Global emissions setting course for 5°C warming by 2100

It is now likely that in the longer term there will be a reliance on technologies that remove carbon dioxide from the atmosphere such as carbon capture and storage connected to bioenergy.

“We are effectively relying on technologies that are yet to be developed and this leads to persistent uncertainties on how much they can contribute to future mitigation” said lead author of the study Glen Peters of CICERO, a climate research institute in Norway.

The continued growth in carbon dioxide emissions reconfirms the temporary effect of the global financial crisis on emissions and may lock us into a high emissions pathway.

“There is considerable inertia in technical, social, and political systems, and even if an aggressive global agreement is reached at the negotiating table in Doha, it may take more than a decade before emissions begin to decrease”, said co-author Robbie Andrew of CICERO.

However, previous energy transitions in Belgium, Denmark, France, Sweden, and the UK have led to emission reductions as high as 5% per year over decade-long periods even without climate policy.

“Scaling up similar energy transitions across more countries, can kick-start global mitigation with negligible costs. To deepen and sustain these energy transitions in a broad range of countries requires aggressive policy drivers” said Peters.

“The continued economic troubles in the developed world have led to reduced emissions, but this is more than compensated by strong emissions growth in fast-growing economies such as China”, said Peters.

The study shows that global carbon emissions in 2011 were 54% above 1990 levels. Developed countries have largely stabilised their emissions below 1990 levels and most of the growth in global carbon dioxide emissions occurs in emerging economies.

Chinese emissions grew 10% in 2011, or over 800 million tonnes carbon¬ dioxide which is as much as Germany emits in one year. China is emitting as much as the European Union on a per capita basis, about 36% higher than the global average per capita emissions.

“Strong emissions growth in some developing countries continually changes the global distribution of emissions, and arguments on equity that existed in 1990 no longer apply in 2012”, said Peters.

In 1990 developing countries accounting for 35% percent of global carbon dioxide emissions, but in 2011 this was 58%.

“Each year of increased emissions makes a two degree target harder to achieve. The only feasible way to keep below two degrees is for global reductions in emissions and this can only happen if the top emitters in the developed and developing world have deep and sustained mitigation”, said Peters.

"I am worried that the risks of dangerous climate change are too high on our current emissions trajectory," said co-author Prof Corinne Le Quéré, Director of the Tyndall Centre for Climate Change Research and Professor at the University of East Anglia.

"We must reverse the trends in emissions before 2020, countries have done it in the past and we can do it worldwide. Everyone has a role."

This research is based on the release of an extensive new dataset by the Global Carbon Project, published simultaneously in Nature Climate Change and Earth System Science Data Discussions.

The Global Carbon Project is sponsored by IGBP.

The challenge to keep global warming below two degrees, by G. Peters, R. Andrew, T. Boden, J. Canadell, P. Ciais, C. Le Quéré, G. Marland, M. Raupach, C. Wilson is published online by Nature Climate Change.

http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate1783.html

“The Global Carbon Budget 1959–2011” by C. Le Quéré, R. Andres, T. Boden, T. Conway, R. Houghton, J. House, G. Marland, G. Peters, G. van der Werf, A. Ahlström, R. Andrew,  L. Bopp, J. Canadell, P. Ciais, S. Doney, P. Friedlingstein, C. Huntingford, A. Jain, C. Jourdain, E. Kato, R. Keeling, K. Goldewijk, S. Levis, P. Levy, M. Lomas, B. Poulter, M. Raupach, J. Schwinger, S. Sitch, B. Stocker, N. Viovy, S. Zaehle and N. Zeng, is published by Earth System Science Data Discussions,(from 2 Dec, 1800GMT). DOI: 10.5194/essdd-5-1107-2012. The paper is freely available.

“Global, Regional, and National Fossil-Fuel CO2 Emissions in Trends” by T. Boden, G. Marland, R. Andres is available from the Carbon Dioxide Information Analysis Center (CDIAC). DOI: 10.3334/CDIAC/GCP_V2012. The data is freely available.

Global Carbon Project “Carbon Budget 2012 Presentation”.