Reflections on Flannery’s National Library lecture (part 2)

It is greatly to Flannery’s credit that, faced with daunting conclusions on this scale he habitually finds grounds for positive thinking and action. That was true of The Weather Makers which ended with a call to arms for household action, still one of the main fronts of climate strategy. In 2006, as the emerging data bean to indicate the dramatic acceleration of the warming trend, his scientific training led him to a pessimistic assessment and into advocacy of nuclear technology as a last line of defence–a not inconsiderable reversal for him, given his long-held green convictions. Even now he seems to be prepared to keep the nuclear option (as in technology, not war, although it is difficult to disentangle the two) on the agenda. But with the publication of Hansen’s paper Flannery’s focus has moved. The critical challenge presented by the paper, and a startlingly new one, is not how to prevent emissions growth, which is the only potentially positive contribution of nuclear technology (and even then, in terms of life-cycle and embedded energy, a matter of continuing controversy). It is how to extract carbon from an already overloaded atmosphere, a task to which nuclear technology can make no contribution. It becomes necessary to turn to other strategies and technologies, some very old, some new, some well understood and tested, others still being proved. Whatever works, is the blunt criterion.

To begin with, Flannery, following Hansen (as he does throughout the lecture) turns to the fuels that are the mainstay of modern economies: coal and oil. There is no doubt coal-fired energy is the single greatest contributing technology to greenhouse gases among all technologies. That is particularly true of electric power stations that burn low-grade brown coal. These are common in the developing world; although Australia, too, to its shame, has its share of them. In this context it is worth remembering that China is reported to be commissioning a new, mid-sized power station, fired by coal, every week. The Flannery/Hansen position is that coal technologies must be phased out, but that this is unlikely to occur at the pace which the new models indicate is required. Weight is therefore given to carbon sequestration as a means to minimise the impacts. Under this proposal no new coal-fired power stations would be built without support from the sequestration technology.

In this, many would argue, Flannery/Hansen have for once allowed wishful thinking to override scientific, or even practical, judgement. There is no proven sequestration project operating anywhere in the world. There are serious challenges facing both CO2 extraction from the coal-firing process and its concentration prior to injection and storage. There are equally serious questions concerning the geological feasibility of storing these emissions for the very long periods of time–far in excess of any social scale we can contemplate–that a coherent climate change policy will require. While not as dangerous to long-term human health as nuclear waste, these stored emissions are nevertheless potentially lethal. Natural leakage of carbon monoxide is known to have been responsible for many deaths. On the timescale of the action required by the Flannery/Hansen position, there is serious doubt that carbon sequestration technology can be developed, tested, proven and safely deployed. It may well be that it cannot be developed at all. 

Oil and gas, the other main fossil fuel culprits, are to be handled by economic instruments, specifically a carbon tax. Weighted against the chief alternative, an emission trading scheme, I agree that a carbon tax is to be preferred. Any emissions trading scheme is complex and expensive to mount, as the EU experience with carbon trading has shown. Special exemptions for exposed industries, such as those now being sought, with flagrant greed and self-interest, by companies associated with the Business Council of Australia, threaten to eviscerate the effectiveness of the proposed trading scheme. A carbon tax, in contrast, is simple and inexpensive to implement. Moreover, it yields a ‘double dividend’, collected tax revenue which can be applied to cushion impacts on the most disadvantaged–the poor and the economically marginalised–and to further the development of renewable technologies. 

Either way, whether economic instruments can lead to material reductions in greenhouse gas levels or not is yet to be seen. Four years of the EU emissions trading operation has not produced unambiguous evidence of reduced emissions in the EU countries trading through it. On the other hand, there is well-documented evidence of financial windfalls gained by companies which were over-allocated emissions permits in the initial handouts and quickly sold them. Carbon offset mechanisms have proved an ecological and regulatory minefield. There is a long way to go before effective trading in greenhouse gases can be said to be in place anywhere in the world. To extend this task to the development and implementation of a truly global emissions trading scheme–the requirement for handling global CO2 levels, since the atmosphere doesn’t recognise national borders–is a formidable challenge to the global community, to say the least of it. 

Renewable energy technologies, particularly wind and solar, are supported under the Flannery/Hansen proposal. In places like Australia, geothermal energy and its associated technologies offer particular promise. There is emerging evidence that, at the household level, wind and solar technologies can be effective. What is would take for these technologies to make an impact on business and industry–by far the greatest users of energy–is not at all clear: the tradeoffs in land use that would require are daunting to contemplate. 

This tripartite approach–carbon sequestration, economic instruments, renewable energy technologies–constitute the main ramparts that Flannery, following Hansen, proposes to build against the tide of increasing greenhouse gas emissions. On the other side of the equation, the extraction of existing CO2 from the atmosphere, Flannery/Hansen offer two strategies. The first centres on the ability of trees to take up and store carbon as they grow. This is hardly a new strategy, but Flannery/Hansen give it new urgency. Their focus is on tropical forests, because it is there that growth is most rapid and the rate of carbon uptake is consequently greatest. The two arms of the strategy are thus the reduction and eventual (but sooner rather than later) halting of tropical deforestation, particularly in Indonesia and Latin America; and the replanting of the vast areas of degraded tropical forests. This strategy doesn’t exclude other forest ecoregions, such as the Taiga: a recent Australian National University study found maximum levels of carbon storage in Australia’s old growth forests, many of which are in temperate (for the time being) zones. But, other things being equal, Flannery/Hansen are pointing out that the best outcomes, in terms of carbon extraction and storage, for a given level of resource expenditure, is a tropical forest strategy. 

Alongside this well-known mechanism, Flannery/Hansen place considerable weight on a relatively new application of a process called pyrolysis. Essentially this technology is a method of burning carbon under controlled conditions to produce charcoal (‘biochar’–see Cornell research). Unless further heated, charcoal, Flannery points out, is inert and stable, and can be buried with impunity; in fact, properly crushed, charcoal is known to improve soil structure and fertility. Flannery paints a picture of a future crop harvest, where a pyrolising unit is being towed behind a harvester to render stubble into charcoal, instead of burning it off. Experiments are said to be under way in large-scale pyrolising, such as that associated with municipal waste-water systems. It is, however, a technology that is still in its early stages, and its scope of application is far from certain. Even its energy budget is yet to be established finally: one needs to be confident that it is, in fact, a technology that reduces, not increases, net emissions before it is widely deployed. 

Both tropical forests and pyrolising strategies are clearly in the right direction. However, if Flannery’s numbers are right, at best they offer limited CO2 capture, relative to the requirement. Even if CO2 production is reduced by the other three strategies, it is not at all evident that together they will effect the closing of the gap between production and capture that a stable global CO2 budget demands; certainly, if Hansen’s projections are correct, not in time.

Reflections on Flannery’s National Library lecture (part 1)

A few days ago I listened to a radio replay of the Kenneth Meyer lecture given recently at the Australian National Library by Dr Tim Flannery (webcast here). The topic was, of course, climate change. Flannery has been one of the most persuasive and articulate leaders of the international public discourse on climate change over the past several years. His book The Weather Makers, published in 2005, was one of the first to assemble the scientific evidence on climate change and present it to the general public. In retrospect it is a little shocking to realise first, how long it took for such an account to appear, given what is now becoming clear of the scale and impacts of climate change; and second, how much more critical the picture is now, only three years later.Flannery is well situated to educate the general public on the emerging scientific consensus about climate change. His academic training as a palaeoecologist places him at the centre of the many disciplines required to make sense of the complex scientific data and analysis. His gifts as a speaker and writer are considerable: he is able to present for the general audience the main lines of scientific evidence and its key ideas and findings with clarity and power. A review of The Weather Makers described it as “the Silent Spring of our time.” The reference is appropriate, both in presentation style and in content. After a battering by the scientific critics Carson’s book eventually became the first authentic statement of the modern environment movement, and is still one of its standard-bearers. Flannery’s work on climate change is still in the battering mode, under attacks by a new generation of scientific critics and commercial interests. One can only hope that he, too, with colleagues like the American James Hansen, will ultimately prevail. The alternatives don’t seem to bear thinking about.

Flannery, however, does think about them, explicitly and unblinkingly. It’s not easy to tread the line between realism and hyperbole, and there would be those who would observe some swerving and exploration of blind alleys by Flannery over the past few years. Last year, appointed Australian of the Year by John Howard, in a quixotic (or calculated) political moment, appeared difficult for Flannery, caught between a government fixed on denying climate change and the serious implications of the newly emerging scientific evidence: his public statements mirrored his shock and desperation, as governments around the world continued to dither. Now, however, free of the title and its constraints, and perhaps having had time to assimilate the confronting scientific evidence, he seems to have found his public voice again. This was a fine lecture, important in the public discourse, for both its realism and purpose. On the side of realism, I am reminded of Jack Welch’s business dictum, “See the world the way it is, not the way you want it to be.” That is not to discount the power of vision and imagination but to recognise that we can only start from where we are. And where we are in terms of climate change, Flannery pointed out, is considerably more serious than had been thought even two years ago. The world (or at least that part of it which has concluded that climate change is real and worth worrying about) has been relying for its scientific appraisal on the modelling and projections of the UN International Panel for Climate Change (IPCC). The IPCC has been subjected to sustained attacks by those who believe it has vastly overstated the dimensions and risks of climate change, particularly anthropogenic climate change. Its work is now, Flannery observed, under new challenge, this time by new evidence from present and past events, and not for overstating but for understating. Climate change appears to be happening much faster than any of the IPCC scenarios had contemplated, moving the timetable for urgently required action forward by many decades.

Flannery highlighted two new pieces of evidence in support of this conclusion, one from the present and one from the past. From the present comes the dramatic acceleration of the melting of the Arctic ice. Because of the concentration of the effects of temperature rise at the Poles, the Artic ice, much less extensive than the Antarctic ice, was always predicted to exhibit early warning signs of global warming. The diminishing boundary of summer ice has been observed for at least a decade. The trend, however, accelerated markedly in 2005-2006, and in 2007 jumped to a level that the IPCC models predicted would not occur for some decades. That level has been reached again this year, with the North-West and North-East Passages open and joined for the first time in human history. It now appears likely, from a scientific point of view, that the Arctic ice has crossed the much-anticipated tipping point, where the lower albedo of open water allows the absorption of so much more heat that the winter ice must reform a smaller and smaller scales until it disappears. There now seems to be no intervention that can reverse this feedback mechanism, and the disappearance of the Arctic ice is predicted in a matter of years, not decades. The range of impacts this remarkable event will have on the earth’s biophysical system is still largely unknown.

In a general sense this unpredicted warning points to the central problem of the IPCC modelling, one which the modellers themselves have always recognised. The world climate system is large and immensely complex and operates at the largest scale of global systems. Modelling even the mainly linear evolution of these systems is associated with wide-ranging uncertainties. The non-linear elements of these systems are even more difficult to identify and model. It had always been supposed that there were many more feedback mechanisms operating in the global climate system than had be captured in the IPCC models. In addition, unidentified linkages between sub-systems almost certainly exist. It now appears that these hidden factors are much more widespread and important than had been assumed. The feedback mechanisms seem to be overwhelmingly positive; that is, strengthening of trending directions. The Arctic ice is a graphic demonstration of the need to reconfigure the IPCC models to account for more powerful and accelerated effects.

The second new piece of evidence assembled by Flannery comes from the work of James Hansen and his colleagues, associated with the NASA/Goddard Institute for Space Studies, New York. Hansen, as those who have followed climate change for the past two decades will remember, was the first climate scientist to draw attention to the scale and risks of anthropocentric global warming in his 1988 testimony to Congress. As is also well known Hansen was one of those scientists singled out for attention by the successive Bush administrations in their attempt to diminish the impact of the emerging scientific consensus of the reality and seriousness of anthropocentric climate change. In June of this year Hansen and his colleagues published a paper out of the NASA/Goddard Institute entitled “Target atmospheric CO2: where should humanity aim?” The paper examines the climatic history of the earth over the past 65.5 million years. It conclude that the climate system is more sensitive to CO2 accumulation than had previously been thought. Critical to the analysis are ‘slow’ climate feedback processes that are not included in most climate models, but which profoundly affect predictions. These are such processes as ice sheet disintegration, vegetation migration, and greenhouse gas release from soils, tundra or ocean sediments.

Until now an upper limit of 2 degrees centigrade of global warming has been generally thought adequate to limit its impact. Hansen has argued for an upper limit of 1.7 degrees centigrade to avoid irreversible ice sheet and species loss. This has implied a maximum CO2 level of 450 parts per million. Currently we sit at 385 parts per million. The indication of this analysis has been that, although serious and urgent, there is still time to act to prevent the tipping point being reached and seeding dangerous climate change.

The remarkable and challenging conclusion reached by Hansen and his colleagues in the June 2008 study is that, due to the slow feedback impacts, these numbers are probably not right. The evidence from their study of paleoclimatic systems is that 350 parts per million of CO2 seems likely to be closer to the upper limit of safety, if irreversible ice sheet and species loss, with all their attendant impacts on humanity, are to be avoided. At that figure the global system is already in the dangerous zone—past the tipping point. The first critical question is now for how long this post-tipping point level can be maintained before becoming irreversible. The second is not now only how to slow emissions growth, the target adopted by most of the world’s nations who have recognised the need to set emissions policy, for under Hansen’s analysis this must lead to inevitable disaster. It is how to take existing CO2 out of the atmosphere, as fast as possible, while limiting the current net CO2 balance to zero. The stakes, to indulge in severe understatement, have been raised, for the continued well-being of humanity, and of the species who share the planet with us.

Ian Lowe’s ‘Quarterly Essay’ on climate change and the nuclear option

Ian Lowe’s Quarterly Essay entitled Reaction Time: Climate Change and the Nuclear Option is a well-informed, well-reasoned and timely contribution to the current debate. He brings an unusual level of credibility to the debate. He is an engineer and physical scientist by training, with a doctorate in physics, and currently emeritus professor of science, technology and society at Griffith University–an orientation which fits him exceptionally well to handle the multi-disciplinary character of the issue. Interestingly, his early academic years in the UK in the 1970’s saw him as a supporter of nuclear power, and a participant in early policy reviews. In this essay he recounts the accumulation of data and experience that lead him to the opposite position. He is now President of the Australian Conservation Foundation, and has a clear position against nuclear power as a solution to global warming.

His essay covers a lot of ground, and is worth reading by anyone who wants an informed, although clearly–and unapologetically directed–view of the issues. He reviews the energy demands of the world, centreing on the emerging peak of oil availability, and outlines the global dilemmas implicit in this trend. In this he doesn’t retreat from a consideration of quality of life and well-being issues, or of distribution impacts between the developed nations and the poor of the world. He notes some important precursors in attempts to restructure societies in more sustainable energy directions (such as Alberta, Canada).

He summarises the evidence for climate change–evidence which he regards as incontestable–and the generic technical solutions: cleaner fuels and energy efficiencies. He then moves to a consideration of the nuclear option. He takes head-on the idea of nuclear technologies as the only ‘clean’ technology capable of addressing global warming. He covers the true costs of nuclear power, which he argues make it uneconomic; the world-wide retreat from nuclear reactors; the long time lags needed to bring nuclear energy on line; the threat from nuclear accidents, such as Chernobyl, and of nuclear weapons proliferation; the almost inconceivable lengths of time over which nuclear waste will have to be stored effectively, and the lack of a technology to do so; and the problems of low-grade uranium ores:

“Total life-cycle analysis has concluded that fuelling nuclear power stations from lower-grade ores actually releases more carbon dixoide per unit of delivered energy than burning gas. . .there is no doubt that the fuel energy, consequent greenhouse emissions and the dollars needed to produce uranium all increase rapidly as the ore grade declines.”

(This is a point referred to in my posting of August 20).

Lowe looks in some detail at the techical problems associated with economic projections over the long periods required by the analysis of energy options, and particularly the problem of discounting, which places far greater weight on the well-being of present as distinct from future populations. He analyses incisively the rather ludicrous policy developments in Australia, as the federal government has attempted to marshall some kind of ‘expert’ opinion in favour of nuclear power, in support of its economic objectives. He flags the agenda for nuclear enrichment in this country and the dangers inherent in it. He dissects the current policy, of both parties, to sell uranium into a deeply unstable international political environment. He notes the real possibility that Australia is headed for the role of a nuclear waste dump for the US.

Against this Lowe promotes the growing credentials of wind and solar power to provide an increasing proportion of the world’s energy requirements at reasonable costs. Notably, he points out that the current level of energy demand is not a given which has, at all costs, to be met: at the level of material prosperity enjoyed by this country in the 1960’s, he argues, a sustainable world could be equitably enjoyed.

Although this is a polemical document, its marshalling of arguments against the nuclear energy option and in favour of renewable energy options is an important statement, and one that, under the present push by the nuclear industry to rebadge itself as clean and green, to what it hopes will be a compliant and intellectually cowed society, is greatly needed. It should be widely read.

Link to The Quarterly Essay here.