Geoscience Reference
In-Depth Information
Figure 2: Climate sensitivity estimates from new research beginning in 2011
compared with the assessed range given in the IPCC Fifth Assessment Report (AR5)
and the collection of climate models used in the IPCC AR5
The 'likely' (greater than a 66 per cent likelihood of occurrence) range in the IPCC Assessment is indicated by the gray
bar. The arrows indicate the five to 95 per cent confidence bounds for each estimate along with the best estimate (median
of each probability density function; or the mean of multiple estimates; vertical line). Ring et al. present four estimates of
theclimate sensitivity andtheboxencompasses thoseestimates.
29
Theright-handsideoftheIPCCAR5rangeisactually
the90percentupperbound(theIPCCdoesnotactuallystatethevaluefortheupper95percentconfidenceboundoftheir
estimate). Spencer and Braswell produced a single sensitivity value that best-matched ocean heat content observations
and the internal ('natural') oscillations they observed.
30
Source: P.J. Michaels and P. C. Knappenberger, “More Evidence for a Low Climate Sensitivity”, available at
