Believe me, Master Doctor, this makes me wonder above
the rest, that being in the dead time of winter and in the
month of January how you should come by these grapes.
Reviewing the last nine chapters, I discover that I have been uncharacteristically kind to business. I have concentrated on the measures which might reduce the amount of carbon we emit directly, rather than that released on our behalf by industry. So I will attempt to salvage my reputation by examining two enterprises: retailing and the manufacture of cement. I have chosen them because their carbon emissions, which are very great, are, at first sight, particularly hard to address.
The business practices of the superstores sometimes look like a carefully designed project to destroy the biosphere as swiftly as possible. Their freight transport arrangements, for example, seem almost perversely designed to maximize the distance travelled. Among the examples I came across when researching another book (Captive State) was that of the vegetables being sold in two superstores on the outskirts of Evesham in Worcestershire, in central England. They had been grown just two kilometres from the town. First they were trucked to Herefordshire, some 70 kilometres away, then another 130 kilometres or so to a pack-house in Dyfed in south Wales, then a further 290 kilometres to a distribution depot in Manchester, then 180 kilometres back to Evesham.2
Like Dr Faustus, who brought grapes from the southern hemisphere ‘by means of a swift spirit that I have’ to feed a pregnant duchess, the supermarkets respond to – and help to create – a demand for unseasonal produce. Before air freight was cheap, no one but Queen Victoria thought of demanding perishable food from the other side of the world. She is alleged to have offered a large reward to anyone who could bring her a fresh mangosteen. Lacking Faust’s powers, no one was able to claim it. Today it is often harder to find a British apple in the shops than a mango or a papaya. Herrings, in the United Kingdom’s superstores, are rarer than tiger prawns. But the shops take advantage not only of the other hemisphere’s contrary summer, but also of its lower labour costs, cheaper land and economies of scale. We are all now familiar with out-of-season Coxes from New Zealand on our shelves – which taste like Kleenex soaked in Diet Coke – when our own apples, perfectly ripe, are falling from the trees through lack of buyers. We have all now seen the potatoes and onions marked ‘South Africa’ or ‘Chile’ or ‘Australia’, and the bottled water, effectively indistinguishable from that which comes from our taps, imported from the other side of Europe.
But this is not another section on transport. With the introduction of carbon rationing, unnecessary freight of this kind will simply be priced off the shelves. I know that some people will find this hard to swallow. In her book How to Eat, the celebrity chef Nigella Lawson dismisses concerns about long-distance transport thus:
If you live in the Tuscan hills, you may find different lovely things to eat every month of the year, but for us it would mean having to subsist half the time on a diet of tubers and cabbage, so why shouldn’t we be grateful that we live in the age of jet transport and extensive culinary imports? More smug guff is spoken on this subject than almost anything else.3
Lawson’s requirement for asparagus in October plainly takes precedence over other people’s requirement for survival. But she also betrays a limited imagination. Rocket, lamb’s lettuce, purslane, winter cos, land cress, kale, leeks, chicory, pak choi, choi sum, mizuna, komatsuna, mooli, winter savory, coriander, parsley, chervil, spring onions, spinach, sorrel and chard will grow through the winter in the United Kingdom. Some need cold frames or cloches to protect them from the lowest temperatures, but none requires a heated greenhouse. Carrots, parsnips, potatoes of all kinds, beetroot, onions, garlic, swedes, pumpkins, squashes, celeriac, salsify and scorzonera can be stored without refrigeration. Scores of old apple varieties, among them some of the best ever cultivated – Ashmead’s Kernel, Ribston Pippin, Aromatic Russet, Belle de Boskoop, Pitmaston Pineapple, Allen’s Everlasting, Court Pendu Plat, D’Arcy Spice – have been developed to last through the winter in an insulated shed. Even in Marlowe’s day, horticulture was sufficiently advanced to produce an apple – the Winter Greening or Apple John – which would still be edible, if wrinkled, two years after it was picked.4 In Henry IV Part I, Falstaff complains that
my skin hangs about me like an old lady’s loose gown; I am withered like an old apple-john.5
And this is to say nothing of the products (some, like damson jam and raspberry vinegar, quite exquisite) of smoking, salting, drying, pickling and preserving. If Nigella Lawson can’t summon the wit to make a decent meal from ingredients like this, she should find herself another job. In short, given that much of the food brought here from afar is picked so early that it rots before it ripens, it is not hard to see how our diet, even for those of the most refined and demanding tastes, could in fact be improved by means of geographical restriction.
But even if we were (because the solution to this profligate use of fuel is so obvious) to disregard the means by which our retailers obtain and distribute their goods, their consumption of energy remains astounding. The table below gives the figures for shops and other buildings. Given that nothing except money is made in most
sector |
space heating and domestic hot water (kWh per m2) |
electricity (kWh per m2) |
warehouses |
64 |
81 |
local government offices |
95 |
39 |
commercial offices |
147 |
95 |
factories |
245 |
47 |
retail |
185 |
275 |
Source: Royal Commission on Environmental Pollution.6
shops, the fact that their heat demand is not far behind that of factories, while their requirement for electricity is almost six times as great is, at first, scarcely credible. But then you think your way around. As you come through the door of a supermarket, a unit above your head blasts you with hot air in the winter and cold air in summer (sometimes, when the manager has not been paying attention, it is the other way around). You must stand blinking for a moment as your eyes adjust to the lights. Then you walk past banks of fridges and freezers which have no doors. This would be impossible to believe, if it were not by now one of the most ordinary facts of life. But, though you walk through valleys of ice, you remain warm. All day long, the freezers and the heaters must fight each other. They must do so in a building which is huge, generally uninsulated and often widely glazed: that is capable, in other words, of trapping neither heat nor cold.
In the hope of finding the means by which the superstores might achieve major cuts in energy consumption, I visited a senior manager from one of the big chains. I cannot name him or his company, but its practices appear to be no worse than those of its competitors. He began by giving me an idea of where the energy goes.
The heaters over the doors each have a rating of 50 kilowatts. This is roughly seventeen times as powerful as a standard domestic fan heater. The aisles are lit to an intensity of 1,000 lux, which is about the same saturation as a TV studio, and two or three times that of an office. The counters are brightened with spotlights – at up to 2,000 lux. Fish, in particular, must sparkle, so they are lit with ceramic discharge metal halide lamps, which are otherwise used to illuminate castles and cathedrals at night. You begin to understand what this means when you remember that fish have to be kept on ice, while lamps of this brightness could fry them. But, my contact told me, ‘If you light it, it will sell. You can’t afford not to do it.’ Between 20 and 25 per cent of his chain’s energy budget, he told me, is spent on lighting.
Most of the rest – 64 per cent – is used for refrigeration. Every open freezer costs his firm £15,000 a year. When the company fitted glass doors to the top half of its cabinets (the vertical portion, at eye level), it cut its refrigeration budget by around one quarter. It could do the same again if it fitted doors to the chest freezers underneath, ‘But the traders [the managers of the stores] won’t have it.’ When customers open a freezer door then close it, it can steam up, obscuring the view.
We then discussed what his company might be able to do to reduce its energy demand. He appeared to have looked into almost every possibility, and the answer, he had found, was not very much. The ceramic discharge spotlights the chain is now using to light its counters are three times as efficient as halogen lamps, and in a few years’ time it might be possible to replace them with light-emitting diodes, which are three times better still. At present, however, LEDs ‘just don’t deliver the punch we want’, and the demand for lighting rises inexorably. Similarly, though the company has started replacing its older models,
We can’t reduce the overall refrigeration budget, as the number of fridges is growing faster than our efficiency measures.
If the managers took greater care in turning off appliances when they are not needed, they might be able to cut the energy budget by 5 per cent. Ventilating a store at night would reduce the amount of air conditioning it needs when the customers arrive, but natural ventilation, he said, is unpopular with the traders, as it is hard to guarantee consistent temperatures. It might be possible, in new stores, to pump some of the excess heat into the ground during the summer, and tap it in the winter. I suggested that his chain could gather heat from pipes laid under its car parks, but he was unenthusiastic.
Instinctively, I would say it’s a no-goer. During construction, there are trucks and bulldozers running all over the site.
They would smash the pipes before the tarmac was laid. He had looked into ‘sunpipes’: tubes which bounce natural light into the store.
They are promising, but quite expensive, and they don’t reduce our capital costs, as we still need full lighting when it gets dark.
Local wind power, he said, is useless: ‘on a cold, still day, you’re stuck.’ Solar panels are far too expensive and – in the buildings he had visited – produced much less electricity than the installers claimed.
Combined heat and power currently costs more than his bosses are prepared to pay.
All that counts is cost… Everyone has to move, or no one moves. If we do it and nobody else does, we’re lost. Who is going to be the first to do it?… Retail is a very harsh environment.
One chain – J. Sainsbury – claims it has been the first to blink. In 1999 it opened ‘the UK’s most environmentally responsible supermarket’ on the Greenwich peninsula in London.7 It uses an earth cooling system for air conditioning, natural light from north-facing windows, a gas-fired combined heat and power station, solar panels and two wind turbines. These innovations, the company claimed, were ‘expected to reduce energy consumption by up to as much as 50 per cent compared to a standard store of a similar size and operation’.8
Savings of this magnitude, if replicated everywhere and combined with measures to reduce the carbon content of our electricity and heat that I discussed in Chapters 5 to 7, could deliver a total cut of 90 per cent, assuming that the supermarkets’ energy use does not continue to rise. But are they real? My researcher contacted J. Sainsbury three times, hoping to obtain the operational figures, and to discover whether or not they had been independently audited.9 Six months later, we are still waiting for a response. Until it comes, jaded by the false claims of other companies, I reserve the right not to believe a word it says. Indeed, the only firm figures I can find for this ‘watershed in supermarket architecture’10 give me further cause for suspicion. The store’s two wind turbines, which Sainsbury’s customers see when they enter the car park, are each 3.6 metres in diameter.11 This suggests, at mean windspeeds of 4 metres per second, that their average combined output is a little over 0.4 kilowatt hours* – a microscopic fraction of the power the store must use. Even this is likely to be generous, as they stand just 12 metres from the ground, and their poles support advertising hoardings, which must create turbulence.
I have already uttered the dread words ‘car park’, which hint at the third and perhaps least tractable impact of the superstores. Car journeys account for 62 per cent of the visits made to shops,13 and for almost all the trips to shops outside the town centres. The Department for Transport’s figures suggest that shopping accounts for 20 per cent of the journeys made by the United Kingdom’s drivers, and 12 per cent of the distance covered.14
It is not easy to see how people visiting out-of-town shops could be persuaded to travel by other means: carrying a week’s worth of groceries on the bus or by bicycle offers little by way of entertainment. To judge by the size of the car parks they keep building, and their efforts – so far successful – to prevent the government from imposing parking fees on their customers,15,16 the superstores have no intention of encouraging people to change their habits. Their customers show no inclination to be encouraged. In this respect at least, shops appear to be locked into profligate levels of energy use.
In other words, if the existing infrastructure and existing shopping patterns are to persist, the scope for cutting emissions is limited. But it seems to me that there might be a means of reconciling a 90 per cent carbon cut with quick and easy shopping. My proposal could solve both the transport problem and the refrigeration and lighting problem in one stroke. It’s hardly new: it is a revolutionary idea called delivery.
According to the Department for Transport,
a number of modelling exercises and other surveys suggest that the substitution of private cars by delivery vehicles could reduce traffic by 70 per cent or more.17
Every van the superstores dispatch, in other words, appears to take three cars off the road. Already the supermarkets (as well as plenty of new companies) are, with the help of television and the internet, reverting to a way of doing business they abandoned decades ago. At least a couple of times a week, I see a Tesco delivery van coming down my street. I suspect that I am fated to be appropriately run over one day by an organic vegetable box van, as so many of them now infest my home town. The Office of National Statistics calculates that deliveries comprise about 4 per cent of total retail sales; the transport department’s paper suggests this might be an underestimate.18 Sales of goods on the internet appear to be growing almost exponentially, though for obvious reasons there are no reliable figures.
None of this, by itself, will save us. Most shopping will continue, under the existing system, to be done by car, and the stores will continue to freeze their goods and heat their customers in the open air. But if deliveries were to replace shopping in distant stores in its entirety, we might have a formula for an 80 or 90 per cent reduction in carbon emissions, even before we consider the use of renewable power and carbon capture and storage.
My proposal amounts to this: that the out-of-town stores are gradually replaced with warehouses. No one visits them but suppliers and the company’s staff. They require no supersaturated lighting, no open freezers, no heaters above the door.
Warehouses, as you can see from the table printed a few pages ago, use – per square metre – about 35 per cent as much heat and 29 per cent as much electricity as shops. But you can pack many more goods on to a square metre of warehouse than you can on to a square metre of superstore. There is no need for displays, broad aisles or cash tills, and the shelves can be built much higher. My supermarket contact told me that the stockrooms attached to his stores – through which all their goods must pass, if only fleetingly – are probably responsible for around 5 per cent of the chain’s total energy bill.
If, in other words, instead of picking goods from the shelves of their shops – as the superstores do now – then loading them into vans, they were to deliver them straight from the warehouse, not only would they cut the transport emissions caused by collection by 70 per cent, but they could also reduce their static energy consumption* by some 95 per cent. Major shopping trips would, in other words, be eliminated. Local shops (which are much less dependent on cars) could remain open, but they would have to start introducing the kind of efficiency measures which apply to the rest of the economy.
It seems to me that there may be a further environmental advantage to this proposal: that fancy packaging would no longer be considered necessary. As the point of sale is the computer or the television or the telephone, and the visual stimulus is the catalogue (either electronic or printed), the goods can be delivered in plain parcels, using no more paper or plastic than is required to keep them clean and fresh. This, for example, is how I buy my vegetable seeds. The companies I use publish online catalogues full of beautiful pictures of healthy plants (which look nothing like the slug-reamed specimens I grow) then send me the seeds in brown paper envelopes. This presentation does nothingto diminish either the excitement I feel when they arrive or the eventual disappointment.
At first glance, the business case for a complete transition to virtual shopping seems as sound as the environmental case. Capital, staff and overheads costs are all reduced. But it is naïve to imagine that this model would recommend itself to the existing stores. Their profitability depends in part upon the scarcity of sites for which planning permission can be obtained. In many places, the local market has been monopolized by a single company. Because costs are lower and available sites more numerous, the warehouse model allows far more companies to play, as the explosive growth of small organic box schemes shows.
But whether they like it or not, the superstores have already demonstrated that it can be done. Their deliveries are more reliable than those of other companies. While many firms keep you waiting indoors all day, the market leader in internet shopping– Tesco – promises to deliver within a two-hour period.19 In most parts of the country, you can choose to receive your groceries at any time between 9 in the morning and 11 at night during weekdays, and during most daylight hours over the weekend.20 In other words, whatever the firms might think of it, this kind of shopping is likely to be more convenient for their customers than the existing model – which is why the sector seems to be growing so quickly. If my proposal were adopted, it could also be a good deal cheaper. Some people object that deliveries which depend on telecommunications exclude those without the technology; but far fewer households are without televisions or telephones than without cars: my proposal is, in other words, more inclusive than the current system.
But the closure of the out-of-town stores, for the reason I have given, is unlikely to happen by itself. It would need to be stimulated either indirectly – by our rationing scheme – or directly, by regulation. In either case, however, it seems to me that this switch involves no significant reduction in human freedom, unless the right to travel round the ring road to an overlit glass box and stand in a queue is to be represented as an unalienable component of life, liberty and the pursuit of happiness.
I have learnt from bitter experience that it is not easy to interest people in cement. But it interests me, partly because its carbon emissions are not confined to those produced by burning fossil fuel. Making ‘Ordinary Portland Cement’, which is the grey stuff known to almost everyone as plain ‘cement’,* is a matter of turning limestone (calcium carbonate) into calcium oxide. This means producing carbon dioxide.†
The chemical process – ‘calcination’ – releases around 500 kilograms of the gas for every metric tonne of cement it makes.22 The raw materials must also be ground and then heated to about 1450°. Altogether, according to a study published in the Annual Review of Energy and Environment, the manufacture of 1000 kilograms of cement emits, on average, 814 kilograms of carbon dioxide.†23 This does not take into account the energy costs of quarrying and transport. It is probably fair to say that a tonne of cement produces about a tonne of carbon dioxide.
According to David Ireland of the Empty Homes Agency, writing in the Guardian, a house requires, on average, 25 tonnes of concrete for the foundations and floors, and 4 tonnes for mortar and rendering. One tonne, he says, is wasted.24 He suggests that this results in the release of 30 tonnes of carbon dioxide. But he appears to have confused concrete with cement. The concrete for foundations and floors contains roughly one part of cement to five of sand and gravel. Even so, this suggests, if his other figures are correct, that every new home requires about 5 tonnes of cement, which emits 5 tonnes of carbon dioxide. Even if we were to forget about all the other materials from which a house is built, this equates to four times a single person’s annual carbon ration in 2030.
Altogether, depending on whose figures you believe, cement produces between 5 and 10 per cent of the world’s manmade carbon dioxide.25,26,27 In the United Kingdom, where we are replacing our houses very slowly, it accounts for just under 2 per cent.28 Partly because of the construction booms in South and East Asia, global cement production is growing by about 5 per cent a year.29
It appears to be as easy to capture the carbon dioxide produced by both the calcination process and the combustion of the fuel which fires the kilns as it is to capture the gas from power station exhausts.30 Burying it, however, is another matter. Unlike power stations, cement works are geologically constrained: they must be built beside a source of suitable limestone. Though all are to be found in sedimentary basins, there is no evident relationship between limestone outcrops and the salt aquifers and gas and oil fields in which carbon dioxide might be buried. Although most cement plants in the United Kingdom probably lie within 500 kilometres of a suitable aquifer (which is roughly the distance over which the gas can be pumped economically31), until maps of appropriate burial sites are published, I can’t tell whether or not the technology could be universally applied. But I can state with confidence that the United Kingdom – which is the most geologically diverse region of its size on earth – is atypical. In larger countries, where the geology is less varied, there must be cement plants whose emissions cannot be stored below ground.
Only part of the problem can be solved by building less. There are plenty of uses of concrete – such as new motorways and runways – which are unnecessary and unsustainable. The environmental cost of cement manufacture provides a further powerful argument to stop expanding the transport networks. But, as I mentioned in Chapter 4, many of the homes in the United Kingdom are simply incapable of keeping heat in and weather out. If it can be demonstrated that there are major and rapid carbon savings to be made by knocking them down and rebuilding them, the rate of demolition should increase. The passive houses with which I would like to replace them use more materials than ordinary homes of the same size, as they require a high ‘thermal mass’. Even if this were not the case, they couldn’t be built entirely from the remains of the old homes: concrete can be recycled, but not as cement – it is used as ‘aggregate’, or crushed stone.* We’ll also need plenty of concrete in which to set our wind turbines.
So the next obvious step is to find means of making the cement we use go further. At first sight, something called AirCrete (or ‘autoclaved aerated concrete’) seems to provide the answer.33 When cement is mixed with quicklime, sand, water and aluminium powder, it rises in the mould like a loaf of bread. AirCrete blocks are strong and they keep the heat in. Because between 60 and 85 per cent of their volume is air,34 they contain much less cement than solid blocks. Unfortunately, the carbon savings appear to be thrown into reverse by the aluminium powder.35 This is the component that acts as the yeast in the concrete dough, generating the bubbles which make it rise. Though much smaller quantities are used, the energy costs of smelting aluminium are around forty times as great as the energy costs of manufacturing cement.36
A more promising approach is the replacement of ordinary mixtures with High Strength Concrete, which contains additives such as silica fume† and finely ground fly ash. Because it is extremely strong,‡ it allows builders to halve the weight of the materials they use.38 The additives are quite expensive, but because the volume of materials and the transport costs are smaller, the overall cost is generally lower.39
The problem is that the industries which produce silica fume are moving out of the rich nations, which means that the carbon costs of transport will rise, while fly ash is, on the whole, the product of burning coal in power stations, which I am seeking to prevent. A similar problem affects another proposal for reducing the carbon content of cement: mixing it with slag from blast furnaces. Not only are steel-makers closing down in many of the rich nations, but those which remain are switching to newer steel-making technologies (such as the electric arc furnace), whose slags don’t have the right properties.40
In 1997, a proposal by a materials technologist from Nevada called Roger Jones caused great excitement in those parts of the media (which I admit are not numerous) that follow developments in the cement industry.41,42 He suggested turning cement back into limestone, by forcing it to reabsorb the carbon dioxide it loses during the calcination process.
This happens anyway, if very slowly. According to New Scientist, ‘a large slab of concrete could take 30,000 years to carbonate fully.’43 This is a little beyond the timescale considered by this book, though at current demolition rates in the United Kingdom, we can expect some of our houses to turn to limestone before they are pulled down. Jones discovered that supercritical carbon dioxide (heated and compressed to just over 1,000 pounds per square inch44) can pass straight through concrete, carbonating it in minutes and doubling its strength.45 The cement would reabsorb all the carbon dioxide it lost during calcination. The supercritical gas could, Jones claimed, simply be sprayed on.46 Instead of being buried, carbon dioxide captured in cement works could be poured back into the cement.
In April 2006, I phoned Roger Jones in Nevada to find out what had become of his proposal. ‘It really wasn’t for concrete, George,’ he told me. ‘It was for plastics. It’s a very expensive process, so we never intended that it should go in that direction.’47
This surprised me, not least because a press release still to be found on his company’s website claims that his process
transforms common portland or lime cemented materials and clays by treatment with carbon dioxide… ‘Like living coral, now we can take carbon dioxide out of the environment and build our houses with it.’48
This, in other words, is a further demonstration of the need to be wary about the speculative claims made by people with a commercial interest. The same consideration makes me cautious about the plans announced by a company called TecEco to produce cement made from magnesium – rather than calcium – oxide, even though in some respects it sounds quite promising.
Magnesium carbonate needs be heated to only 650° to make cement,49 which greatly reduces the energy costs of manufacturing it. The oxide also seems to absorb carbon much faster than calcium cements do: the man who runs the company claims it takes just a few months and that it ends up stronger than ordinary cement.50 The problem is that magnesium carbonate is rarer than limestone. This means that it is more expensive and – unless the cement is sold only in the regions which produce it – incurs greater transport costs. But it might be useful in some places.
There does, however, seem to be a solution, and once more it is, in concept, a very old one. It is a material similar to the pozzolan cements with which the Romans built the domed roof of the Pantheon and hundreds of other structures, some of which are still standing today.51 The institute which promotes it claims that it sets so quickly and to so great a strength that ‘a heavy Boeing or Airbus can land on a runway’ patched with this material only four hours after the repair took place.52
While this is not the example I would have chosen, it does testify to properties that no paper I have been able to find disputes. This material sets quickly, appears to be stronger than ordinary cement, lasts longer, shrinks less and is more resistant to fire.53 ‘Geopolymeric cements’, as these materials are known, can be manufactured from several kinds of clay and industrial waste and quite a few common sedimentary rocks.* They are cheap and, most importantly, their fabrication produces between 80 and 90 per cent less carbon dioxide than Portland cement.54,55 This is because they are formed at lower temperatures (about 750°) and the chemical process doesn’t depend on releasing carbon dioxide. According to the Australian government’s research body, CSIRO, they can be used for every major purpose for which ordinary cement is bought today.56 The reason why they are not yet widely manufactured is that artificial geopolymers – which don’t depend on the rare deposits of natural pozzolana (a type of volcanic ash found around the Bay of Naples) used by the Romans – were invented only in the late 1970s.57 The construction industry is notoriously conservative, and the cement companies have a powerful financial incentive to maintain their existing plants, rather than to start up somewhere else with a different process.
But the answer, or most of it at any rate, appears to exist. By 2030 there should be no plants in the rich nations which are not either burying their carbon or producing geopolymers instead of Portland cement. And if extra materials are needed for building better houses, that growth should be offset, perhaps even reversed, by halting the construction of new roads and runways.
Re-reading this section, I am forced to admit that cement is in fact a rather dull subject. I beg your forbearance on the grounds that to address only those sources of carbon dioxide which are interesting would be to succumb to another kind of aesthetic fallacy.
So I think I might have got there, more or less. I hope I have been able to show that we could cut our carbon emissions by around 90 per cent in all but one of the sectors I have investigated: in the home, on the roads, and in two industries which at first sight seemed particularly difficult to reform. The sector in which I have failed – and I hope I am not letting myself off too lightly here – happens to be the one which is least necessary to our survival. Unlike heating, lighting, travelling to work, building or shopping, aviation is not required to sustain civilization, though its loss from the lives of most of the people who use it today will be keenly felt.
I can’t pretend that my proposals are anything other than extremely challenging. They can be implemented only if tackling climate change becomes the primary political effort not just in our own country but in all rich nations. They require a good deal of money and a great deal of political will and expertise to enact. But what I hope I have demonstrated is that it is possible to save the biosphere. If it is possible, it is hard to think of a reason why it should not be attempted. It is true that this effort will disrupt our lives. But it will cause less disruption than the alternative, which is to allow manmade global warming to proceed unhindered.