Countries meeting at the United Nations climate change conference may be closer than some observers realise to agreeing the emissions cuts required to give the world a reasonable chance of avoiding global warming of more than 2˚C, according to an analysis launched today (6 December) in Copenhagen by Nicholas Stern and the United Nations Environment Programme (UNEP).

An analysis of national proposals for annual emissions reductions, published on the eve of the UN climate change conference, indicates that the gap between countries’ strongest proposed cuts and what is needed may be only a few billion tonnes of greenhouse gases.

The study has been compiled by Lord Stern of Brentford, chair of the Grantham Research Institute on Climate Change and the Environment at London School of Economics and Political Science, in collaboration with analysts at UNEP.

The emissions reductions gap identified by the analysis, however, would require a number of key conditions, in particular that developed countries provide developing countries with the right level of financial and technical support for both emissions reductions and adaptation in the most vulnerable countries and communities in the developing world.

It also requires that countries deliver on their commitments and intentions, and interpret the actions of others as sufficient to meet any conditions they may have set.

The research estimates that in order to have a reasonable chance, or 50 per cent probability, of avoiding a rise in global temperature of more than 2˚C, annual global emissions of greenhouse gases in 2020 need to be no more than 44 billion tonnes of carbon-dioxide-equivalent.

The analysis shows that the gap between this target and the most ambitious cuts proposed by countries over the past months and weeks is about 2 billion tonnes of carbon-dioxide-equivalent, with a range of 1 to 5 billion tonnes. If the overall target 44 billion tonnes is exceeded in 2020, it is likely to be more difficult and costly to reach the goal as much stronger action would be required in decades afterwards.

The gap could be filled during negotiations in Copenhagen by combining several additional actions including:

  • Developed countries increasing their high intentions.
  • Key developing countries offering more than their existing proposals, particularly in the context of serious international support for the developing world, covering both adaptation and mitigation.
  • Additional reductions from deforestation and other sources, and in particular international commitments to support and enhance the national efforts of countries such as Brazil and Indonesia.
  • Incorporating international emissions from aviation and shipping in order to deliver additional emissions reductions.

Lord Stern said: “No one should be under any illusion. Reaching the target to cut annual emissions to 44 billion tonnes in 2020, by bridging the remaining gap of a few billion tonnes, will require governments over the next two weeks and over the next few years to match words with deeds and ambition with action. If they do, we could embark on the most dynamic and creative period of the world’s economic history, a new energy and industrial revolution.”

“It should also be understood that the range of figures presented here are not fixed but are nevertheless a good indication of where we are and where we need to be by 18 December 2009.”

Achim Steiner, UN Under-Secretary General and UNEP Executive Director added: “What we are presenting here is underpinned by numerous provisos—not least that serious and sustained funding is provided to assist countries like Brazil and Indonesia to achieve the high end of their new proposals, and that all nations deliver on their pledges and promises.”

“Nevertheless having a reasonable chance of limiting a global temperature rise to no more than 2˚C can, with clearly designed policies applied consistently across countries and industries, be cost effectively met and can also set the stage for a low-carbon, resource-efficient 21st century Green Economy — that is the central message.”


Many scientists argue, including the Intergovernmental Panel on Climate Change (IPCC), that in order to avoid dangerous climate change, global temperatures must not rise more than 2˚C above pre-industrial levels.

Current greenhouse gas emissions are around 47 billion tonnes of carbon-dioxide-equivalent and would be at around 50 billion tonnes if the world had not gone through an economic slowdown. Without any action whatsoever, emissions of greenhouse gases would be in the mid-50 billion tonnes or higher by 2020.

To get the world on track, the science and economics indicate that annual global emissions of greenhouse gases by 2020 must be reduced, with this analysis suggesting a target of no more than 44 billion tonnes of carbon-dioxide-equivalent by that date.

An assessment of existing and new emissions proposals

The report has assessed most of the commitments and proposals that have emerged over recent months, including ones that have come forward in the past few weeks.

The report states: “Existing proposals from developed and developing countries constitute a big step towards a level consistent with the 2˚C goal. Taking countries’ highest intentions would take the world to around 46Gt (46 billion tonnes), which is around 80 percent of the way from business as usual.”

The most complicated part of the analysis is on the intentions of developing countries, many of which are also contingent on a variety of conditions being met by developed countries and on international finance.

Proposals by developing countries are also based on moving away from a ‘business as usual’ scenario and thus estimates of emissions are dependent on modelling what emissions might be at a certain date in the future if no action were taken.

The analysis also shows what might happen to emissions in 2020 if the proposed national efforts of countries such as Brazil, Indonesia and South Africa, as recently announced, are ‘fully supported’ by the international community.

The analysis suggests that, in one scenario based on current intentions, the total annual emissions from developing countries could, by 2020, stand at 28.9 billion tonnes of carbon-dioxide-equivalent. Annual emissions from developed economies, based on current commitments, could be 15.7 billion tonnes of carbon-dioxide-equivalent by 2020. Emissions from aviation and maritime sources could be 1.3 billion tonnes of carbon-dioxide-equivalent. The total would stand at around 46 billion tonnes of carbon-dioxide-equivalent.

Lord Stern added: “The intentions of developing countries must be given strong support. The world must focus in Copenhagen on this gap of a few billion tonnes. Economic analysis indicates that the longer we wait to bring emissions down, the more expensive it will be. It is vital too, and this must never be forgotten during the intense discussions on emissions reductions, to support adaptation to climate change in the most vulnerable countries and communities of the world.”

Notes for Editors

  1.  Nicholas Stern was Second Permanent Secretary at HM Treasury between 2003 and 2007. He also served as Head of the Government Economic Service, head of the review of economics of climate change (the results of which were published in ‘The Economics of Climate Change: The Stern Review’ in October 2006), and director of policy and research for the Commission for Africa. His previous posts included Senior Vice-President and Chief Economist at the World Bank, and Chief Economist and Special Counsellor to the President at the European Bank for Reconstruction and Development. He was recommended as a non-party-political life peer by the UK House of Lords Appointments Commission in October 2007. Baron Stern of Brentford was introduced in December 2007 to the House of Lords, where he sits on the independent cross-benches.
  2. The Grantham Research Institute on Climate Change and the Environment was launched at the London School of Economics and Political Science in October 2008. It is funded by The Grantham Foundation for the Protection of the Environment. Lord Stern is also Chair of the Centre for Climate Change Economics and Policy, which is hosted by the University of Leeds and the London School of Economics and Political Science. He is also I.G. Patel Professor of Economics and Government and Director of the India Observatory at London School of Economics and Political Science.
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