n one ecosystem and one planetary cycle after another, our impact already exceeds what is sustainable in the long run. We risk not only damaging the diversity and beauty of our natural environment, but endangering the resources and environmental services on which our welfare and survival depend.
The challenge ahead is decisive. It depends critically on what happens to population, consumption and technology, and all the political, social and economic factors that influence them.
Over the next half century, world population is projected to grow by one half. Consumption per person, if it continues at the rate of recent decades, will roughly double. So the overall scale of the world economy, the sum of our demand for products and services, is likely to multiply by around three times. If our current level of efficiency in resource use and waste output were to remain unchanged, then our environmental impact by 2050 would be three times greater than today, even if we did not cross any dangerous thresholds relating to oceans and atmosphere.
Determined action will be needed to bring our impact down to sustainable levels. It will be needed on all three elements -- population, consumption and technology -- and on all the policies, institutions and values that affect them. [Add]
The days when the fertility of hundreds of millions of women could be regarded as a useful instrument of environmental policy are over. Women and their partners make their own decisions about how many children to have.
Nevertheless, governments can help to create the conditions where having fewer children will make sense, and where people have the means to reach their desired fertility. And if fertility can be reduced, there will usually be environmental benefits.
Considerable progress has been made in the past decade in reducing fertility and slowing future population growth rates. The greatest scope for further progress lies in those countries and areas where fertility is still high -- in the northern parts of South Asia, much of the Middle East, and sub-Saharan Africa. While more than 60 percent of Asian and Latin American women were using some form of contraception in the late 1990s, the figure for Africa was only 20 percent . [Add]
By and large the countries where there is scope for faster progress are also countries that are likely to face severe human and environmental problems from rapid population growth -- land degradation in sub-Saharan Africa, water shortages in the Arab world, and land shortages in South Asia.
Provision of good quality family planning with a choice of methods can have a considerable impact on women's fertility, but the greatest effect is achieved when this is combined with a broad range of measures to improve mother and child health, women's literacy and education, and women's rights more generally. These measures are win-win solutions. All of them are valuable in their own right. Improving human welfare will always be the primary rationale for pursuing them -- but the environmental spin-offs come as an added bonus. [Add]
The consumption factor is perhaps the toughest one to tackle. The poor of the Earth desperately need to increase their incomes. In 1997 the poorest 2 billion people in the world had average real incomes of only US$1 400 -- less than a quarter of the world average and a mere 6 percent of the high-income country average .
But even in countries with middle and high incomes people have come to expect steadily increasing prosperity. No politician can hope to get elected on a platform of reducing consumption: leaders who preside over periods of slower economic growth often fail to get re-elected.
A more realistic approach is to divert consumption into channels with lower environmental costs, while ensuring that people still enjoy the end products or services they need for dignity and comfort. The balance of taxes and subsidies can be shifted so as to make environmental "bads" like excessive car or fossil-fuel use less attractive to consumers, and environmental "goods" such as energy-saving technology more attractive.
The Internet, by enabling more people to work from home or shift information and services electronically rather than physically, is reducing the resource requirements of industry and especially services. Changes in culture and values, such as the movement for a simpler, more environmentally friendly lifestyle, are also having an impact on consumer behavior . [Add]
Inevitably, the heaviest burden will fall on the technology element of the equation. If, as is quite likely, the scale of the world economy trebles by 2050, then technological changes will have to reduce the environmental impact of our activities by two thirds -- just to prevent the present rate of damage from increasing.
Since our impact is already unsustainable, the Club of Rome has proposed a Factor Four improvement in resource efficiency (that is, a 75 percent reduction in resource use per unit of production) .
However, in the long run that would produce an impact only 25 percent below the present unsustainable level, and may be too modest a target. More probably we need something approaching a Factor Ten reduction -- that is, we would reduce by 90 percent the amount of resources and wastes produced for each unit of consumption, while eliminating poverty and maintaining reasonable standards for all. To reach this target by 2050 would require a 4.5 percent reduction per year. To reach it by 2100 would require a 2.3 percent reduction per year.
Though these rates are higher than those achieved in fuel efficiency over recent decades, we know that at times of technological breakthrough or crisis much faster rates of change are possible. For example, the achievable density of transistors on integrated circuits doubles every two years, an annual increase of 41 percent. Refrigeration technology shifted very rapidly away from the use of chlorofluorocarbons, with an average reduction in CFC production of at least 23 percent a year between 1986 and 1995 . [Add]
A wide range of policies is needed to encourage environmentally friendly technology. Many policies are specific to each different field or area and most are beyond the scope of this atlas.
More general approaches include:
All of these measures would go some way to ensuring that the pricing of goods and services reflects the true environmental costs, thereby encouraging more environmentally sound approaches to consumption and technological development. [Add]
Because the population, consumption and technology equation is a multiplication sum, actions that reduce any one component in isolation are necessary. However, there is also a range of measures for tackling population and environment jointly.
There was a time when international conferences avoided all explicit linking of population and environment. Conferences in the 1990s, from the United Nations Conference on Environment and Development in 1992 onwards, were much more willing to acknowledge the interaction. Yet the areas of population and environment are still seriously underfunded in development assistance, and the United Nations Environment Programme is one of the most impoverished UN agencies.
At the national level there is still ground to be made up. Although most national development plans, national sustainable development strategies and national environmental action plans make some mention of population, it is usually simply a token gesture: the potential contribution of population measures to easing environmental stresses is not usually acknowledged.
At local level there have been many successful integrated programs which encouraged communities to pursue sustainable approaches across the board from environment to population. Efforts to incorporate environmental elements into population and reproductive health programs, and vice versa, have been less successful. The best results for the environment are achieved when these programs focus on doing their core activities as well as possible. Burdening them with extra responsibilities may jeopardize this.
Finally, research into population-environment linkages at every level from village to planet can help to inform policy. International studies of global environmental problems, such as the Intergovernmental Panel on Climate Change reports, should include scenarios showing the potential impact of slower population growth. [Add]
A number of blockages and bottlenecks can slow our adaptive response to environmental challenges and make disastrous Malthusian outcomes more likely. Various steps can be taken to remove these blocks.
Environmental science and monitoring must be adequately funded. At a minimum we have to know what is going on, and understand the processes and interactions involved. Market imperfections that worsen environmental problems must be removed -- starting with the wide range of subsidies in many countries that encourage activities like fossil-fuel burning or overfishing.
Democratic imperfections need attention too: in less developed countries the people most affected by environmental change, who are usually the poorest, need better access to the political and legal system and to the media. In developed countries state funding of political parties and strict limits on election spending will reduce the influence of business and labor lobbies on government. Freedom of information must be strengthened to allow concerned citizens full access to important environmental data, whether held by governments or private companies.
Finally we need a shift in values towards nature conservation and lower resource use. This is happening spontaneously as environmental problems mount, not just in rich countries but in many developing countries.
If we can mobilize the full range of policy responses, then we can move towards a sustainable relationship with the environment within the next 50 years. The timing is critical: even a decade's delay could trigger threshold effects with incalculable consequences. [Add]