Peter Singer
The lives of billions of people, for centuries to come, will be at stake when world leaders and government negotiators meet at the United Nations Climate Change Conference in Paris at the end of the month. The fate of an unknown number of endangered species of plants and animals also hangs in the balance.
At the “Earth Summit” in Rio de Janeiro in 1992, 189 countries, including the United States, China, India, and all European countries signed on to the UN Framework Convention on Climate Change (UNFCCC), and agreed to stabilize greenhouse-gas emissions “at a low enough level to prevent dangerous anthropogenic interference with the climate system.”
So far, however, no such stabilization has taken place, and without it, climate feedback loops could boost rising temperatures further still. With less Arctic ice to reflect sunlight, the oceans will absorb more warmth. Thawing Siberian permafrost will release vast quantities of methane. As a result, vast areas of our planet, currently home to billions of people, could become uninhabitable.
Earlier conferences of the UNFCCC signatories sought to reach legally binding agreements on emission reductions, at least for the industrialized countries that have produced most of the greenhouse gases now in the atmosphere. That strategy faltered – partly owing to US intransigence under President George W. Bush – and was abandoned when the 2009 Copenhagen conference failed to produce a treaty to replace the expiring Kyoto Protocol (which the US never signed). Instead, the Copenhagen Accord merely asked countries for voluntary pledges to cut their emissions by specific amounts.
Those pledges have now come in, from 154 countries, including the major emitters, and they fall far short of what is required. To fathom the gap between what the pledges would achieve and what is required, we need to go back to the language that everyone accepted in Rio.
The wording was vague in two key respects. First, what would constitute “dangerous anthropogenic interference with the climate system”? And, second, what level of safety is assumed by the term “prevent”?
The first ambiguity has been resolved by the decision to aim for a level of emissions that would cap the increase in average surface temperature at 2º Celsius above the pre-industrial level. Many scientists consider even a lower increase dangerous. Consider that even with a rise of only 0.8ºC so far, the planet has experienced record-high temperatures, more extreme weather events, and substantial melting of the Greenland ice sheet, which contains enough water to cause a seven-meter rise in sea levels. In Copenhagen, the pleas of representatives of small island states (some of which will cease to exist if sea levels continue to rise) for a target of 1.5ºC went unheeded, essentially because world leaders thought the measures required to meet such a target were politically unrealistic.
The second ambiguity remains. The London School of Economics’ Grantham Research Institute has analyzed the submissions made by all 154 countries and concluded that even if they are all implemented, global carbon emissions will rise from their current level of 50 billion tons per year to 55-60 billion tons by 2030. But, to have even a 50% chance of keeping to the 2ºC limit, annual carbon emissions need to come down to 36 billion tons.
Read more at Project Syndicate
