From Nature magazine
The tropical air was charged with hope and despair as the world’s leaders descended on Rio de Janeiro for the United Nations’ Earth summit in May 1992. Countries were buoyed by a string of successful environmental treaties in the 1970s and 1980s, capped by a landmark deal to save the ozone layer in 1987. Yet the Earth summit in Rio, which drew 178 nations and around 100 heads of state, was also rife with frustration and distrust. Diplomats had spent the previous two years drafting a pair of treaties intended to safeguard Earth’s biodiversity and climate, but the talks had recently faltered as rich and poor countries split over who should pay for protecting the planet.
In the end, the leaders decided that they could not go home empty handed. They signed off on both the Convention on Biological Diversity and the Framework Convention on Climate Change, making broad pledges to solve some of the most complex problems facing humanity. Countries also agreed to a laundry list of goals spelled out in a document known as Agenda 21, which eventually spawned the Convention to Combat Desertification. Although the agreements lacked teeth, they created formal international processes that engaged almost the entire world and eventually led to more targeted accords (see ‘Global awakening’).
At the end of the summit, Richard Benedick, who had negotiated the ozone accord for the United States, told The New York Times that “the history books will refer back to this day as a landmark in a process that will save the planet from deterioration”. But he and others warned that progress would not come quickly.
The pace turned out to be far slower than anticipated, however. Although nations have made some marginal advances, the three conventions have failed to achieve even a fraction of the promises that world leaders trumpeted two decades ago. Dismal grades dominate Nature’s report cards on the Rio treaties, although the assessment also highlights some progress and offers pointers for the future. As diplomats and leaders prepare to converge on Rio this month for the UN Conference on Sustainable Development, or Rio+20, they will be looking back to consider how to do better.
Climate of inaction
The climate numbers are downright discouraging. The world pumped 22.7 billion tonnes of carbon dioxide into the atmosphere in 1990, the baseline year under the UN Framework Convention on Climate Change. By 2010 that amount had increased roughly 45% to 33 billion tonnes. Carbon dioxide emissions skyrocketed by more than 5% in 2010 alone, marking the fastest growth in more than two decades as the global economy recovered from its slump. And despite constant deliberations under the convention, the overall growth rate of global emissions hasn’t changed much since 1970 (see ‘Report card: UN Framework Convention on Climate Change’).
“Plausibly we are a little better off than if we didn’t have all of this diplomacy,” says David Victor, director of the Laboratory on International Law and Regulation at the University of California, San Diego. “But the evidence is hard to find.”
Ratified by 194 countries plus the European Commission, the treaty sought to stabilize emissions at a level that would “prevent dangerous anthropogenic interference with the climate system”. Although there were no specific targets, wealthy countries agreed to take the lead and help poor countries with monetary and technological aid. In 1997, negotiators followed up with the Kyoto Protocol, which entered into force in 2005 and committed industrialized countries to reduce their collective emissions of all greenhouse gases by 5.2% (compared with 1990) by 2012.