In a report published on Thursday by the London-based Royal Society, an international group of 23 scientists chaired by Nobel laureate Sir John Sulston called for a rebalancing of consumption in favor of poor countries coupled with increased efforts to control population growth to lift the estimated 1.3 billion people living on less than $1.25 a day out of poverty.

"Over the next 30-40 years the confluence of the challenges described in this report provides the opportunity to move towards a sustainable economy and a better world for the majority of humanity, or alternatively the risk of social, economic and environmental failures and catastrophes on a scale never imagined," the scientists said.

The 133-page report, which Sulston describes as a summary of work done over the last two years, comes against a backdrop of austerity-hit governments reducing subsidies for renewable energy, global car companies falling over themselves to meet demand for new cars in rapidly growing economies like China and Brazil, and increasing pressure to exploit vast reserves of gas locked in rocks around the globe through the controversial process known as ‘fracking'.

But the scientists insist the goals in the report are realistic. They argue lifestyle choices, human volition and incentives enshrined in government policy can make a significant difference to patterns of consumption.

They cite the growing appetite for recycling in the developed world, Britain's policy-driven switch to lead-free fuel in the 1980s, and the seemingly prosaic example of air traffic control as examples of where international cooperation can work.

Sulston said governments realized quickly that the consequences of not managing air traffic could be catastrophic: "They said 'this is dangerous; we've got to cooperate'."

The scientists say developed and emerging economies should stabilize and then start reducing their consumption of materials by increased efficiency, waste reduction and more investment in sustainable resources.

Carbon dioxide emissions are 10 to 50 times higher in rich countries compared to poor nations, they say. Rising greenhouse gas emissions are almost certainly responsible for increasing global average temperatures, leading to rising sea levels and more extreme weather, climate scientists say.

Voluntary programs to reduce birth rates, education for young women and better access to contraception urgently need political leadership and financial support.

Professor Sarah Harper of Oxford University, another of the authors, said the issue of population had fallen off the development agenda in the last 10-15 years but it should be reinstated and coupled closely with environmental challenges, starting at the Rio+20 United Nations Conference on Sustainable Development to be held in Rio in June.

WANTED: BRAVE POLITICIANS

The trend to urbanization remains intact. Some 50 percent of the world's population, which surpassed 7 billion last year, is living in cities. The world's population is forecast to rise to 10 billion before flattening off and the urban proportion is forecast to increase to 75 percent by the end of the century.

Eliya Msiyaphazi Zulu, a report author and Executive Director of the African Institute for Development Policy research group, said the need for education about family planning and improved access to contraception was most acute in Africa, which is forecast to contribute 70 percent of the average population growth.

He said all the evidence points to African women wanting fewer children and argued the main reason for high fertility in a country like Niger was the fact that half of all women are married at the age of 16.

The scientists also supported growing calls for a revision in how we measure economic growth. "We are extremely wedded to the idea that GDP increases are a good thing," said Jules Pretty, Professor of Environment and Society at the University of Essex and another of the authors.

He argued that GDP measures many of the ‘bads' in terms of the well-being of the planet as well as the ‘goods', adding: "There is an urgent need for policy change."

The scientists present some startling statistics. A child from the developed world consumes 30-50 times as much water as one from the developing world. Global average consumption of calories increased about 15 percent between 1969 and 2005, but in 2010 almost 1 billion people did not get their minimum calorie needs.

Minerals production rocketed in the 47 years up to 2007; copper, lead and lithium about fourfold and tantalum/niobium, used in electronic gadgets, by about 77 times.

For developed countries, Sulston said the message of the report boils down to something quite simple: "You don't have to be consuming as much to have a healthy and happy life".

But will politicians and consumers respond?

"It is a brave politician who is prepared to tell Western consumers to consume less to let the developing world consume more," said Tim Lang, Professor of Food Policy at City University in London. "But we need such bravery now, urgently."

Lang, who was not involved in the study, welcomed it saying: "The West over- and mal-consumes its way to diet-related ill-health from a diet with a high environmental impact. The evidence is there but will politicians and consumers listen and change?"

(Editing by Janet Lawrence)

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