Earth is presently facing-or will soon face-a series of environmental and resource challenges that will severely test our present political and economic institutions. These challenges include (but are not restricted to) global climatic change, oil depletion, food supply security, water scarcity, and air and water pollution. Over the past century, the use of mineral resources and environmental sinks for wastes-both finite-have been concentrated in the 15-20% of the world population living in the industrial economies of the West. All this seems set to change, as much of Asia, with 55% of the global population, attempts to attain Western consumption standards. Already, China is the world's largest consumer of coal and concrete, and is second only to the US in Gross National Income and oil imports.

My talk first discussed these interconnected environmental and resource problems facing us, then considered the implications of the on-going shift to more global equality-at least at the national level. Finally, I look at the new policies needed to accommodate the needs of all humans in a sustainable manner on a finite planet.

In 1658, Archbishop James Ussher , of Armagh , calculated that the world was created on Monday, October the 12 th, 4004 BC. (His contemporary, Dr John Lightfoot of Cambridge refined the calculation, fixing the time at 9.00 AM.) What is more, Ussher calculated that Adam and Eve were driven out of the Garden of Eden on Monday, 10 th November, 4004 BC. (So they only got a month there—I hope they got their deposit back.) According to a well-known account, the eviction happened like this: ‘..and at the east of the garden of Eden he placed the cherubim and a flaming sword which turned every way, to guard the way to the tree of life’ (Gen. 3.24). They should all still be there, right? However, the garden of Eden was in southern Iraq . Genesis (2.10) also tells us that he river flowing out of the garden became four rivers, two of which were the Tigris and Euphrates . Maybe the cherubs and the flaming sword are the weapons of mass destruction George Bush is after?

So we’ve lost Eden . Can we ever get back? Do we want to? Here I’ll argue that today we don’t seem too interested in the tree of life. I’ll use climate change, oil, and water/food to illustrate the dangers ahead, but I could also have used species extinction or global epidemics as examples. We’re busy under-mining the support systems for life on this planet—and even of our economy—but it’s not something many wish to think about. Trivial pursuit is not just a board game—it’s a global obsession.

Climate change
We know that since the late 19th century, average global temperatures have risen by 0.6-0.8 deg C, most of it in the last few decades. Arctic sea ice is thinning, sea levels are rising, and glaciers in both tropical mountains and temperate lands are disappearing. (‘The Snows of Kilimanjaro’ are rapidly becoming ‘The Gravels of Kilimanjaro’—not a good name for a book?) Scientists now believe that the temperatures we are presently experiencing are the highest of the last millenium, and possibly, much longer. In fact, 16 of the highest annual temperatures ever recorded have occurred in the last 20 years. The higher and longer the rise in average global temperature continues, the more likely it is that the changes are real.

Are we the cause? Let’s start with the obvious. Days are warmer than nights. Summers are warmer than winters. Why? Clearly, astronomy explains both these facts. The earth spins on its axis every 24 hours, and the axis is inclined to the plane of its year-long orbit around the sun. Astronomical factors have also been invoked to explain the recent ice ages. In the early decades of the 20 th century, a Serbian Civil Engineering Professor, M. Milankovitch, refined an older theory explaining the ice ages by variations in the shape of the earth’s orbit, and in the tilt and wobble of the earth’s axis. These variations, caused by the gravitational influence of other planets on the earth, vary the distribution of the Sun’s insolation to the earth on very roughly 20, 40, and 100 thousand year cycles. The 100 000 year cycle seems to match the waxing and waning of the recent ice ages.

But astronomy can’t explain all temperature variations. The earth and the moon are the same distance from the sun, around 150 million km. But the average temperature of the moon is a chilly - 18 deg C, while the earth is a cosy + 15deg C. The reason for the difference is that the earth has an atmosphere, but the lighter moon has lost whatever atmosphere it had. And it is the heat-trapping constituents of the atmosphere—especially C²O—that are the reason for Earth’s warmth. Greenhouse gases in the atmosphere prevent some of the back radiation from Earth escaping into space. The result: gradual warming. So the greenhouse effect is real and already here—scientists often talk of an enhanced greenhouse effect.

‘But where are the snows of yesteryear?’, lamented the renaissance French poet Francois Villon. Rest easy Francois, they’re still here. Not in Paris , not in Melbourne . But in Antarctica lie the snows of a million yesteryears. We now know that over the past three million years or so, our planet has passed through a series of Ice Ages. Much of our information about Earth’s past climate has come from deep ice cores recovered from the Antarctic and Greenland ice caps. Drilling and recovering a continuous core of ice enables us to work out what climate was like thousands of years ago. The deeper you drill, the older is the annual snow layer which is compacted by the weight of overlying snow to form ice. From air bubbles trapped in the ice, scientists can determine the temperature at that time by isotopic analysis of the oxygen. They can also find out how much C²O was in the atmosphere, and the amount of dust in the air. The Vostok ice cores already give us a view of climate in the Antarctic over the past 700 000 years, and when drilling is completed, up to 1 000 000 years. These ice cores form an ancient library of the earth’s past history. But once these ice caps—particularly tropical glaciers—are destroyed by melting, the library is likewise destroyed.

As the science writer Fred Pearce puts it: ‘Nature doesn’t do gradual change’. This realisation came about for Earth scientists in the 1980s, when the results from the Greenland ice cap cores were published. What they found was that abrupt swings in climate—such as a 10 deg. C drop in temperature—could occur in as little as two decades. While our general circulation mathematical models do a good job of retrospectively predicting seasons on earth, they do a poor job of predicting such abrupt climate changes. So to understand climate change we need detailed studies of past climates, as well as mathematical models. Yet all our present policies regarding climate change implicitly assume that the change will be gradual, with plenty of warning. Consider the lowly toilet seat. The vexed question as to whether its natural position is up or down is one that will not be resolved in our lifetimes. The relevant point here is that compromise positions aren’t an option. The seat, like the light switch, has only two stable positions, ‘up’ or ‘down’. It may be the same with climate. For example, some scientists now believe that during the ice ages earth’s climate had two stable states. The transition wasn’t smooth—the earth’s climate simply jumped from one state to another.

James Hansen, a prominent earth scientist, thinks that the key issue for us is sea level change. How fast can ice sheets disintegrate? Hansen calculates that an additional one deg. C global warming is all we can afford if we are to avoid the break-up and melting of the Greenland ice sheet. Once melting is underway, it can’t be stopped. Building up ice sheets takes millenia, as snow is added year by year, but disintegration, once started, is assisted by several feedback mechanisms, and can occur fairly rapidly. But it might, or might not, take centuries. The trouble is that we can’t be sure what temperature change will occur for a given rise in C²O and other greenhouse gases because of the uncertain effects of feedbacks from water vapour, aerosols, and clouds. The disappearance of most of the 3 km thick Greenland ice cap would raise sea levels globally by about seven metres. Our ancestors may well have different lifestyles to ours, but even they probably won’t want to live under 7 m of water.

Global depletion of oil
Several centuries ago, people blamed others for their sick cow, or their hens that were not laying. With the rise of science, we now prefer natural explanations, right? Well, only sometimes. With the current oil crisis, we are still looking round for somebody to demonise. We can’t accept that we may be approaching the limits of what it is practicable to extract each year.

Two approaches were possible for blunting the oil price rises of the 1970s, one on the supply side, one on the demand side. First, oil exploration in non-OPEC countries, spurred by the higher prices, resulted in an increased supply from these sources, which included Alaskan and the North Sea oil. Now these and many other non-OPEC fields are in decline. On the demand side, substituting other fuels for fuel oil and other non-transport uses of oil reduced demand growth. For example, under 8% of world electricity in 2002 was generated using oil, down from 28.5% in 1980. Since only small further reductions in non-transport uses of oil can be expected, future increases in demand for transport will translate directly into oil demand increases.

World oil demand is again rising, with Asia mainly responsible for this growth. But will ever-increasing volumes of oil be available for purchase in the future? Here, expert opinion is divided. The US Geological Survey (USGS) is optimistic about future oil availability, and see non-conventional oil forming an increasing share of rising oil demand. Others, usually retired oil industry professionals, are sceptical. They agree with the USGS that the world is not about to run out of oil, although their estimates of future oil discoveries are much lower. One reason for their lower estimates: they claim that several OPEC countries greatly inflated their reserve figures in the 1980s to gain production quota.

But their main disagreement is with the rate at which oil, both conventional and non-conventional, can be produced. They argue that real annual additions to proved reserves of conventional oil are less than a third of annual production, and that production of non-conventional oil such as tar sands is both technologically demanding, expensive, and environmentally damaging. The recent news that Saudi Arabia, which has the world’s largest oil reserves and is the world’s largest producer, may have difficulty in maintaining even present production levels in the future, can only support the pessimists’ case. So maybe we just can’t extract ever-increasing amounts of oil each year. Even the oil optimists tacitly acknowledge that the lower-48 US oil production, which peaked in 1970, will continue its steady decline. What is true for one large oil region is true for the world as a whole. And in any case, the implicit assumption is that - assuming spare capacity can be made available - the Gulf states will will automatically supply what we want, rather than what they (or indeed all of us in our saner moments) want! Is it really a good idea to use ever-rising quantities each year, only to have to suddenly reverse this policy?

Water and food
Most of you will know Coleridge’s famous verse—or at least the second half: He was right. The world ocean covers around 363 million km 2, to an average depth of about 3.8 km—1.4 billion km 3of salt water. Freshwater is only 3% of all water, and most of it is locked up in the polar icecaps. Even so, humans have available over 52,000 km 3 of renewable fresh water annually, some 8500 m 3 for each of us. It sounds plenty, but it varies from very low or even zero for residents of a number of Middle-Eastern countries to 275 000 for each Congolese. For Australia , the average is about 26 000 m 3—three times the world average. But even for well-watered countries, water supply problems can arise because most freshwater is at the wrong place and the wrong time. That’s life eh? The flows are often far from population centres, and are often concentrated as floodwaters.

For this reason, the UN define water stress as occurring in countries using at least 20% of available renewable water. (An alternative definition uses an absolute value of 1700 m 3/year). We Australians can appreciate that: we only withdraw 3% of our renewable water, yet we have water restrictions in Melbourne . The fact that NT has plenty during the monsoon season is not very helpful in solving Melbourne ’s water problem. In 1990, around one third of the world’s people lived in countries that were water-stressed (using 20% or more of renewable resources). By 2025, that proportion is expected to grow to over 60% of the forecast, larger, population. Water shortages are already very serious. In northern China and in Iran , hundreds of villages are already being abandoned because of water shortages and desertification. Global warming will only make matters worse. Snow melt is an important source of river flow during the dry season in many areas. In effect, snow storage in mountains are free reservoirs. Higher temperatures will increase winter flows, but reduce dry season flows. Think of the Himalayas, which are the source of all of Asia ’s major rivers.

About 80% of global food needs are satisfied by grains, and it takes around 1000 tonnes of water to produce each tonne of grain. Trading grain is really a way of trading water. Any shortage of water then adds up to a shortage of food, especially grain. Globally, agriculture consumes nearly 70% of freshwater withdrawals. However, because urban uses of water, particularly manufacturing, add about 70 times more economic value than water used for irrigation, an ever-increasing share of water is going to cities in industrialising countries like China . Further, water researchers estimate that globally about 200 km 3 are overdrawn from aquifers each year, resulting in declining water tables. In brief, groundwater is being mined, not used sustainably. This volume of water is roughly equivalent to 200 million tonnes of grain—around 10% of global production. Grain harvests—unlike population—have failed to rise for the past four years. Indeed, globally, grain per capita peaked in 1984, and has been gradually falling since. It seems probable that rising populations, increased demand for animal feed grains, declining availability of non-polluted water for agriculture, and climate change will lead to progressively increasing difficulty in feeding us all—particularly if rising amounts of grain are fed to livestock.

Solutions: great and desperate remedies
What should we do about problems, and the others such as species extinction and global epidemics, which I haven’t discussed? Take global climate change. Even if global warming was caused partly or even mostly by (say) a long-term change in the sun’s output, our response would have to be similar. We would either have to try to adapt to an increasingly hotter earth, or else take steps to avoid excess warming. Table 1 shows the full range of possible options for achieving this. All these options have the same effect; they lower the ‘climate forcing’, and thus reverse the warming trend. Corporate leaders and their many friends in government would clearly prefer solutions that allow a ‘business as usual’ world to continue. Technical fixes are very attractive to them. In fact, the presumed availability of such fixes is a pre-condition for their acknowledging global warming as a serious problem.

Geoengineering as a technical fix is nothing if not ambitious. Using naval guns to shoot millions of tonnes of dust high into the stratosphere, or placing a giant reflective mirror of 1200 km or more radius in space could, in principle, counteract predicted future global warming. Not only are these fixes likely to be costly, but the risks involved are great. Different mathematical models would give different results for the outcomes of these actions. We won’t know the actual consequences with any certainty—until we do it. Further, given that the climatic benefits and costs would be unevenly distributed among nations, such deliberate planetary engineering would seem impossible to implement politically. And in any case, C²O would continue to accumulate in the oceans, where it is causing increasing acidity, with potentially serious effects on ocean ecosystems.

Table 1. Inventory of active methods for reducing energy greenhouse gas emissions.
No reduction in atmospheric C2O	Reduction in atmospheric C2O
Geoengineering	Carbon sequestration	Conversion to renewable energy	Reduction in total energy use
Counteract global warming by:   1. placing giant mirrors in space to lower insolation 2. placing dust or dielectric aerosols into the lower stratosphere.	Remove C2O from air by sequestering in: 1. soils, forests etc. 2. ocean surface layers fertilised with iron 3. deep ocean 4. disused oil/gas fields etc. 5. saline aquifers 6. silicate rocks converted into carbonates.	Replace fossil fuels by:   1. hydroelectricity 2. nuclear energy 3. biomass/bioenergy 4. wind energy 5. geothermal energy 6. solar energy 7. wave, tidal energy etc.	Cut energy use by:   1. raising efficiency of providing energy services 2. improving energy efficiency of devices.

We could also sequester carbon in soils and plants, or dispose of C²O in disused oil and gas fields, saline aquifers, or in the deep ocean. Sequestering carbon in soil and plants entails no collection costs, and would merely reverse soil/plant carbon losses of the past century. Deep ocean disposal has both high C²O collection costs, technical problems, and probable environmental risks. (Further, the law of the sea presumably prohibits ocean disposal at present.) In any case, carbon sequestered in soils, biomass, or oceans will sooner or later return to the atmosphere. For soils and plants, higher temperatures lead to increased respiration rates (C²O output) for plants and soil micro-organisms, which could overwhelm increased photosynthesis from higher atmospheric C²O levels. And any climate change that occurs will itself affect the ability of the oceans to store C²O. For aquifers and disused oil and gas fields storage time can be much greater, but some leakage will still inevitably occur. If we adopt sequestration as a long-term solution, stored C²O volumes will eventually be so large that even low rates of leakage will lead to total C²O annual emissions rivalling present levels. And we’re not good at keeping track of wastes. Already in the US , a number of nuclear waste dumps have been lost since the 1940s. And in post-USSR Russia ? The only permanent solution is to fix C²O in carbonate rock—an extremely expensive, and probably environmentally disruptive, undertaking.

Renewable energy sources (RE) offer another possible means of continuing ‘business as usual’ practices. They presently provide over 10% of world energy. Could they entirely replace fossil fuels? Not at anything like present prices, and perhaps not at any price. Without the prop of fossil fuels, renewable energy’s economics, and energy return on energy input, are much poorer than they are today. My own recent research suggests that RE on its own could provide only a fraction of the energy we’d need in a business as usual world in 2050. Eventually we will need to provide nearly 100% our energy from RE, but the total won’t be anywhere near projected energy trends.

We are left, I believe, with energy efficiency and conservation, together with RE. But some researchers think that in a growth-oriented economy such as ours, improving fuel efficiency can often be counterproductive for reducing overall energy consumption. Certainly, Australian overall energy efficiency (here measured by $ Gross National Income/primary energy consumption) is rising—but so too is total energy use! In an unrestrained growth economy, such as ours, any rise in energy efficiency in one sector (e.g. lighting or computers) will often be accompanied by new uses for these devices. (For lighting, more efficient compact fluorescent bulbs could lead to greatly increased use of security lighting, for example). Or, energy reductions could be offset by the continued flow of new energy-using products and services. There is scope for energy savings, even in a business as usual world. But sometimes energy efficiency can only be achieved by loss of convenience (public transport instead of cars), or by lower rates of industry production (energy-efficient rates of production can conflict with economic production rates).

Similarly, the scope for water efficiency improvement is less than was previously thought. Although most irrigation water isn’t taken up by the intended crops, it isn’t necessarily wasted; it either replenishes the water table, or is returned to rivers downstream where some other farmer can use it. Only excess evaporation is truly wasted. Another way to beat water shortages is to start desalinating the Ancient Mariner’s 1.4 billion km 3 of sea water. It’s already done in over 100 countries—mainly ME and small island nations. But now China , the US and even the U.K. ( London ) have started desalinating, or plan to start soon. Desalinating water involves large energy (and money) costs. Again, we could try to solve our oil reserves problem by tapping heavy oils, tar sands or shale oils. The latter two have to be extracted by mining rather than pumping, so money—and environmental—costs are high. But the real problem is greenhouse gas emissions—per litre of petrol in your tank, emissions increase by 30-40%. As with desalination, we solve one problem by creating another.

Solutions: political approaches
Politics means different things to different people. For many, it means what Johnny and Mark said. (What Marx called ‘the normal cretinism of parliamentary politics’.) Here I’ll concentrate on just one aspect of the social/political world relevant to my argument—the changing access of the world’s people to its resources and sinks over the past three centuries. Recently, an eminent economist (Prof. Angus Maddison) published his estimates of GDP per capita for various regions of the world, going back to year 1700. (For the pedants, all the figures are in 1990 US dollars, using purchase parity pricing, and GDP stands for Gross National Product, the value of all goods and services produced in a country in a year.)

I’m not sure how he arrived at $531, not $530, or even $500, for India in 1700. But, even allowing for such dubious precision, it’s very clear that world inequality increased from 1700 to 1978. In fact, real incomes in India and China in 1952 were the same as two and one half centuries earlier. China ’s per capita income was the same as the US in 1700 (i.e. 100% of US), but by 1978 was down to 5.4% of the US level. Such huge differences in income were mirrored in access to material goods. Take cars. In the early 1950s, fully 80% of the world’s cars were in North America . Even in 2000, car ownership was far higher in the OECD; in the US about 700 per 1000 persons, and about 500 in both Australia and Japan , compared with 5 in India and 7 in China , and less than one in Bangladesh .

Table 2 Regional GDP/capita, 1700-1995, $ US 1990 PPP.
Country	1700	1952	1978	1995
China	600	537	979	2 653
India	531	609	972	1 568
Japan	600	2351	12 581	19 720
Europe	870	4 374	10 860	13 951
United States	600	10 645	18 251	23 377
Russia	600	2 928	6 565	4 383
World	604	2 268	4 382	5 194

A couple of decades ago, and even today for tropical Africa , it was common for concerned industrial country people (like us?) to point out these inequalities, and to argue for policies to remedy them. Well, guess what? In recent years, China , and then India , got tired of waiting for our charity. Can you blame them? Instead, they are following the path that first Japan , and then places like S. Korea, Hong Kong, and Singapore took to industrialisation. (We’ll concentrate on Asia, but Eastern Europe may also be at last starting to catch up with the West. In contrast, tropical Africa continues to fall further behind the industrial countries, and Latin America is not improving its position.)

But it’s one thing for Hong Kong and Singapore to rise to Western standards of living—there are only 10 million there. But for all Asia —home to around 55% of the world’s 6.2 billion population—that’s another matter. Any way you do the math, it doesn’t work out. Consider oil again. In the year 2002, Japan and Australia both used 1.9 tonnes of oil per person. For China , the corresponding figure was only one-tenth of this, 0.19 tonnes. If all of Asia in 2002 had the Japanese/Australian per capita oil consumption level, total Asian consumption would have been 6.5 billion tonnes, compared with actual 2002 global consumption of only 3.5 billion tonnes.

An official Chinese government forecast predicts that the demand for cars in China will rise to over 20 million annually by 2020, with total car ownership then 156 million. In much of Asia , the middle class is growing rapidly, and with it the aspiration (and the income) to own a car. Chinese, Indians, and other Asians are just as car-crazy as we are. Further, most Asian governments strongly support an indigenous car industry, seeing it as a cornerstone for their industrialisation strategy—just as OECD countries did.

So what’s going to happen? Let’s look at global climate change. Perhaps ‘Plan B’, which is supported by the UK and the UNEP, among others, will be implemented. This would replace the near-defunct Kyoto Protocol by a plan where all the world’s countries converge on 1.1 tonnes C²O per capita. If you lived in Chad , that might sound like plenty, but Australia ’s per capita emissions of fossil fuel C²O are about 18 tonnes. We have some belt-tightening to do! Similarly, the Association for the Study of Peak Oil are promoting a quota system for oil for each country—both to make supplies last longer so that the transition can be managed more smoothly, and so that the oil wars can stop. But even without quotas, Asia ’s rising standards of living will ensure that they can buy increasing shares of oil available.

What should individual countries, such as Australia , do to improve ecological sustainability? One possible approach to moving us closer to a sustainable consumption level is to raise prices for scarce resources or sink capacities. It’s the market solution! Take transport again—and look at our large cities, like Melbourne . Raising petrol prices enough would lower oil use to any level we wanted—but it would also give us with a progressively nicer class of motorist! It turns out that in our large cities, the lower your income, the further (on average) you live from the city centre. (Some of you will remember that the reverse was true in the 1940s). Further, outer area residents have greater travel needs—their work trips are much longer than innner suburban residents, for instance. So this solution would be at the expense of local equity. But what if we worked on travel time instead? Everyone gets only 24 hours a day—rich and poor. What if we imposed massive speed reductions (30km/hr maximum), stopped further arterial road-building, and closed the city centre off to traffic? Public transport and walking would look much more attractive. We could even pay for our public transport systems by having a household tax modelled on our rates system. And, of course, we could just travel less. In the interests of more equity within our country, other non-monetary solutions will be needed for our other resource/sink problems. Some increase in water prices, yes, but water restrictions as well. Perhaps a sliding scale for utility prices, with a basic amount at low cost? We’ll need to look a lot more at rationing and less at market-based remedies for our growing resource/sink crises.

All this may sound very pessimistic. (We all adults here; if you want a happy ending, catch up with storytime at your local council library!) But in any case it’s only pessimistic if you see ever-rising GDP as a necessary condition for human welfare. It probably is necessary for corporate welfare. So, I’m arguing that all we inhabitants of the Earth will need to walk on it with a lighter tread. And I’ve argued that the West’s dominant use of the world’s limited resources and sinks is now being challenged–morally and economically—by Asia . So, to live in harmony with each other, we’ll have to share resources more equally. And to live at all, we’ll have to live in harmony with the Earth’s other millions of species. Remember Eden —the lion and the lamb lying down together? A mine canary dying is not just a concern for that small bird’s family and friends—the well-being of other species is necessary for our survival.

The twin realities of Asian economic growth, and a deteriorating environment which cannot be ignored much longer, ensure that large changes will inevitably occur. Are you ready?

This talk was presented by Patrick Moriarty at a U3A Melbourne Forum on the 30 September, 2004 & is included in the U3A online archive with his kind permission