A new approach allows the temperature forcing of CO2 and short-lived climate pollutants (SLCPs) to be examined under a common cumulative framework. While anthropogenic warming is largely determined by cumulative emissions of CO2, SLCPs—including soot, other aerosols and methane—also play a role. Quantifying their impact on global temperature is, however, distorted by existing methodologies using conventional Global Warming Potentials (GWP) to convert SLCPs to "CO2-equivalent" emissions.

A team of international scientists led by Professor Myles Allen, Director of the Oxford Martin Programme on Climate Pollutants, provide a solution. A modified form of GWP—GWP*, which relates cumulative CO2 emissions with contemporary SLCP emissions—is shown to better represent the future climate forcing of both long- and short-term pollutants. Use of GWP* could improve climate policy design, benefiting mitigation strategies to achieve the Paris Agreement targets.

In this video Dr Michelle Cain, discusses the motivation for the research, the use of the proposed metric, GWP*, and how it will enable people to assess emission reductions in relation to the long term temperature goal.

This video is based on work published in:

Allen, M. R., Shine, K. P., Fuglestvedt, J. S., Millar, R. J., Cain, M., Frame, D. J., & Macey, A. H. (2018). A solution to the misrepresentations of CO2-equivalent emissions of short-lived climate pollutants under ambitious mitigation. Npj Climate and Atmospheric Science, 1(1), 16. https://doi.org/10.1038/s41612-018-0026-8