The Best Australian Science Writing 2013 (8 page)

Darwin was intellectually courageous and determined, but he was not a righteous ideologue. More than anything, Darwin seemed driven by diligent curiosity. As a student at Shrewsbury School, he wandered off to collect beetles; at Edinburgh University, he preferred looking in fishing nets to looking at surgery.

Darwin's poor academic results reflected his boredom with
the syllabuses of medicine and theology, but also his fascination with plants and animals.

Darwin eventually left for Cambridge, discovered a mentor in botany, and began his illustrious career as a naturalist. What marked his success was this curiosity, combined with patience and doubt. Throughout his boyhood, youth and middle age, when Darwin undertook his exhaustive, exhausting study of barnacles, he was always chasing more evidence – not to shore up a predetermined conclusion, but to enhance and enrich his ideas.

Curiosity drove Darwin, but it did not blind or hurry him. Note his cautious excitement, as he writes to a colleague, in 1844, that he is ‘almost convinced' that the species change – they are not the eternal, perfect works of God. ‘It is like confessing a murder,' he adds.

In an age often driven to celebrate or lament scientific power, this is a valuable reminder of the best scientific motives. Darwin was driven not by greed, egomania or devilish mockery, but by inquisitiveness, doubt and courage – each balancing the other.

The first virtue drew him in, fascinated by barnacles, and other perplexing problems. The other virtues stopped him from solving these problems too soon, or denying the solutions he discovered.

In this, Darwin was not a super-genius, blessed with perfect logic and an easy mastery of all sciences. He was a well-educated English gentleman, raised in a wealthy, free-thinking family, who combined ardour with persistence and scepticism. In so doing, he never let enthusiasm become zealotry, or speculation become doctrine.

This remains an important lesson today. The Darwinian revolution did not begin with hatred of religion, or with hubris and arrogance. It was a cautious love of truth, not a flaming hatred of superstition or myth – they are not necessarily the same urge.

And just as importantly, with training and drive, we are all
able to observe carefully, analyse precisely, and speculate boldly; we can exercise our minds, instead of taking up church dogma or ideology. We can all say, with Darwin, ‘I think' – and genuinely do so.

Creationism

Modest, not!

Earthmasters: Playing God with the climate

Clive Hamilton

As the effects of global warming begin to frighten us, geoengineering will come to dominate global politics. Scientists and engineers are now investigating methods to manipulate the Earth's cloud cover, change the oceans' chemical composition and blanket the planet with a layer of sunlight-reflecting particles. Geoengineering – deliberate, large-scale intervention in the climate system designed to counter global warming or offset some of its effects – is commonly divided into two broad classes. Carbon dioxide removal technologies aim to extract excess carbon dioxide from the atmosphere and store it somewhere less dangerous. This approach is a kind of clean-up operation after we have dumped our waste into the sky. Solar radiation management technologies seek to reduce the amount of sunlight reaching the planet, thereby reducing the amount of energy trapped in the atmosphere of ‘greenhouse Earth'. This is not a clean-up but an attempt to mask one of the effects of dumping waste into the sky, a warming globe.

Diligent contributors to Wikipedia have listed some 45 proposed geoengineering schemes or variations on schemes. Eight or ten of them are receiving serious attention. Some are grand in
conception, some are prosaic; some are purely speculative, some are all too feasible; yet all of them tell us something interesting about how the Earth system works. Taken together they reveal a community of scientists who think about the planet on which we live in a way that is alien to the popular understanding. Let me give a few examples.

It is well known that, as the sea ice in the Arctic melts, the Earth loses some of its albedo or reflectivity – white ice is replaced by dark seawater which absorbs more heat. If a large area of the Earth's surface could be whitened then more of the Sun's warmth would be reflected back into space rather than absorbed. A number of schemes have been proposed, including painting roofs white, which is unlikely to make any significant difference globally. What might be helpful would be to cut down all of the forests in Siberia and Canada. While it is generally believed that more forests are a good thing because trees absorb carbon, boreal (northern) forests have a downside. Compared to the snow-covered forest floor beneath, the trees are dark and absorb more solar radiation. If they were felled the exposed ground would reflect a significantly greater proportion of incoming solar radiation and the Earth would therefore be cooler. If such a suggestion appears outrageous it is in part because matters are never so simple in the Earth system. Warming would cause the snow on the denuded lands to melt, and the situation would be worse than before the forests were cleared.

More promisingly perhaps, at least at a local scale, is the attempt to rescue Peruvian glaciers, whose disappearance is depriving the adjacent grasslands and their livestock of their water supply. Painting the newly dark mountains with a white slurry of water, sand and lime keeps them cooler and allows ice to form; at least that is the hope. The World Bank is funding research.

Another idea is to create a particle cloud between the Earth
and the Sun from dust mined on the moon and scattered in the optimal place. This is reminiscent of the US military's ‘black cloud experiment' of 1973, which simulated the effect on the Earth's climate of reducing incoming solar radiation by a few per cent. Consistent with the long history of military interest in climate control, the study was commissioned by the Defense Advanced Research Projects Agency, the Pentagon's technology research arm, and carried out by the RAND Corporation, the secretive think tank described as ‘a key institutional building block of the Cold War American empire'. I summon up the black cloud experiment here to flag the nascent military and strategic interest being stirred by geoengineering. The attention of the RAND Corporation has recently returned to climate engineering.

In 1993 the esteemed journal
Climatic Change
published a novel scheme to counter global warming by the Indian physicist PC Jain. Professor Jain began by reminding us that the amount of solar radiation reaching the Earth varies in inverse square to the distance of the Earth from the Sun. He therefore proposed that the effects of global warming could be countered by increasing the radius of the Earth's orbit around the Sun. An orbital expansion of 1–2 per cent would do it, although one of the side effects would be to add 5.5 days to each year. He then calculated how much energy would be needed to bring about such a shift in the Earth's celestial orbit. The answer is around 10
³¹
joules. How much is that? According to Professor Jain's calculations, at the current annual rate of consumption, it is more than the amount of energy humans would consume over 10
²⁰
years, or 100 billion billion years (the age of the universe is around 14 billion years). This seems like a lot, yet he reminds us that ‘in many areas of science, seemingly impossible things at one time have become possible later'. Perhaps, he speculates, nuclear fusion will enable us to harness enough energy to expand the Earth's orbit. He nevertheless counsels caution: ‘The whole galactic system is naturally
and delicately balanced, and any tinkering with it can bring havoc by bringing alterations in orbits of other planets also.'

The caution is well taken, although the intricate network of orbital dependence has stimulated another geoengineering suggestion. The thought is to send nuclear-armed rockets to the asteroid belt beyond the planets of our solar system so as to ‘nudge' one or more into orbits that would pass closer to the Earth. Properly calibrated, the sling-shot effect from the asteroid's gravity would shift the Earth's orbit out a bit. Of course, if the calibration were a little out, the planet could be sent careening off into a cold, dark universe, or suffer a drastic planet-scale freezing from the dust thrown up by an asteroid strike.

Some of these schemes seem properly to belong in an HG Wells novel or a geeks' discussion group, and too much emphasis on them for the delights of ridicule would give a very unbalanced impression of the research program into climate engineering now under way. Serious work is being conducted on schemes to regulate the Earth system by changing the chemical composition of the world's oceans, modifying the layer of clouds that covers a large portion of the oceans and installing a ‘solar shield', a layer of sulphate particles in the upper atmosphere to reduce the amount of sunlight reaching the planet. There are some who believe that we will have no choice but to resort to these radical interventions. How did we get to this point? The simple answer is that the scientists who understand climate change most deeply have become afraid.

Promethean dreams

Everyone is looking for an easy way out. The easiest way out is to refuse to accept there is a predicament. Another is to hope that the problem is not as bad as it seems and that something will come along. The technofix of geoengineering is a third way out and an emerging lobby group of scientists, investors and political
actors is giving it momentum. Yet the appeal of climate engineering runs deeper, for as an answer to global warming it dovetails perfectly with the modernist urge to exert control over nature by techno logical means.

Scientists, entrepreneurs and generals have long dreamed of controlling the weather. The development of computers and the accumulation of weather data using satellites have prompted a new and higher phase of dreaming. In 2002 the American Meteorological Society published a NASA-funded study titled ‘Controlling the global weather'. The author, Ross Hoffman, foresees the creation of an international weather control agency within the next three to four decades. ‘Just imagine,' he enthused, ‘no droughts, no tornadoes, no snowstorms during rush hour etc.' Control would be possible, the argument goes, precisely because weather systems are chaotic. Chaotic systems are very sensitive to small perturbations, so, if we can identify and then control those perturbations, then we can control the weather: ‘since small differences in initial conditions can grow exponentially, small but correctly chosen perturbations induce large changes in the evolution of the simulated weather'. He did not dwell on the implications of small but incorrectly chosen perturbations.

Controlling one country's weather is not possible without affecting that of others, so the only way forward would be a global weather control system. Without close collaboration, Hoffman warns, there may be ‘weather wars'. Among the perturbations that could serve as control mechanisms for global weather he identifies the timing and location of aircraft contrails, solar reflectors that regulate the amount of sunlight and an enormous grid of fans that could redirect atmospheric momentum. A more recent scientific paper explores the possibility of a control strategy for El Niño, the periodic warming of central and eastern Pacific currents that causes drought in Australia and floods in South America. It too looks for leverage in small disturbances
with large effects, the most promising lever being alteration of sea surface temperatures in the eastern Pacific through cloud brightening.

Stephen Salter, an engineer and principal researcher in marine cloud brightening (an approach that involves enhancing the reflectivity of the low-lying clouds that cover up to a third of the oceans), is convinced that we will soon know everything there is to know: ‘Noise is only a signal which you have not learned to decode yet.' He is excited by the prospect of total control of the Earth's climate, and entertains plans of domination that would do Dr Strangelove proud. He defends further research with the claim that:

We might discover that to get more rain at Timbuktu in August but less rain during Wimbledon you should spray to the west of Cape Verde island from mid April to mid May and stop all spraying south of Kerguelen during January and February. However spraying south of Tasmania from June to December never affects anywhere north of Hong Kong. By linking the strength of the beneficial effects with observations of the weather patterns and spray planning we may eventually develop sufficient understanding to allow tactical or closed-loop control which could respond to other more random perturbing influences and make everyone happier with their weather.

This kind of technological hubris, although not often expressed so brazenly in public, colours the advice governments are beginning to receive from geoengineering researchers. The idea is taking root that geoengineering could be used not just to counter some of the effects of global warming, but to manipulate permanently the planet's weather system to suit our desires, or at least the desires of those who turn the knobs. To this end, climate
engineers are beginning to talk about employing not one but a suite of interventions designed to tailor the climate. So stratospheric aerosol spraying might be used to cool the globe overall, while cloud seeding may be undertaken to finetune other environmental goals, such as preserving coral reefs, ‘hurricane emasculation' and restoring polar ice caps. Engineering the global climate thus becomes an optimisation problem.