title: Making sense of palaeoclimate sensitivity.
abstract: Many palaeoclimate studies have quantified pre-anthropogenic climate change to calculate climate sensitivity (equilibrium temperature change in response to radiative forcing change), but a lack of consistent methodologies produces a wide range of estimates and hinders comparability of results. Here we present a stricter approach, to improve intercomparison of palaeoclimate sensitivity estimates in a manner compatible with equilibrium projections for future climate change. Over the past 65 million years, this reveals a climate sensitivity (in K W(-1) m(2)) of 0.3-1.9 or 0.6-1.3 at 95% or 68% probability, respectively. The latter implies a warming of 2.2-4.8 K per doubling of atmospheric CO(2), which agrees with IPCC estimates.
mesh_terms: D002138:Calibration; D002245:Carbon Dioxide / Q000032:analysis; D002980:Climate; D058735:Environmental Policy; D005246:Feedback; D057232:Global Warming / Q000266:history / Q000706:statistics & numerical data; D049690:History, Ancient; D008962:Models, Theoretical; D011336:Probability; D015203:Reproducibility of Results; D013696:Temperature; D013997:Time Factors
chemical_list: D002245:Carbon Dioxide