Otto et al. 2013
Otto, A., F.E.L. Otto, O. Boucher, J. Church, G. Hegerl, P.M. Forster, N.P. Gillett, J. Gregory, G.C. Johnson, R. Knutti, N. Lewis, U. Lohmann, J. Marotzke, G. Myhre,, B. Stevens, and M.R. Allen, 2013: Energy budget constraints on climate response. Nature Geosci., 6, 415-416, doi:10.1038/ngeo1836.
The rate of global mean warming has been lower over the past decade than previously. It has been argued that this observation might require a downwards revision of estimates of equilibrium climate sensitivity, that is, the long-term (equilibrium) temperature response to a doubling of atmospheric CO2 concentrations. Using up-to-date data on radiative forcing, global mean surface temperature and total heat uptake in the Earth system, we find that the global energy budget implies a range of values for the equilibrium climate sensitivity that is in agreement with earlier estimates, within the limits of uncertainty. The energy budget of the most recent decade does, however, indicate a lower range of values for the more policy-relevant transient climate response (the temperature increase at the point of doubling of the atmospheric CO2 concentration following a linear ramp of increasing greenhouse gas forcing) than the range obtained by either analysing the energy budget of earlier decades or current climate model simulations.