Rising resource use threatens future growth, warns UN
The world is set to consume three times more natural resources than current rates by the middle of the century, according to a United Nations report.
It predicts that humanity will annually use about 140 billion tonnes of fossil fuels, minerals and ores by 2050.
The authors call for resource consumption to be "decoupled" from economic growth, and producers to do "more with less".
Growth in population and prosperity are the main drivers, they observe.
The report is the latest in a series by the UN Environment Programme's (Unep) International Resource Panel.
"Decoupling makes sense on all the economic, social and environmental dials, " said Unep executive director Achim Steiner.
"People believe environmental 'bads' are the price we must pay for economic 'goods'.
"However, we cannot and need not continue to act as if this trade-off is inevitable."
Co-lead author Mark Swilling from the University of Stellenbosch, South Africa, explained what would drive the surge in demand for resources.
"The reality is that there is another billion middle-class consumers on the way as a result of rapid industrialisation in developing countries," he told BBC News.
"If the resources required to generate these goods and services are used as efficiently as they currently are, then you are looking at that massive growth to 140 billion tonnes."
Professor Swilling added that population growth also played a role in the projected increase.
"If you add one Indian to the global population, you are talking about adding up to four tonnes of resource consumption each year. If you add an average Canadian, then you are adding another 25 tonnes," he explained.
"Developed world populations are stable, and some are even falling, so the real challenge... is in the developing world."
'Global test case'
The projection is based on data on four key resources: minerals, ores, fossil fuels and biomass.
Global average annual per capita consumption in 2000 was 8-10 tonnes, about twice as much as in 1900, the report said.
The combination of population growth, continuing high levels of consumption in industrialised countries, and increased demand for material goods - particularly in nations such as China, India and Brazil - saw total resource use grow eight-fold in the 20th Century.
Decoupling of economic growth and resource consumption is occurring, the authors observe, but not quickly enough.
They describe China as a test case "because it wants to continue its rapid economic growth, but use resources more sustainably".
"The measures that China introduces to reconcile these objectives will be of crucial significance for every other developing country with similar policy intentions," they add.
Professor Swilling acknowledged that the need to use the planet's finite natural resources more efficiently was not a new concern, but added he had "huge optimism" because of one recent emerging factor.
"Prices for resources between 1900 and 2000 fell in real terms," he explained.
"From 2000, resource prices have started going up and there is a consensus among economists that this is not a blip but probably the beginning of a long-term trend.
"It is still assumed that we live in a world with declining resource prices, and rising resource prices is so new that we have not yet configured it into mentality when it comes to economies.
"Price signals are good when it comes to trying to shift policies and recognise the need for resource efficiency - I think there is a new ball game afoot."
He suggested that policymakers must ensure that developing nations reconsidered their development strategies - "especially how they configure the infrastructures" for energy, water, transportation and sanitation.
"How we design and construct those infrastructures will have a major impact on the way resources flow through economies."
In the report's three scenarios, the most optimistic one would see annual per capita consumption return to 2000 levels, with 50bn tonnes being consumed each year.
But the authors acknowledge that the measures required to deliver that scenario would be so restrictive and unappealing to politicians that it is almost a non-starter.
They also admit that even this scenario is too little for some scientists, who feel it would not cut consumption and associated emissions to sustainable levels.
Responding to the report's findings, Simon Ross, chief executive of Population Matters (formerly known as the Optimum Population Trust), said continued global population growth and the continual rise in consumption was "impossible in the long-term and devastating to our environment in the short-term".
"We should seek to improve resource productivity and move to more equitable consumption levels," he told BBC News.
"However, the easiest and cheapest contribution to sustainability is promoting the existing trend to smaller families, and providing universal access to family planning to allow people to limit the number of children they have."
Professor Swilling said that rapid industrialisation offered another opportunity to improve resource efficiency - urbanisation.
"We are in the middle of what we refer to in the report as the 'second urbanisation wave', which is resulting in three billion people living in cities," he observed.
"The largest growth in urbanisation will be in developing countries; so a lot, again, is going to depend upon how we understand cities in developing nations and how we plan them, and how we accommodate large numbers of people.
"The advantage of cities is that they deliver a quality of life with fewer resources than the same quality of life outside of cities; cities are potentially key for the more efficient use of resources, and they are also melting pots for innovation."
A spokeswoman for Defra, the UK government's environment department, said a recent report showed that, in Britain alone, businesses could save about £18 billion by using raw materials more efficiently and generating less waste.
"Becoming more resource efficient contributes to a business's bottom line, increases profitability and their capacity to grow," she told BBC News.
"In addition to improving competitiveness, businesses could reduce carbon emissions by 29 million tonnes a year; so it's a win-win for business and the environment."
The Unep International Resource Panel said it planned to focus future reports on ways to "improve productivity and find viable alternatives for policymakers".
The next report is expected to be published in early 2012.