Rapid global economic growth, centred in Asia but now spread across the world, is driving rapid greenhouse-gas emissions growth, making earlier projections unrealistic. This paper develops new, illustrative business-as-usual projections for carbon dioxide (CO2) from fossil fuels and other sources and for non-CO2 greenhouse gases. Making adjustments to 2007 World Energy Outlook projections to reflect more fully recent trends, we project annual emissions by 2030 to be almost double current volumes, 11 per cent higher than in the most pessimistic scenario developed by the Intergovernmental Panel on Climate Change (IPCC), and at a level reached only in 2050 in the business-as-usual scenario used by the Stern Review. This has major implications for the global approach to climate-change mitigation. The required effort is much larger than implicit in the IPCC data informing the current international climate negotiations. Large cuts in developed country emissions will be required, and significant deviations from baselines will be required in developing countries by 2020. It is hard to see how the required cuts could be achieved without all major developing as well as developed countries adopting economy-wide policies.
