The future of cities: hazards and environmental change
At present we are preoccupied with the global crisis over money and credit, with prospects of a major recession. We are also preoccupied with a combination of environmental problems, high among them climate change, or as I prefer to call it climate destabilization. Both crises affect the future of cities and their role in our society.
Underlying our prospects for the future is our failure to come to terms with the impacts which our animal species is having on the surface of the Earth and all life within it. Most things have happened in the long history of the Earth, but our current circumstances are unique. To make sense of the scale and character of the impacts, we have to reckon with such issues as human population increase, degradation of soils, exploitation of resources, pollution of water both salt and fresh, climate change, and destruction of the other living species both large and small on which we wholly depend.
So far the most conspicuous demonstration of the human impact has been the growth of cities. Seen from space, they look like rapidly growing pimples on the surface of the Earth, a sort of global measles, testifying to favourable conditions and proliferation of the organisms that produce them. At night they become points of light, occasionally animated by flares that come from the extraction of the fossil fuels that make them possible in their current form.
In 1900 some 15 percent of the world's 1.5 billion people lived in cities. By 2000 city-dwellers accounted for more than 47 percent of a world population of more than 6 billion, and in 2010 that proportion already exceeds 50 percent. By 2050 some 70 percent are expected to do so, mostly in poor countries. What has happened?
The urban phenomenon goes back to that brief patch of time which followed the end of the last spasm of the ice ages some 11,000 years ago. Hunter-gatherers began to settle in fixed communities; deforestation and farming followed; communities became villages, and villages became towns; society became more hierarchical with division of functions; and the first cities arose in different parts of the world and different geographical circumstances. From the beginning such cities were immensely vulnerable to change, whether from changes from within or without. The story of why some cities collapsed, recovered, collapsed and recovered again is a
critical element in human history. Many attempts had been made to produce a coherent explanation, notably by Joseph Tainter in his book The Collapse of Complex Societies (first published in 1988), and later by Jared Diamond in Collapse.
The history of Mexico, or rather of Mesoamerica as a whole, well illustrates this broad theme. We can distinguish the remains of cities built by the Olmecs some 2,500 years ago. This provided the base for the cities and cultures built between 800 and 1,000 years later by the Maya, the Zapotecs, the Teotihuacanos. Then came the cities of the Toltecs, the Aztecs and others up to the arrival of the Spaniards in the 16th century. Some of these remains are clearer than others. They range from the magnificent pyramids of Copan, Chichen Itza, Monte Alban and Teotihuacan to the now forested areas of Yucatan and Belize. Only from the vantage point of a helicopter could I detect the traces of an abandoned city around Caracol in Belize.
The circumstances in which these cities collapsed remain a matter of energetic debate. The reasons were complex and different in different circumstances. In many cases they could have outgrown their resource base, whether in the form of water or food supplies; the climate could have changed; there was certainly warfare between cities and internal social conflict as things went wrong and their economic health deteriorated. Even if the process began again as circumstances improved, cities remained - and remain - vulnerable. Our situation is not too different today.
More recently those of us who live in industrial countries have to recognize that the last 250 years have been a bonanza of inventiveness, exploitation and consumption which is unlikely to continue. It is based on cheap energy and rapid exploitation of apparently endless resources. During that time humans have moved more rocks and soil, and poisoned more topsoil and water than all their predecessors ever did, and certainly more than all natural change, whether from volcanoes, changing climate or even tectonic plate movement ever brought about. The process, usually labelled 'development', has spread or is spreading to most parts of the world.
Looking back, cities have so far had three broad characteristics, all evident in the history of Mexico. One has been called sacredness of place, or a relationship with divine forces through pyramids, temples, cathedrals or mosques. The second is as a place of refuge from lawlessness: in other words simple self protection. The third is as a focus for commerce, industry, innovation and the generation of wealth.
Today perhaps the third characteristic is most important. But even there change is under way. Whatever the continuing attraction of cities in some parts of the world, their attraction is diminishing elsewhere. Perhaps something of the sacred element remains, but with the growth of shanty towns and sprawling suburbs, notably in the city of Mexico, now the largest in the world, security has become worse rather than better; and with the development of information technology, commerce, business and industry have sometimes moved out. In short the very reasons for cities are under challenge.
It is not easy to put all this together. Cities are, and have always been, creatures of their environment. It was Leonardo da Vinci who first compared them to living organisms. Like such organisims, they absorb food, water and materials, and they emit waste of all kinds. The bigger and more complex they become, the more vulnerable they are to bad management from within or environmental change from without.
As humans we often reckon ourselves as the most successful species ever known in the history of the Earth. But all successful species, whether bivalves, beetles, swallows, or humans, multiply until they come up against natural stops, reach some accommodation with nature, and willy nilly restore some balance. That is what we now have to do.
The future of cities underlies much of the current arguments about climate change. The relative failure of the climate change negotiations at Copenhagen last December was caused as much by the sheer complexity of the issues governments faced and their apparently divergent national interests as by the global problems caused by human-driven climate change.
I was a member of an Urban Task Force set up by the British government and chaired by Lord Rogers of Riverside in 1999, in which we examined the problems then facing cities in Britain, and made a variety of recommendations for the future. We then returned to the problems on our own initiative six years later, underlining the need for a new approach to cities in the light of the changes taking place in society as a whole.
In broad terms we believed that our aim should be to restore communities in and out of city centres by rebuilding on old sites, protecting and enlarging green space, limiting specialization of activity (thereby avoiding dormitory versus business ghettoes), insisting on improved design, integrated planning, better public transport, the recycling of waste, the reduction of pollution, and generally taking much stronger account of social and economic as well as environmental considerations.
I cannot pretend that our answers were in any way complete. Others have taken up the same themes, and attempted in different ways to point the way ahead. All concerned with the future and the welfare of cities should ask themselves a wide range of questions, as we then tried to do. Here is a selection of them. All relate directly or indirectly to Mexico.
- Have we worked out the effects of continuing human population increase, and the need for restraint?
- Are our cities manageable in terms of such increase, and migration into them from the countryside and elsewhere in central America?
- Have we reckoned with the effects of climate change, for example more droughts in north west Mexico, and more storms and floods in the south east?
- Are there long term policies for supplying water to the big Mexican conurbations?
- What could be the effects of any change in supply on reservoirs, storage capacity and sewage systems? Are they in the right place? Can supply match increasing demand?
- Are there long term policies for reducing Mexican dependence on locally produced fossil fuels?
- How should carbon emissions from cities be restricted (at present the energy consumed by buildings worldwide accounts for 45 percent of total greenhouse gas emissions)?
- How can we move more quickly to renewable sources (wind, tide, geothermal, solar, biofuels etc), and possibly new nuclear technology (including pebble bed)?
- How should we move from macro to micro energy systems?
- How should we best promote energy saving in buildings and greater efficiency generally?
- What new technologies should be applied to transport (cars, ships, aircraft, trains etc)?
- Agriculture, food and raw materials
- How can Mexico do more to feed itself as in the recent past?
- How can we ensure the supply of food to cities? Is the current tendency towards industrial agriculture appropriate, or should we revert to more locally derived foods? Even if we do not go for self sufficiency, should we do more to ensure more self reliance?
- Should market forces continue to be seen as dominant in this part of the economy, or should governments accept more responsibility in the form of regulation? Is the ejido system in Mexico dead?
- Are other essential commodities and raw materials going to be in short supply?
- What should governments do to cope with the effects of sea level rise on cities, for example Tampico, Vera Cruz, Tehuantepec and La Paz now at increasing risk?
- What should be the priorities, and at whose expense?
- Town planning
- Will more controls on urbanization be necessary?
- How should town planning - such as it is - be adapted to take better account of the dangers of urban breakdown, the future design of buildings, new configurations of business and industry and disposal of waste?
- Can we predict changes among the micro-organisms on which we all depend? Cities are particularly vulnerable to epidemics of all kinds.
- What new as well as old diseases are likely in the changing circumstances?
- Are cities properly governed? Have we the right relationship between national, regional and urban authorities?
- Do authorities of whatever kind and howeverchosen feel accountable to local communities?
- Are governments providing the right guidance, for example through incentives and disincentives?
In coping with this intimidating range of issues, we should not despair. Over the last few years both the complexity and interconnectedness of the problems have been better understood. Model cities have been sketched out and one or two have even been built: for example the town of Curitiba in Brazil, since imitated in one or two places in the United States.
Then there is the Chinese project for Dongtan near Shanghai. Some local authorities in Britain have also attempted to see the problems on a holistic basis: for example in Woking and to some extent in London. The British government has been saying some of the right things and has even put forward the idea of eco-towns, following a useful precedent set by The Prince of Wales, but we have yet to see whether they can be made to work.
Underlying the whole issue, our most fundamental difficulty is for the need for us to think differently, and in particular to look at current economics and the way in which we measure wealth, welfare and the human condition. We need to establish true costs, including externalities, in terms of the Earth's good health. Here the Chinese may be in advance of others in defining the principles of what they call 'clean green growth' and in working out new economic methodologies. Recently we have had a report on the subject from the Stiglitz Commission and a paper by Sir Partha Dasgupta, just submitted to the Royal Society.
The trouble is that most of us, including governments almost everywhere, still do not know where our society is going. The dominant paradigm remains the consumer society which should perhaps be renamed the consumptive society. Should our prime aim be to mitigate likely change or to adapt to it? The answer is, I suppose, that it should be both for the sake of future generations.
Should there be a more coherent action plan for cities, a kind of universal standard, that we have so far not seen? Do subsidies for such city activities as transport, as in the city of Mexico, make sense? Do we have to build grossly inefficient tall glass monsters in our cities? Who is going to bang heads together in time to avoid such catastrophes as building on flood plains or in areas likely to be drowned by sea level rise? How can the public as well as governments be persuaded?
We all suffer from the disease of what has been called conceptual sclerosis. Little is more difficult than learning to think differently, above all when problems go to the roots of the conventional wisdom. Old ideas haunt us like ghosts.
It is time now to turn to the future of our species in a world which is changing before our eyes. Bear in mind that nearly all forecasting turns out to be wrong. We do well to expect the unexpected.
In his book The Meaning of the 21st Century, James Martin laid out what he saw as the prospects:
"The 21st century is like a deep river canyon with a narrow bottleneck at its centre. Think of humanity as river rafters heading downstream. As we head into the canyon, we'll have to cope with the rate of change that becomes much more intense - a white water raft trip down an unknown river with the currents becoming much faster and rougher - a time when technology will accelerate at a phenomenal rate."
He then went on to identify the main challenges facing us. In the short term all this would affect human migration between countries and continents, thereby widening divisions between the rich and poor within and between countries, increasing the vulnerability of cities, promoting the growth of terrorism, increasing the risks of war with unimaginably horrible weapons, and exhausting often irreplaceable resources. On this reckoning we would be lucky to come out on the other side of the deep river canyon with anything like civilization as we know it.
But this is not the whole story. Nor does it cover changes in the balance of economic and political power between East and West and North and South. For today let us leave that aside. Instead I want to jump a hundred years, and from this vantage look backwards. In doing so, I shall assume (I hope correctly) that humans will have faced up to and coped with at least some of these problems. People are not stupid. So what will the world look like in Mexico as elsewhere? The Aztecs always saw themselves as the People of the Sun, and looked forward to the era of the Sixth Sun. Perhaps this will be it.
First people are likely to be living in a more globalized world of rapid communication. Ideas and units of information - or memes - will pass almost instantaneously between countries, communities and individuals. The wiring of the planet with fibre optics, cellular wireless, satellites and digital television is already transforming human relationships. For the first time there will be something like a single human civilization.
Human numbers in cities or elsewhere will almost certainly be reduced, but some people will live longer, bringing its own train of problems. Their distribution will be different. It has been suggested that an optimum population for the Earth in terms of its resources would be nearer to 2.5 billion rather than - as now - almost 7 billion, or even 9 billion later this century.
Cities will be very different as communities become more dispersed. The daily tides of people going in and out of them for work will be much reduced. Energy and transport systems will be decentralized. Archaeologists of the future may even wonder what all those roads were for. There will certainly be a horrid mess for our successors to clear up.
Then there are other developments in information technology. They raise the question of evolution itself. At present we can alter isolated genes while disregarding the totality of what genes can do. As brought out in the current debates on nano-technology, we often do not know what the results of our action may be. Already chips have been inserted into humans for a variety of purposes. We can even insert extra chromosomes in the knowledge that they will not be heritable. The techniques of evolvability will themselves evolve. No wonder that Lord Rees, the current President of the Royal Society, has given our civilization only a 50 percent chance of surviving this century.
On the one hand humans may thereby be liberated from many current drudgeries. Soon houses may be able to clean themselves, robots may produce meals on demand, cars may drive under remove instruction, and the evolution of desirable characteristics might even be automated. All this seems unimaginable when so many still have to trudge miles to collect food, fuel, and water.
On the other hand humans could become dangerously vulnerable to technological breakdown and thereby lose an essential measure of self sufficiency. Already dependence on computers to run our complex systems, and reliance on electronic information transfer, are having alarming effects. Here industrial countries are far more vulnerable than others. Just look at the effects of single and temporary power cuts or, as now, severe winter conditions. More than ever individuals feel out of control of even the most elementary aspects of their lives. We must remember that earlier civilizations and cities simply fell apart when things went wrong.
For the longer term I hesitate to speculate. In The Vanishing Face Of Gaia James Lovelock shows how the self regulatory relationship between living organisms and their environment could break down. The subtitle of his book is A Final Warning, applied particularly to humans. Human communities and their concentration in cities may continue in one form or another, but not necessarily in the way we would like. The human species may even change its shape, assuming some are still alive to tell the tale. For example, given the evolutionary significance of our brains and the current hazards of childbirth, we might imagine a sort of human marsupial in which women gave birth earlier in the reproductive process, and developed a kind of pouch.
Supposing our species fell victim to some natural disaster, as other species have done in the past and will in the future, how long would it take for the Earth to recover from the human impact? How soon would our cities fall apart, the soils regenerate, the animals and plants we have favoured find a more normal place in the natural environment, the waters and seas become clearer, the chemistry of the air return to what it was before we polluted it? Life itself, from the bottom of the seas to the top of the atmosphere, is so robust that the human experience could become little more than a short and certainly peculiar episode in the history of life on Earth.
Above all let us remember how small and vulnerable we are as creatures of a particular environment at a particular moment in time. We are like microbes on the surface of an apple, on an insignificant tree, in an insignificant orchard, among billions of other insignificant orchards stretching over horizons beyond our sight or even our imagining.