But without rising risks, shocks, scarcities and crises increasingly inherent in the existing, resource-depleting, high carbon ‘brown' economy, says the study. As such, it comprehensively challenges the myth of a trade off between environmental investments and economic growth and instead points to a current "gross misallocation of capital".

The report sees a Green Economy as not only relevant to more developed economies but as a key catalyst for growth and poverty eradication in developing ones too, where in some cases close to 90 per cent of the GDP of the poor is linked to nature or natural capital such as forests and freshwaters.

It cites India, where over 80 per cent of the $8 billion National Rural Employment Guarantee Act, which underwrites at least 100 days of paid work for rural households, is invested in water conservation, irrigation and land development.

• This has generated three billion working days-worth of employment benefiting close to 60 million households.

Two per cent of the combined GDP of Cambodia, Indonesia, the Philippines and Vietnam is currently lost as a result of water-borne diseases due to inadequate sanitation.

• Policies that re-direct over a tenth of a per cent of global GDP per year can assist in not only addressing the sanitation challenge but conserve freshwater by reducing water demand by a fifth by 2050 compared to projected trends.

The report has modeled the outcomes of policies that redirect around $1.3 trillion a year into green investments and across ten key sectors-roughly equivalent to two per cent of global GDP. To place this amount in perspective, it is less than one-tenth of the total annual investment in physical capital.

Currently, the world spends between one and two per cent of global GDP on a range of subsidies that often perpetuate unsustainable resources use in areas such as fossil fuels, agriculture, including pesticide subsidies, water and fisheries. Many of these are contributing to environmental damage and inefficiencies in the global economy, and phasing them down or phasing them out would generate multiple benefits while freeing up resources to finance a Green Economy transition.

In addition to higher growth, an overall transition to a Green Economy would realize per capita incomes higher than under current economic models, while reducing the ecological footprint by nearly 50 per cent in 2050, as compared to business as usual.

The Green Economy report acknowledges that in the short-term, job losses in some sectors-fisheries for example-are inevitable if they are to transition towards sustainability.

Investment, in some cases funded from cuts in harmful subsidies, will be required to reskill and re-train some sections of the global workforce to ensure a fair and socially acceptable transition. The report makes the case that over time the number of "new and decent jobs created" in sectors - ranging from renewable energies to more sustainable agriculture - will however offset those lost from the former "brown economy".

For example, investing about one and a quarter per cent of global GDP each year in energy efficiency and renewable energies could cut global primary energy demand by nine per cent in 2020 and close to 40 per cent by 2050, it says.

• Employment levels in the energy sector would be one-fifth higher than under a business as usual scenario as renewable energies take close to 30 per cent of the share of primary global energy demand by mid century.
• Savings on capital and fuel costs in power generation would under a Green Economy scenario, be on average $760 billion a year between 2010 and 2050.

The report, Towards a Green Economy: Pathways to Sustainable Development and  Poverty Eradication, also highlights enormous opportunities for decoupling waste generation from GDP growth, including in recovery and recycling.

• The Republic of Korea has, through a policy of Extended Producer Responsibility, enforced regulations on products such as batteries and tyres to packaging like glass and paper, triggering a 14 per cent increase in recycling rates and an economic benefit of $1.6 billion.
• Brazil's recycling already generates returns of $2 billion a year, while avoiding 10 million tones of greenhouse gas emissions; a fully recycling economy there would be worth 0.3 per cent of GDP.

The report, compiled by the UN Environment Programme (UNEP), in collaboration with economists and experts worldwide, takes meeting and sustaining the UN's Millennium Development Goals - ranging from halving the proportion of people in hunger to halving the proportion without access to safe drinking water - as one aim. Bringing down emissions of greenhouse gases to the much safer levels of 450 parts per million by 2050 is another overarching target.

The findings were presented to environment ministers from over 100 countries at the opening of the UNEP Governing Council/Global Ministerial Environment Forum. The report, part of a bigger macro-economic study published online, is aimed at accelerating sustainable development and forms part of UNEP's contribution to the preparation of the Rio+20 conference scheduled in Brazil next year.

Over the coming months UNEP's Green Economy team plans to present the report in capitals around the world. Here they also want to learn firsthand how best to assist countries and communities commence a transition to a Green Economy within their national circumstances. Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said: "The world is again on the Road to Rio, but in a world very different to the one of the Rio Earth Summit of 1992."

"Rio 2012 comes against a backdrop of rapidly diminishing natural resources and accelerating environmental change-from the loss of coral reefs and forests to the rising scarcity of productive land; from the urgent need to feed and fuel economies and the likely impacts of unchecked climate change," he added.

"The Green Economy as documented and illustrated in UNEP's report offers a focused and pragmatic assessment of how countries, communities and corporations have begun to make a transition towards a more sustainable pattern of consumption and production. It is rooted in the sustainability principles agreed at Rio in 1992, while recognizing that the fundamental signals driving our economies must evolve in terms of public policy and market responses," he said.

"We must move beyond the polarities of the past, such as development versus environment, state versus market, and North versus South," said Mr. Steiner. "With 2.5 billion people living on less than $2 a day and with more than two billion people being added to the global population by 2050, it is clear that we must continue to develop and grow our economies. But this development cannot come at the expense of the very life support systems on land, in the oceans or in our atmosphere that sustain our economies, and thus, the lives of each and everyone of us," he added.

"The Green Economy provides a vital part of the answer of how to keep humanity's ecological footprint within planetary boundaries. It aims to link the environmental imperatives for changing course to economic and social outcomes-in particular economic development, jobs and equity," said Mr. Steiner.

Pavan Sukhdev, on secondment from Deutsche Bank and head of UNEP's Green Economy Initiative, said: "Governments have a central role in changing laws and policies, and in investing public money in public wealth to make the transition possible.

By doing so, they can also unleash the trillions of dollars of private capital in favour of a Green Economy." "Misallocation of capital is at the centre of the world's current dilemmas and there are fast actions that can be taken starting literally today-from phasing down and phasing out the over $600 billion in global fossil fuel subsidizes to re-directing the more than $20 billion subsidies perversely rewarding those involved in unsustainable fisheries," he said.

"A Green Economy is not about stifling growth and prosperity, it is about reconnecting with what is real wealth; re-investing in rather than just mining natural capital; and, favouring the many over the few. It is also about a global economy that recognizes the intergenerational responsibility of nations to hand over a healthy, functioning and productive planet to the young people of today and those yet to be born," added Mr. Sukhdev.

Download the report: http://www.unep.org/greeneconomy/GreenEconomyReport/tabid/29846/Default.aspx