The indirect global warming potential and global temperature change potential due to methane oxidation

Methane is the second most important anthropogenic greenhouse gas in the atmosphere next to carbon dioxide. Its global warming potential (GWP) for a time horizon of 100 years is 25, which makes it an attractive target for climate mitigation policies. Although the methane GWP traditionally includes the methane indirect effects on the concentrations of ozone and stratospheric water vapour, it does not take into account the production of carbon dioxide from methane oxidation. We argue here that this CO2-induced effect should be included for fossil sources of methane, which results in slightly larger GWP values for all time horizons. If the global temperature change potential is used as an alternative climate metric, then the impact of the CO2-induced effect is proportionally much larger. We also discuss what the correction term should be for methane from anthropogenic biogenic sources.

[1]  David S. Lee,et al.  Transport impacts on atmosphere and climate: Metrics , 2010 .

[2]  M. Sanderson,et al.  Impact of increasing ship emissions on air quality and deposition over Europe by 2030 , 2009 .

[3]  R. Betts,et al.  Changes in Atmospheric Constituents and in Radiative Forcing. Chapter 2 , 2007 .

[4]  Jan S Fuglestvedt,et al.  Comparing the climate effect of emissions of short- and long-lived climate agents , 2007, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[5]  Bas Eickhout,et al.  Long-Term Multi-Gas Scenarios to Stabilise Radiative Forcing - Exploring Costs and Benefits Within an Integrated Assessment Framework , 2006 .

[6]  J. Fuglestvedt,et al.  Alternatives to the Global Warming Potential for Comparing Climate Impacts of Emissions of Greenhouse Gases , 2005 .

[7]  Alan S. Manne,et al.  An alternative approach to establishing trade-offs among greenhouse gases , 2001, Nature.

[8]  K. Shine.  Radiative Forcing of Climate Change , 2000 .

[9]  J. Hansen,et al.  Global warming in the twenty-first century: an alternative scenario. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[10]  A. Ridgwell,et al.  Consumption of atmospheric methane by soils: A process‐based model , 1999 .

[11]  F. Joos,et al.  Pulse response functions are cost-efficient tools to model the link between carbon emissions, atmospheric CO2 and global warming , 1996 .

[12]  Michael J. Prather,et al.  Lifetimes and eigenstates in atmospheric chemistry , 1994 .

[13]  Olivier Boucher,et al.  Climate trade-off between black carbon and carbon dioxide emissions , 2008 .

[14]  N. H. Ravindranath,et al.  2006 IPCC Guidelines for National Greenhouse Gas Inventories , 2006 .

[15]  Van Vuuren.  Long-term multigas scenarios to stabilise radiative forcing-Exploring costs and benefits within an integrated assessment framework. Multigas mitigation and climate policy , 2006 .

[16]  D. Schimel,et al.  Atmospheric Chemistry and Greenhouse Gases , 1999 .