With Speed and Violence: Why Scientists Fear Tipping Points in Climate Change (35 page)

Hansen also advocates action on soot, which he calculates to be the third biggest man-made heating force in the atmosphere. Soot, as we saw in Chapter 18, has a local cooling effect but a wider and more considerable warming effect. It sticks around in the atmosphere for only a few days, but while it is there, its effects are large. Action against soot and methane would not stop global warming. But it would give the world time to introduce measures against the chief culprit: carbon dioxide.

KYOTO POLITICS

The Kyoto Protocol, signed in 1997, was the first, tentative step toward implementing the Rio pledge to prevent dangerous climate change. Some forty industrialized nations promised to make cuts in their emissions of six greenhouse gases, including the "big two": carbon dioxide and methane. Different countries accepted different targets, and the countries of the European Union later internally reallocated theirs. Those cuts averaged about 5 percent, measured between 19go and the first "compliance period," which runs from 2008 to 2012. The protocol included various "flexibility mechanisms" aimed at making more effective use of cleanup investment funds. They allow countries to offset emissions by investing in cleanup technology abroad and in planting trees to soak up carbon dioxide from the air, and to trade directly in pollution permits.

The protocol did not impose targets on developing countries, because their emissions per resident are mostly much lower than those of the rich industrialized world (some conspicuous exceptions include South Korea, Singapore, and several oil-rich Gulf states). The U.S. and Australia originally signed up to Kyoto targets, but then pulled out. The protocol came into force in 2005, and at the end of that year, its signatories agreed to start negotiations on tougher cuts to come into force after 2012.

So far, so good. But the current Kyoto targets are very small compared with the cuts in emissions that will eventually be needed. And the delay has effectively shut off the option of a safety-first limit on carbon concentrations in the atmosphere. Some European countries have set themselves informal targets of a 6o percent emissions reduction by midcentury, which is closer to what is needed. But even if all the Kyoto nations did likewise, they are responsible for only a minority of emissions today. So more cuts by other nations would still be needed.

Eventually, if the climate regime develops as many hope, every coun try and every major energy and manufacturing company will need a license to emit greenhouse gases. The system, some say, could even be extended to individuals. If we are to stop dangerous climate change, the number of licenses available will have to be very limited. So the question of how they should be shared out becomes critical. It is political dynamite. The very suggestion sets the industrialized and developing worlds at loggerheads. This is partly because the industrialized countries of Europe and North America have already used up something like half of the atmospheric "space" available for emissions, and partly because developing nations are coming under pressure to reduce their emissions before they have had a chance to industrialize.

Big developing nations like China and India may have high national emissions. But measured in ratio to population, their emissions remain low. While the U.S. and Australia emit around 5.5 tons of carbon a year for every citizen, and European countries average around 3 tons, China is still around r ton, and India below half a ton. Developing countries feel they are being asked to forego economic development to help clean up a mess they did not create. On the other hand, they increasingly see that climate change threatens their prospects for economic development. The only solution is to institute a rationing system for pollution entitlements, based on a shared view of fairness.

Perhaps the simplest blueprint is "contraction and convergence." Developed by a small British group called the Global Commons Institute, it is attracting support around the world. The contraction half of the formula would establish a rolling program of annual targets for global emissions. The targets would begin roughly where we are today, and would fall over the coming decades. They would be set so as to ensure that the atmosphere never passed whatever limit on carbon dioxide concentrations the world chose.

The convergence half of the formula would share out those allowable global emissions each year according to population size. So national targets might begin at about r ton of carbon per person and then fall to maybe half a ton by 2050 and to that much less again by 2 zoo, depending on the global target chosen. Of course, at the start that would leave rich nations with too few permits and many poor nations with more than they needed. So they would trade. The costs of buying and selling pollution licenses would be a powerful incentive for a global cleanup.

Fantasy politics? Maybe. But something on this scale will be needed if we are to prevent climatic disaster. And if the rich world wants the poor world to help clean up its mess, and save us all from dangerous climate change, then some such formula will be needed.

TECHNOLOGICAL FIXES

Politics aside, what are the practicalities of stabilizing climate? President George W. Bush may have become a pariah in environmental circles for refusing to sign the Kyoto Protocol, but he is right on one thing: ultimately, it will be technologies, rather than politics, that solve the problem. The only question is what politics will best deliver the technologies that will allow us to "decarbonize" the world energy system. Those technologies fall into four categories: much more efficient use of energy; a switch to lowcarbon and carbon-free fuels; capturing and storing or recycling some of the emissions that cannot be prevented; and finding new methods of storing energy, such as hydrogen fuel cells.

The task sounds daunting. But, in truth, much of it goes with the grain of recent economic and industrial development. In the past thirty years, global carbon dioxide emissions have grown only half as fast as the global economy-thanks mostly to improved energy efficiency. And many of the new energy technologies we will need are already in use, offering benefits such as cheaper or more secure energy. The replacement of coal with lower-carbon natural gas, oil with ethanol made from biofuels, the development of wind and solar power, the proposed expansion of nuclear energy, and investment in energy efficiency all fall into this category. What is needed first is faster progress in a direction in which we are already headed.

The top priority should be energy efficiency. More than half of the immediate cheap potential for reducing carbon dioxide emissions lies in improving energy efficiency in buildings, transport, and industry. Much of it could be done at zero or even negative cost, because the cost savings would outweigh the investment. This is also the area where we as individuals can most easily make a difference-by buying energy-efficient light bulbs and appliances, insulating our homes properly, cutting down on car use, and choosing energy-efficient models such as hybrids.

Also in the short term, there is huge potential to equip the world's fossil-fuel-burning power stations with "scrubbers" to remove carbon dioxide and deliver it via pipelines for burial underground. The technology is already developed and only needs scaling up. The potential global storage capacity in old oil and gas wells alone approaches a trillion tons of carbon. The British government's chief scientist, David King, says that by 2020 Britain could be burying a quarter of its power-station carbon dioxide emissions in old oil fields beneath the North Sea.

Other technologies will take more development before they become cost-effective on a large scale. These include solar power, which is available but currently too expensive for widespread use, and turning hydrogen into the fuel of the future for transport. The idea here would be to manufacture hydrogen in vast quantities for use in batteries, known as fuel cells, to power cars. Hydrogen would become the "new oil." Hydrogen is manufactured by splitting water into hydrogen and oxygen, which is a very energy-intensive process. So if the energy for splitting water were generated by burning fossil fuel, there would be little environmental gain; but if the energy came from renewables, such as solar or wind power, that would change everything.

The hydrogen fuel cell is not so much a new source of energy as a new way of storing energy. It could be the only way to make cars truly greenhouse-friendly. And it may turn out to be the best way of utilizing fickle renewable energy sources like wind and the sun. The big problem with these energy sources is that wind cannot be guaranteed to blow (nor the sun to shine) when the energy is needed. But if the energy is converted into hydrogen, it can be kept for future use.

So what, exactly, would it take to deploy all these technologies in order to bring climate change under control? The most ambitious attempt so far to produce a simple global blueprint comes from Robert Socolow, an engineer at Princeton University. He admits that when he checked out the plethora of options for cutting greenhouse gases, he was overwhelmed, and figured that most politicians and industrialists would be, too. So he decided to break the task down into a series of technological changes that would each cut global emissions of carbon dioxide by about 2 5 billion tons over the coming fifty years. He called them "wedges," because the impact of each would grow gradually, from nothing in the first year to a billionton emissions cut in the fiftieth year. They would each cut a "wedge" out of the graph of rising carbon dioxide emissions.

Socolow proposed more than a dozen possible wedges, but said that seven would be necessary to stabilize emissions at current levels. But we need to do more than that: we need to stabilize actual concentrations of greenhouse gases in the atmosphere, and that would require reducing emissions from their current 8.2 billion tons a year to around 2.2 billion tons. So I have adapted Socolow's blueprint to allow for that tougher target. We might choose the following twelve wedges, each of which could cut emissions by about 25 billion tons over the coming half century, and reduce global emissions from the projected 15.4 billion tons a year by 2060 to 2.2 billion tons:

• universally adopt efficient lighting and electrical appliances in homes and offices;

• double the energy efficiency of 2 billion cars;

• build compact urban areas served by efficient public transport, halving future car use;

• effect a fiftyfold worldwide expansion of wind power, equivalent tc 2 million i-megawatt turbines;

• effect a fiftyfold worldwide expansion in the use of biofuels for vehicles;

• embark on a global program of insulating buildings;

• cover an area of land the size of New Jersey (Socolow's home state) with solar panels;

• quadruple current electricity production from natural gas by converting coal-fired power stations;

• capture and store carbon dioxide from i,6oo gigawatts of natural gas power plants;

• halt global deforestation and plant an area of land the size of India with new forests;

• double nuclear power capacity;

• increase tenfold the global use of low-tillage farming methods to increase soil storage of carbon.

ECONOMICS OF THE GREENHOUSE

How much might all this cost? In 2001, a team of environmental economists assembled by the IPCC reviewed estimates for stabilizing atmospheric concentrations of carbon dioxide by 2100. They ranged from a low of $200 billion to a high of $ 17 trillion-almost a hundred times as much. It seems extraordinary that estimates could range so widely. But, when these are boiled down to their basics, it appears that much of the difference depends on whether the modelers assumed that the necessary technical and social changes would "go with the flow" of future change, or that everything would have to be grafted onto a society and an economy heading fast in a different direction.

Put simply, the high estimates guessed that, under business as usual, rising wealth would produce and require almost equally fast rises in emissions from burning cheap carbon fuels. Diverting from that path would thus require preventing emissions of trillions of tons of carbon using expensive technologies that would not otherwise have been developed. The lower estimates assumed that the world was already slowly losing its addiction to carbon fuels, and that all we would need to do is make the switch faster. They also took a rather different view of technological development, seeing it as molded by a range of economic incentives. In this version, governments could shape technological development by stimulating markets. Once the process was under way, innovation would go into overdrive, and prices would fall away.

Some of the people involved in the IPCC study were instinctively hostile to major efforts to cut carbon dioxide emissions. The Yale environmental economist William Nordhaus suggests that "a vague premonition of potential disaster is insufficient grounds to plunge the world into depression." But let us assume that the real costs will be toward the top end of the range. Would their adoption really push the world into recession?

The veteran climate scientist Stephen Schneider, of Stanford University, redid the arithmetic in 2002, assuming it would cost $8 trillion to stabilize carbon dioxide concentrations by 2100. He found that the same economists who predict doomsday if we try to tackle climate change also believe that citizens of the world will be, on average, five times richer in a hundred years than they are today. So he took the economists at their word and asked: How much would the $8 trillion bill for halting climate change delay those riches? The answer was just two years.

"The wild rhetoric about enslaving the poor and bankrupting the economy to do climate policy is fallacious, even if one accepts the conventional economic models," he told me when his analysis was published. Coincidentally, that was the week that Australia's prime minister, John Howard, announced that his country would not ratify the Kyoto Protocol because it would "cost jobs and damage our industry." Poppycock, said Schneider. "To be five times richer in 2100 versus 2 102 would hardly be noticed." It was a small price to pay.