Representatives from around the world gather in Rio in June to try to hammer out goals for sustainable development at a U.N. conference designed to avoid being tripped up by the intractable issue of climate change.
But there is concern in the lead-up to the conference, known as Rio+20 or the Earth Summit, that it risks ending up as all talk and little action.
In an attempt to avoid too much confrontation, the conference will focus not on climate change but on sustainable development - making sure economies can grow now without endangering resources and the environment for future generations.
U.N. conferences over the past decade have begun with high hopes for agreements to compel nations to cut climate-warming emissions and help adapt to a hotter world, but they often ended with disappointingly modest results. That was the case last year in the global climate change summit in Durban, South Africa. Participants at that meeting agreed to forge a new deal by 2015 that would go into force by 2020.
The "sustainable" branding for this year's summit, rather than climate, is by design, said Ambassador Andre Correa do Lago, who headed Brazil's delegation to the U.N. climate talks in Durban and will be a chief negotiator for Brazil in Rio.
Sustainable development is an easier sell globally than climate change, even though sustainable development is a way of tackling global warming and other environmental issues, he said.
"Climate change is an (issue) that has very strong resistance from sectors that are going to be substantially altered, like the oil industry," do Lago said. "Sustainable development is something that is as simple as looking at how we would like to be in 10 or 20 years."
The time seems ripe. Natural resources are at a premium. The global human population tops 7 billion. Traditional economies are failing. And the planet is warming. Leaders may accept the premise that it makes sense to ensure rich and emerging nations can grow without further damaging the environment.
The focus of global meetings has been on the reduction of greenhouse gas emissions, especially carbon dioxide, but the world's biggest emitters, including China and the United States, have balked, arguing it would cripple economic development.
Climate change first claimed the world stage at the U.N. Earth Summit in Rio de Janeiro 20 years ago. That first Earth Summit in 1992 ultimately led to the carbon-capping Kyoto Protocol and a treaty on biodiversity.
This summit offers a chance to renew political will to make the world's economies greener.
Since the 1992 summit, successive attempts to secure a new binding pact to cut greenhouse gas emissions have failed to produce concrete results, public interest in climate change has waned, and many world leaders are concentrating on upcoming elections and financial worries.
"A MISSED OPPORTUNITY"
There is concern that this new summit could fall short.
"The most it will manage is to set some voluntary goals with a vague timeline, but it will not be clear what the process is to achieve these goals," said Andrew Light of the Centre for American Progress think tank in Washington. Without real goals and a way to reach them, Light said, Rio "will be a missed opportunity."
A U.N. draft document was released this month as a starting point for the June conference, outlining seven issues including jobs, energy, food, water and disasters.
"Without clearly defined goals, the summit will not provide the clarity and certainty that are needed to get the private sector to actively participate and potentially make the investments needed to achieve the goals," said Stephen Starbuck, expert on climate change and sustainability at Ernst & Young.
A narrower climate focus could also put off some countries, such as the United States, where opposition to carbon-capping legislation was so strong from Republicans and the oil industry that it overturned plans for a national emissions cap-and-trade arrangement.
In the past 20 years, the debate has changed as the world has changed, according to Tim Wirth, a former U.S. senator who attended the 1992 Rio meeting and will be at this year's conference as president of the non-profit U.N. Foundation.
"The debate's changed because of China, India, Brazil and South Africa, the very rapid and surprisingly powerful growth of the newly industrialized countries," he said.
In 1992 and in the Kyoto Protocol that grew from events at Rio, these developing countries and others were exempt from curbing carbon dioxide emissions, while rich countries like the United States would have had to cut back. In the end, the U.S. Senate never ratified the Kyoto Protocol, which entered into force in 2005.
"Rio was really exploratory," Wirth said. "Nobody knew what this was going to be all about. ... I think Rio+20 becomes an opportunity to be very specific, especially about energy and development."
Although fast-developing economies are eager for this shift, Wirth said there may be resistance from big energy powers like the United States and some oil producers in the Middle East.
"These are the countries that say, 'Hey, this is our sandbox, you can't get into it,'" he said. "But I think that's passing by very quickly."
Rio+20 will have to give the private sector the clarity and incentives they need over the medium term, Starbuck said.
Any goals set in Rio would likely be for the next 20 years, which could be too far in the future for most chief executives whose time in office is more likely to last years, not decades.
Instead, interim goals set along the way to 2030 would make the private sector more likely to engage, Starbuck added.