Atmospheric stabilization and the timing of carbon mitigation
Stabilization of atmospheric CO2 concentrations below a pre-industrial doubling (~550 ppm) is a commonly cited target in climate policy assessment. When the rate at which future emissions can fall is assumed to be fixed, the peak atmospheric concentration – or the stabilization “frontier” – is an increasing and convex function of the length of postponement. Here we find that a decline in emissions of 1% year−1 beginning today would place the frontier near 475 ppm and that when mitigation is postponed, options disappear (on average) at the rate of ~9 ppm year−1, meaning that delays of more than a decade will likely preclude stabilization below a doubling. When constraints on the future decline rate of emissions are relaxed, a particular atmospheric target can be realized in many ways, with scenarios that allow longer postponement of emissions reductions requiring greater increases in the intensity of future mitigation. However, the marginal rate of substitution between future mitigation and present delay becomes prohibitively large when the balance is shifted too far toward the future, meaning that some amount of postponement cannot be fully offset by simply increasing the intensity of future mitigation. Consequently, these results suggest that a practical transition path to a given stabilization target in the most commonly cited range can allow, at most, one or two decades of delay.
Unable to display preview. Download preview PDF.
- Houghton JT et al (ed) (2001) Climate change 2001: the scientific basis. Cambridge University Press, Cambridge, UKGoogle Scholar
- Keeling CD, Whorf TP (2005) Atmospheric CO2 records from sites in the SIO air sampling network. In: Trends: a compendium of data on global change, carbon dioxide information Analysis Center. Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, TN. Digital data available at http://cdiac.ornl.gov/trends/co2/sio-mlo.htm
- Orr JC et al (2000) Abiotic how-to document. Text available at http://www.ipsl.jussieu.fr/OCMIP
- Siegenthaler U, Joos F (1992) Use of a simple model for studying ocean tracer distributions and the global carbon cycle. Tellus 44B:186–207Google Scholar
- United Nations Framework Convention on Climate Change (UNFCCC) (1992) Text available at http://www.unfccc.int
- Watson RT et al (2001) Climate change 2001: the synthesis report. Cambridge University Press, Cambridge, UKGoogle Scholar
- Webster M (2002) The curious role of learning in climate policy: should we wait for more data? Energy J 23:97–119Google Scholar
- Zeebe RE, Wolf-Gladrow D (2003) CO2 in seawater: equilibirum, kinetics, isotopes. Elsevier, AmsterdamGoogle Scholar