As the Rio+20 Conference on the environment enters its last day, two things are certain. With its negotiated text finalised and awaiting formal approval by heads of state, the conference will not -- like the Copenhagen climate conference in 2009 -- run desperately over time, threatened by brinksmanship, courting collapse. Nor will it deliver anything of significance. Rio+20 is a zombie summit, shuffling through its paces dead-eyed, toothless, empty-handed. It is a ritual that lacks a clear agenda or international commitment to action. Its 53-page, 283-clause draft text can rightly be criticised as a pastiche of platitudes winnowed of substance during pre-negotiations. Gone are notions of planetary limits critical to the raison d’etre for this conference. Gone is any tough response to the crisis of the oceans -- as dramatic and urgent as that of our atmosphere. With no clear goals, no new treaties, no new funding, Rio+20 merely commemorates the monumental initiatives of the original 1992 Rio Earth Summit rather than proposing significant new ones. By contrast, the 1992 summit -- formally, the UN Conference on Environment and Development -- was propelled by hope. Everyone hoped that the end of the Cold War and its arms race would produce a "peace dividend" that could solve the world’s most pressing problems of environmental degradation and poverty. Like Rio+20, that conference was also marked by tensions between the developed and developing world. The latter wanted a radical redistribution of global wealth as the "price" for agreeing to participate in two new major treaties on climate (the UN Framework Convention on Climate Change) and biodiversity preservation (CBD). Twenty years on, the same issues and tensions remain unresolved but greater. Nowhere is this evidence clearer than in the UN Environment Program’s authoritative fifth scientific Global Environmental Outlook Report -- the GEO 5 -- presented to the Rio+20 Summit. This report indicated that planetary boundaries and limits have now been breached. Our global environmental health -- measured against 40 major indicators -- is rapidly failing. Of the major planet-threatening issues, global warming and its impacts are accelerating, as is biodiversity loss. This must be the definition of a global environmental crisis. The developing bloc’s concerns about development and "poverty eradication" have grown. Many related indicators also point to deteriorating social and economic conditions since 1992. Most millennium development goals set to address them by 2015 are unlikely to be met. In fact, as a consequence, the environment has been reduced to a backstage prop to human development concerns in much of the Rio+20 draft text, The Future We Want. Two decades ago, there was hope that the looming ecological crisis and tensions between environmental protection and development could both be resolved by well-funded application of the idea of "sustainable development", freshly minted by the UN’ s Brundtland Report in 1987. This hope was framed and given substance in Agenda 21 and the Rio Declaration, and the Commission on Sustainable Development, that accompanied it. Since then, "sustainable development" has been reduced to a tired cliché, Agenda 21 set aside, and the CSD poorly funded. A key element to the specific failure of Rio+20 has been its failure to generate a new, coherent and powerful analysis of the economic and environmental failures of the past two decades, and then to respond to this critique. Rio+20 comes at an extraordinary historical conjuncture. Days apart, two global summits have attempted to address compounding economic and environmental crises. It is only a relatively short distance from Mexico to Brazil for some of the heads of the G20, including Julia Gillard, who have flitted from one forum to the next. The deep failures of both summits are closely linked. The G20 leaders have desperately sought to stabilise the European economies -- to avert the sort of acute crisis that we saw in 2008 -- by managing debt, in order to generate renewed growth. For the moment, stabilisation may seem within their grasp -- a shallow success that certainly gives us temporary relief from immediate chaos. Rio+20 and the G20 Summit confront a linked crisis -- the global consequences of poorly regulated economic growth and the over-consumption of natural resources. Both aspects have been produced by failures of national and international governance -- exacerbated by neo-liberal globalisation -- to limit debt and environmental over-exploitation to sustainable levels. The solution sought by the G20 (and Germany in particular) is temporary austerity in order to reinvigorate conventional economic growth and trade. And so the solution offered by one summit promises merely a return to the trajectory of environmental depletion that the second summit tries to end. It makes you wonder what the leaders are thinking as they shuffle between Los Cabos and the Rio Summit. The key pre-Rio+20 documents contributed by the OECD and the UNEP attempted to revive the notion of sustainable development within a "green growth" paradigm. However the notions of "green growth", "green economics" and "free trade" at the heart of the Rio+20 message still fundamentally rely, as the draft text Future We Want puts it, on "promoting sustained, inclusive and equitable economic growth" and increasing "sustainable consumption". All this disregards and intensifies the degradation of the planet’s environmental "base". The harder and necessary path is to further reduce aggregate global demand for material goods, the dematerialisation approach that Tim Jackson, a former member of the UK Sustainability Commission, called "prosperity without growth" in his report of the same name. What would a global economy based on shrinking material consumption to respect planetary boundaries actually look like? How would employment be maintained? How would redistribution of wealth and resources occur within and between states in such a global economy? What is required to remove all state support and subsidies for environmentally destructive activity? Or to ensure that trade is constrained by environmental restrictions? How could political and economic constituencies be built to support and engage in this transformation? These shifts imply and frame a new global order very different from that embodied in the Los Cabos Growth and Jobs Action Plan or the weak text of The Future We Want that Rio will bless. Such an alternative just might catalyse a future that we could really want -- or at least be able live with over time. But zombie summitry will never produce such deals or outcomes. *Associate professor Peter Christoff teaches environmental policy at the University of Melbourne. He is also vice-president of the Australian Conservation Foundation.