After two decades of talks that failed to slow the relentless pace of global warming, negotiators from almost 200 countries are widely expected to sign a deal in the next two weeks to take concrete steps to cut emissions.
The prospect of progress, any progress, has elicited cheers in many quarters. The pledges that have already been announced “represent a clear and determined down payment on a new era of climate ambition from the global community of nations,” said Christiana Figueres, executive secretary of the United Nations Framework Convention on Climate Change, in a statement a month ago.
Yet the negotiators gathering in Paris will not be discussing any plan that comes close to meeting their own stated goal of limiting the increase of global temperatures to a reasonably safe level.
They have pointedly declined to take up a recommendation from scientists, made several years ago, that they set a cap on total greenhouse gases as a way to achieve that goal, and then figure out how to allocate the emissions fairly. The pledges countries are making are voluntary, and were established in most nations as a compromise between the desire to be ambitious and the perceived cost and political difficulty of emissions cutbacks.
In effect, the countries are vowing to make changes that collectively still fall far short of the necessary goal, much like a patient who, upon hearing from his doctor that he must lose 50 pounds to avoid life-threatening health risks, takes pride in cutting out fries but not cake and ice cream.
The scientists argue that there is only so much carbon — in the form of exhaust from coal-burning power plants, automobile tailpipes, forest fires and the like — that the atmosphere can absorb before the planet suffers profound damage, with swaths of it potentially becoming uninhabitable.
After years of studying the issue, the experts recommended to climate diplomats in 2013 that they consider the concept of a “carbon budget” to help frame the talks. Yet the idea was quickly dismissed as politically impractical, and more recent pleas from countries like Bolivia to consider it have been ignored.
If any serious push had been made ahead of Paris to divvy up the emissions budget, the negotiators “would have all run screaming from the room,” said Michael A. Levi, an energy expert at the Council on Foreign Relations, in New York. “So that’s not a real alternative.”
The carbon budget will probably not get much attention in Paris for simple reasons.
Wrestling with a budget would, for instance, throw into stark relief the global inequities at the heart of the climate crisis. And it would underscore just how big the problem really is, how costly the delay in tackling it has been and how inadequate the plans being discussed in Paris are for limiting the risks.
Consider, for example, that Europe, the United States and China have offered emissions-reduction pledges that are their most ambitious ever. And yet, if their plans are carried out, a recent analysis suggests those regions will use up most of the remaining room for emissions in the atmosphere, leaving relatively little for the other five billion people on the planet or their descendants.
To change that equation, the biggest polluters would have to commit to cutting their emissions at rates that would be difficult to achieve, potentially disruptive to their economies and politically unrealistic.
Moreover, any serious discussion of the carbon budget would amplify a point of serious contention, known as “climate injustice,” in the talks. It refers to the idea that poor countries bear little past responsibility for climate change but are first in line to suffer its consequences, without much capacity to protect themselves.
Many of those same countries want to develop their economies by burning some fossil fuels, but because decades of high emissions by richer countries have created such profound risks, they are under pressure to adopt costlier green energy instead.
The idea of a carbon budget is based on a goal that the nations of the world set for themselves. In hopes of heading off the worst effects of climate change, they agreed in Cancún in 2010 to try to keep the warming of the planet to no more than 3.6 degrees Fahrenheit, or 2 degrees Celsius, above the level that prevailed before the Industrial Revolution.
Many scientists do not believe that such a limit would be particularly safe — it may still cause the sea to rise 20 feet or more, for instance, over a long period — but they agree that going beyond it would certainly be disastrous, precipitating an even larger rise of the sea, catastrophic heat waves, difficulty producing enough food and many other problems.
A series of scientific papers in 2009 demonstrated that limiting the temperature increase to 3.6 degrees Fahrenheit could be achieved by calculating the total amount of carbon dioxide and other greenhouse gases that could be emitted into the atmosphere before emissions needed to stop. The United Nations committee that periodically reviews climate science, the Intergovernmental Panel on Climate Change, highlighted the idea in a report it issued in Stockholm in 2013.
The group calculated a budget that can be thought of as something like — to use another food metaphor — a carbon pie, with the central question being: How can it be carved up fairly?
The problem is that about two-thirds of the pie has already been eaten by a handful of rich countries, plus China. At current rates, the remainder of it will be gone in 30 years or less. Many poor countries are crowding around the table, pleading for a sliver, but the big emitting countries insist on laying claim to most of the rest of the pie.
It is already clear, based on analyses published recently by several groups, that the pledges to cut emissions will come nowhere close to meeting the carbon budget. Many negotiators are pushing for a mechanism in which countries would gradually ratchet up their commitments to cutting greenhouse gases over time. But that would entail more delays, and it is not certain the carbon limit can be met that way.
Given the political realities, some of the scientists involved in devising the budget have resigned themselves to seeing it ignored in this round of negotiations, with the hope that countries will accelerate their efforts in coming years.
Myles R. Allen, a climate scientist at Oxford University and a leading proponent of the budget idea, said it was better for countries to keep negotiating than not. “It was probably the right call to brush it under the carpet for now,” he said.
Though it will be ignored in Paris, the idea of a carbon budget is gaining currency in the broader world of climate-change politics. For instance, the notion is at the heart of the student-led movement urging college endowment funds and other investors to shed their holdings in fossil-fuel companies. The students’ argument is not just that the companies are blocking needed change, but that they represent risky investments, given that much of the fossil fuels they hold as reserves cannot be burned if the world intends to stay within the carbon budget.
The same idea was at the heart of a speech recently by Mark Carney, the head of the Bank of England, who cited the potential economic risks of “unburnable carbon,” as it has become known. It is even an element of a recently disclosed investigation by the New York attorney general, who is studying whether Exxon Mobil and other companies have properly disclosed to investors the possibility that they may not be able to burn all their reserves.
Yet, within a month of the adoption of the carbon budget, as part of the Stockholm report two years ago, the idea of using it in the global negotiations had been dismissed out of hand. “I don’t think it’s possible,” Ms. Figueres, of the Framework Convention on Climate Change, told The Guardian newspaper that fall.
Yet, within a month of the adoption of the carbon budget, as part of the Stockholm report two years ago, the idea of using it in the global negotiations had been dismissed out of hand. “I don’t think it’s possible,” Ms. Figueres, of the Framework Convention on Climate Change, told The Guardian newspaper that fall. “Politically it would be very difficult.”
Some country or group of countries may well try to inject the carbon budget into the Paris talks. But most delegates are so unenthusiastic about the concept that it is likely to be quickly dismissed. Dr. Levi, of the Council on Foreign Relations, is among the realists about what can be achieved in the negotiations.
“The only way you can assess foreign policy is by asking, is what we’re getting better than something else?” Dr. Levi said in an interview. “I don’t see a better deal out there.”
