in all cities it is now under the national pollution standards (Figure 12). This is because of a number of factors, but mainly because of the removal of lead from petrol. We are intervening and we are having an impact.

Figure 12

Ozone depletion
Then there is ozone depletion, which is a global issue rather than a local air pollution issue. In the 1970s the two chemists who proposed that chlorofluorocarbon gases – which are entirely man‑made gases but long-lived – may interfere with the ozone situation, won Nobel Prizes for that work. And before the work was concluded, before we were really sure that they were right, there was actually a lot of work going on to set up an international framework to phase out the use of the so‑called CFCs.

Let me just show you what the ozone hole is, because some of you may have some confusion. Figure 13 shows the total column amount through the atmosphere as measured from a satellite in 1979. The redder areas, yellow areas, are the high levels of ozone, and the blue, the low level. And also what it was like in 1992. If you look carefully, you will find that ozone depleted somewhat everywhere, as the two chemists predicted. But they didn’t predict what would happen over Antarctica – this massive reduction, particularly in springtime, October, over the Antarctic continent. And the reason for that was simple. They had the gaseous chemistry right, but they did not have the heterogeneous chemistry right. We understand that now.

Figure 13

The good news is that the concentrations of CFCs such as CFC‑11, when we started these measurements at Cape Grim, in Tasmania in the 1970s, were growing in the atmosphere globally at 15 per cent per year (Figure 14). You can see from this that now, because of the international agreement, the growth has stopped. We have control over the release of these gases, and industry has moved on to gases that have a hydrogen atom in them; they are more reactive and they do not have the same impact.

Figure 14

There are a number of messages here, though. International conventions can in fact have an impact, but there is another message here and this is that in order to stabilise the growth of a long-lived gas like CFC‑11 – which has a lifetime of around about 100 years in the atmosphere, similar to carbon dioxide – you have to have massive reductions in the emissions in order to stabilise the concentrations. And that is the challenge for carbon dioxide. It is not simply about maintaining our emissions; it is about reducing emissions massively over the decades ahead of us.

Climate change
International convention
The good news is that there is an International Framework Convention on Climate Change in place to tackle the climate change issue and it has been signed by nearly 200 countries around the world. A protocol still needs be developed, as there was for the ozone-depleting substances, and that is difficult. The convention is about preventing dangerous change to the climate of the world, and as scientists we do not know what that means. We have yet to define what is dangerous – how much change in the climate can we actually have, if we can actually have the control we believe we should have over the emission of these gases? It is a challenge for scientists around the world.

The Kyoto Protocol is difficult. You would all know, through the press, about the US position and the Australian position vis-à-vis that of the Europeans, and the fact that for example Japan is going to join the Europeans, which probably means the protocol will actually come into force by the end of this year or early next year, irrespective of the US.

These are big issues. Why are they big? Because although they are about preventing dangerous change to the climate, they are really about energy. And energy is so fundamental to everything that we do, it is not easy for us to change. We are worried about our trade in coal – of course we are. We are worried about the impacts on a country such as Australia of changes in the way energy is perceived in the marketplace, because carbon will become a commodity if we control the release. It will come to have value it did not have before, and that value will reflect in everything we do in which we have energy. It internalises, in a sense, the environmental costs of changing the climate, in the energy we use, in a way that we have not had before. In the past we have simply released the gas into the atmosphere.

Options exist in agriculture and energy
The impacts of climate change in this sense, therefore, are twofold. There are the direct impacts of climate change, such as the impacts of these higher minimum temperatures that are occurring all around the country right now and the other climate changes that we are anticipating will happen in the coming decades. But then there is the great immediacy of the fact that the energy community, the energy systems of the world, are going to change massively and rapidly, partly – though not only – in response to this issue. The impact of that on communities and societies will be very large.

We have all sorts of other technological options, however, that are positive. Biotechnology to improve food production, double productivity per unit area but decrease the environmental impact to half – Factor 4 opportunities that exist. And sometimes you even have triple bottom line improvements, because there is a possibility for the genetic modification to lead to plant products that have more health benefits than they did previously.

Figure 15

On the energy side, the technological opportunities are just huge, from clean combustion to improved energy efficiencies where payback periods can be as short as 9 months; and yet companies still don’t invest in these. There is a huge number of opportunities. Some of them are on the shelf now and some of them are there for science and technology to develop, in recycling, in renewables, in land-use change – the way we store carbon in the land – and through new automotive technologies.

We have all heard about the hydrogen economy (Figure 16). Well, this is part of the transition to sustainability – the potential for still using fossil fuels but combined with solar-thermal energy to decarbon the fuels and to trap the carbon before it is released, and then to use the hydrogen in the energy system to produce the amenity that we really want from the energy. And to do this in a decentralised way, where photovoltaics and other options for enhancing the available energy at a decentralised location in residential, commercial or other areas gives us a new way of looking at energy. We are in for big change here. The way we generate energy centrally is going to go, and there will be decentralised markets and opportunities. Figure 17 shows an existing solar fossil-power system that uses methane – natural gas – and splits that methane to produce hydrogen, using thermal-solar. This is in action in Sydney at CSIRO. These things can already be done.

Figure 16

Figure 17

CSIRO, together with General Motors-Holden have built a hybrid Commodore (Figure 18). This is one that I am personally interested in, because I was involved in this project. It is a new way of building motorcars. You can buy hybrids now – they are pretty expensive but they are on the market. This Commodore probably can be built with very little penalty in cost, and why? Because it has some very, very good science and technology in it that the other cars do not have.

Figure 18

So what is the opportunity here? These cars actually perform and provide all the amenity of an existing Commodore for half the fuel – 50 per cent reduction. But this improvement is accompanied by the fact that the emission of air pollutants from the tailpipe is reduced by 90 per cent. Wouldn’t it be great if, at the same time, we protected the manufacturing industry in Victoria and South Australia by having them produce cars that the whole world needs (not today’s cars, but the cars of tomorrow), that achieve these goals of greenhouse emission reduction and improved air quality in our cities? That’s the challenge, and they are the sorts of challenges of sustainability.

Figure 19 shows what has actually happened in the transport area. CO₂ emissions have gone down, as engineers have had an influence on efficiency through efforts with compression ratios, direct injection, lightening of the vehicles and so on, and we have had a few per cent improvement each year over the last few decades. But what the hybrid car and then the movement to the fuel cell car allow is a paradigm shift, which gives us the massive changes that we actually really need to achieve the tasks and the challenges of climate change into the future.

Figure 19

If we look at Australia’s business-as-usual energy demands, it might look like the graph in Figure 20, but if we actually introduced the cars, it would slow this down. It is not the solution, it is part of the solution. If we add to that, efficiency in energy use at a reasonable level of investment, then we can do this, and then if we add decentralisation we can see there is a pathway over the next two decades to actually lower the emissions below what they are now, despite our increasing demands. That’s the challenge that we have in front of us.

Figure 20

If you look at the energy cycle, the value chain for energy from mining and exploration right through to end use, then what we can see is that at almost every step there are good ideas, there are good technologies out there that we could harness to improve the efficiency of each step and the ultimate efficiency of the total value chain (Figure 21).

Figure 21

But the important thing is that I am not talking about this as a technological solution alone. That isn’t what sustainability is about, because the other side of the coin is that there are people using these technologies. There are cultural, social and many other human issues that determine whether we do these things, and they need to be evaluated and determined at each of these steps to see whether it is possible to make these changes. Some of the changes are political, because some of the energy systems we have today are determined by political positions that favour one part of the market with respect to the others, and those things need to be fixed. These are social issues that need to be taken into consideration.

Transition to sustainability – a vision

So let me look at the final aspect of my talk: the transition to sustainability, the vision. We have talked about what is happening, both in the positive and in the negative sense, but where do we want to go? What is the vision?

I wanted to speak about this because from my point of view, at least, it is the most important thing that we can address today. The reason for this is that I doubt whether there is anyone in Australia who doesn't actually believe we have to move to a more sustainable future. We are concerned about what this means for our children and our grandchildren, and we want to move in this direction.

But I also, equally, feel from talking to many people about this that there are almost as many views as to what a sustainable future might look like, or how the transition might be made, as there are people. I think that there is a demand – and this is part of the rationale of this symposium – to start airing those views amongst ourselves, to start comparing notes and to start to listen to others when they talk about these issues. It is quite obvious that people who come to this from an economic, social, natural science, or engineering perspective will each have different views, and what we need to do is to have some kind of shared vision as to where we go forward with this particular concept. So I am going to take a risk and give you a feel for my vision – but it isn’t the vision, it is simply one vision.

I think about it from this point of view. There are aspects of our community and our activities that involve our economic wealth and things like the generation of wealth and production and consumption – our economy (Figure 22). There are issues concerning our ecosystems, their sustainability and their health – what we have in the past referred to in a box as the environment. There are the people, the cultures, the health and the security of individuals in our society.

Figure 22

In the past there has been a sense of allowing for the interaction of all these things, albeit in a very low-key, often subliminal, way. And there have been issues of equity that have been put into these things, sometimes in greater strength than others, when people have considered how much emphasis to give to, say, economic issues compared with social issues, or how much respect to give to the environment in a Third World country compared with a developing country and so on. That has always existed. But the exciting thing, I think, is that true triple line accounting is something that is becoming a way of business and a way of actually going about the production of wealth or looking after our societies or environment.

So triple bottom line accounting is a growing area, and it is part of the issue of sustainability. But in the longer term you have to add another component. By and large, triple bottom line is determined on an annual basis, like doing the accounts of a company – Did we do the right thing this year? Whereas sustainability is about doing that on an intergenerational basis as well – Is it the right thing in the long term? And that is the way I perceive sustainability – effectively, triple bottom line accounting with a long-time vision.

Conclusions

In conclusion, population growth and the aspirations of that population growth over the last century have driven local, regional and global environmental change. It is positive. I think we are all seeing that many of these trends are not sustainable. We cannot go on indefinitely changing the climate. We cannot go on indefinitely removing species. But the positive thing is that the impacts have been realised, by and large, and attempts are being made to reverse these trends, and the issue of a concept of sustainability, of a sustainability philosophy and approach, is one that is growing. It promises a number of things. It promises a more equitable balance between the considerations of economic, social and environmental outcomes that span generations. That is the definition that I would put.

But the exciting thing about it is that, despite the way many of us felt about this 10 years ago, it is possible to do this in a way that doesn’t damage our lifestyle aspirations, or wealth and security. There are real opportunities out there for the country, for the individuals that move sooner rather than later, and that’s the real positive thing.

What is the role of science in this? That is the question for this symposium. How do we actually bring together the force, the interests that exist within our science community in Australia, to best serve the nation in this quest for a sustainable future? The twenty-first century, and particularly the first half of the twenty-first century, is going to be about a transition to sustainability – what kind of Australia do we want, and what can we do to contribute to it?

Questions/discussion

Question: You emphasised the triple bottom line aspect, and I see industry is supporting this approach very much more than it was a few years ago. The problem, though, seems to be summed up, in terms of Australia’s energy requirements, in terms of your decrease in oil production and the need to act now in order to address that bottom line of imports that seems to be growing. Government policies seem to be rather to produce more brown coal and try to export that to try to match the bottom line. And the problem seems also to be an inability for Australian industry to act. I think specifically of the case of BP Solar, who have put their large manufacturing capacity into Spain because the demand for solar voltaics is in Europe, not in Australia, and yet they are using technology which has originated at the University of New South Wales. How can we emphasise to government the need to produce policies which are coherent and allow for this triple bottom line accounting?

GP: I can only agree with most of the points you have made. I think the answer is that we don’t have the shared vision. We don’t actually have a national energy policy, and we need one. We need to bring together the expertise that comes from industry, from the science community and from the community at large to formulate the way we think we can go forward and to try to reduce the number of options. Otherwise it becomes somewhat random.

It is true that a lot of the commitment to triple bottom line reporting is coming from the bigger companies. I would have to say, from my limited experience, that it is the companies that are leading the way, not government, in this issue. But I do worry about the many, many small to medium enterprises that in many cases don’t have the feedback that these bigger companies have, and the options. For example, the reason for getting involved in the vehicle that we built was that General Motors and Ford knew about the opportunities in these companies, but people who were manufacturing automatic transmissions didn’t. And these are massive industries for Australia, which need to have a 20‑year vision as to whether in fact automatic transmissions will be something to sell in the future. That was part of the reason for doing it: it was to try to just raise the profile.

Your question is just very complicated. I don’t think I can answer any more, other than to say that this kind of forum and other forums that try to build a consensus across all of the kinds of inputs that we need in order to have this vision is where we need to start right now. And that’s what we really wanted to do through this symposium.

Question: I would like also to ask a question about the interaction between the triple bottom line concept and a company. Those who have been or are company directors know that broadly you have to maximise the benefits for the shareholders – that is, in fact, your legal duty – subject to complying with the laws of the country. Maximising the benefits for the shareholders is principally about maximising one of those bottom lines, putting one of those under the microscope, not three. So it is not just a question of attitude, it seems to me. It is a question of the legal framework in which company executives and directors function. Would you care to comment?

GP: I think you are absolutely right. What I tried to convey was the idea that, in fact, we have always considered a triple bottom line in things that we have done. It is a matter of balance, and part of that balance is determined by what regulations and constraints are placed on the companies. My impression of some of the bigger companies is that they are seeing that, indirectly – not necessarily directly on the bottom line – unless they perform well in a socially accepted way, they in fact in the longer term are jeopardising their own future. Companies like Shell and BP that have very big commitments to changing what they will be in 20 years’ time are doing it partly because they can see the oil crisis that I have mentioned, but also because they can see that these other opportunities exist.

It is interesting, because some of those companies are the very people that will actually argue against regulation to ensure that the other parts of the triple bottom line are met. They will argue for very free markets that allow them to maximise their incomes and their sharemarket prices. So there is a dilemma there: to some extent there will be a need, I think, for some regulation to ensure that this balance is more equitable across the three components, but it would be better if in fact we could choose ways that allow the market to determine. In the case of carbon dioxide and greenhouse, the entry of carbon into the market and the trading of carbon as a commodity would be one way of doing that.

Question: Graeme, you have set the scene of big problems. Bjørn Lomborg’s book The Sceptical Environmentalist would say the world is doing just fine and we don’t have to worry about all of this. Would you care to comment?

GP: I painted a somewhat balanced picture, I think. I think that there is evidence that we are responding, as a global community, to the signs that some of these things are not sustainable and they can’t go on forever. But that particular book – I must admit I haven’t read the whole book, but I have read several chapters including, obviously, the one on climate change – is just a very poor academic work. It is selected information, expressed in a very selective way. I don’t think it contributes to the debate at all.

Question: I noticed on your slide a large section about biomass. A lot of people are very, very concerned about the possibilities of exploiting already chronically dwindling forest reserves. Also, I wonder if you would mention a little bit about carbon credits.

GP: These are huge issues. It is interesting that there is a view in industry at the moment that the position, for example, that the Australian Government is taking with regard to the Kyoto Protocol is actually dangerous. The reason is that it is better for these companies to have some degree of certainty about the future, rather than uncertainty – even if that certainty means that the world will change somewhat. For example, there are huge investments that have been made in forestry on the basis that carbon credits will become a way of trading carbon, and an important way of handling the issues raised in your question: how do you really account for an environmental impact through what is otherwise a profit-making organisation? So carbon credits, I believe, will take place. There are companies that are running internal carbon credit schemes right now and there are some countries that are moving towards trading in carbon, but there is no framework for international trade at this stage. I think it will come. It may come with blocs, such as the European bloc, in the first instance.

What happens if you are out of it? What happens if the rest of the world goes ahead and goes that way? What happens if the World Trade Organisation, as it is showing signs of doing, accepts that environmental performance is a way of actually interfering with, if you like, free trade on an economic basis? There is a chance, a very good chance, that that will happen. Then the picture will be totally different. The United States will be unable to stand aside while the rest of the world is going to jeopardise the way they do things, because they have not agreed to a common climate convention. I think there are issues from the farmers' level as to how we cope with, how we measure, how we determine our actions, whether we are trying to grow crops or whatever, in terms of carbon storage, but it runs right up to these issues as how we are going to trade carbon in the future as a global commodity. I don’t know. I think it is just too early and it is again one of the complexities of the Kyoto Protocol – we are moving fast without having all of those things clearly defined.

Question: Graeme, I don’t know whether you are the right person to address this issue to, but you raised the subject. We would arguably say that oil and gas are the commodities that are closest to extinction – there is a lot of argument about it, but say that’s the case – and they are commodities that are going to disappear. At the same time, we are talking about a transition to a hydrogen economy, where we are going to take these carbon-hydrogen bonds that have had an enormous amount in generating them, break them apart, use the hydrogen for energy and put the carbon dioxide back in the ground. It seems that intergenerational equity would suggest that’s the wrong way to deal with our gas and oil reserves. We should be using the maximum amount of energy out of them, rather than breaking them up just to save the CO₂ side of things. How would you address that?

GP: My first response would be that that’s exactly the kind of thinking we now need. We haven’t been thinking from that point of view, and that’s exactly what we need to do. You are right. The fact is that we may need to do a bit of that over a transition period to actually get through this gap that is going to be created fairly quickly as oil declines. We may have to use gas in what would otherwise be seen as an intergenerational inequity. But it also is only one example that I prepared. There are other ways of actually generating hydrogen more directly through solar and so on that I think will be looked at, and there are options for the future.

The cheapest way, and the quickest way, is to move fairly heavily to using this gas resource. Why is that? I had a very nice slide that I didn't end up using, which shows a distribution of the cost of energy compared with its CO₂ emission. The fact is at one extreme you have coal – very, very cheap, very high CO₂ emission. At the other extreme you have solar photovoltaics – very low in CO₂ emissions but very expensive to generate. And gas is in the middle. It’s actually rather nice, because it is relatively cheap to present, to produce, and it actually emits less carbon.

We are going to have to look at this from a point of view of: what do we actually need to do to survive the next 10 years, but at the same time what do we need to do to move towards this future, this vision, that we have, which is undefined? And we all have different views about it that we will be defining over the next decade.