RIO DE JANEIRO – The 2012 Earth Summit is less than four days out, and nobody appears to have any idea how things are going to come together. The goals are hardly ambitious: produce a simple statement regarding humanity’s commitment to sustainable development, register a series of voluntary commitments by governments, businesses and anybody else who cares to sign up, and perhaps launch formal negotiations on a few key issues. It’s not like anybody is proposing a new treaty, but the world has yet to exorcise ghosts that have haunted environmental talks dating back to the original Earth Summit in 1992.

Negotiators began Wednesday with an 81-page text (based on the “zero draft” document circulated earlier this year) rife with brackets indicating options and disagreements, and UN officials said Friday afternoon that several working groups have only been able to achieve conditional agreement on some 28 percent of the text. “What really worries now is that the talks have completely stopped,” says Adrian Dellecker, manager of global and regional policy for WWF International in Switzerland. “We are clearly not ready for the heads of state.”

Although multiple working groups continued going through the motions Friday, developing countries put on the brakes due to fundamental disputes over trade and financial aid. Seemingly benign language referring to a “green economy” drew objections from major developing countries that fear restrictions on their ability to raise their citizens out of poverty. The concept of sustainable development stands on three pillars – economic advancement, environmental sustainability and social justice. Dellecker says many poor countries fear that talk of a green economy leaves out the social pillar.

The final round of official preparatory talks fizzled out late Friday evening, and many observers were left hoping the Brazil has plan for kick-starting the talks and producing a viable document before government leaders arrive next week. But if that is the case, the head of the Brazilian delegation certainly did a good job of playing things down Friday evening. “Brazil doesn’t have any text up its sleeves,” said Luiz Alberto Figueiredo. “We don’t have any surprises.” Figueiredo said Brazil would continue hosting informal talks over the weekend and into next week.

Monetary and legal commitments aside, one of the main discussions has been over UN Secretary-General Ban Ki-Moon’s call for sustainable development goals that would succeed the Millennium Development Goals, which expire in 2015. The idea has gained momentum among many who say the current commitments have served as useful international benchmarks, but it’s not yet clear whether Rio will do anything more than call for talks on the matter.

Planetary boundaries, or the doughnut

Coming into Rio, European officials initially sought to include a specific reference to “planetary boundaries”, an idea proposed by Johan Rockström and colleagues in Nature in 2009. The team sough to quantify critical global environmental thresholds in nine areas – ranging from climate change and biodiversity loss to the nitrogen and phosphorus cycles – in an effort to prevent dangerous large-scale environmental shifts. These ideas are explored further in a recent special edition of Nature dedicated to the Earth Summit.

The notion of including planetary boundaries into a political text is controversial even in the scientific community, as evidenced by a recent Nature commentary by Simon Lewis, and the idea appears to have been dropped for now. But it had its supporters as well, including one Oxfam researcher who said the space defined by the planetary boundaries and a tenth human dimension looks a bit like a doughnut.

“I wish there was something about what scientists are telling us is happening with the planet,” added Diana Liverman, co-director of the University of Arizona’s Institute of the Environment in Tuscon, following the formal unveiling of the Future Earth science initiative on Thursday. Planetary boundaries could have served as a placeholder for the science, she says. “The key is what the biosphere is telling us, and it’s not telling us good things.”

Speaking after the same event, Rockström said he has not been lobbying for the idea in Rio but believes it would be useful for governments to formally acknowledge that there are physical limitations in more areas than just climate change. He is also disappointed that much of the opposition (in addition to the United States) came from developing nations, which would benefit from the notion that there are limited resource and ecological spaces that must ultimately be shared by all. Regardless of how things turn out in Rio, the fact that this discussion is happening at all, he says, ” is a good sign.”

A law for the high seas?

Lastly, environmentalists are reporting some progress on ocean policy. Whereas prior environmental summits have largely ignored the oceans, the negotiators are now considering language on sustainable fisheries, illegal fishing and perverse industry subsidies. Moreover, they are also considering language that would call for negotiations for a new protocol to the Law of the Sea that would establish a framework for international governance on the high seas.

“Sixty four percent of the planet is without any governance at all,” says Sue Lieberman, deputy director of the Pew Environment Group in Washington. The language under discussion isn’t going solve all of the problems facing the oceans, Lieberman adds, “but it’s a step in the right direction.”