The PMIP4 Contribution to CMIP6-Part 4: Scientific Objectives and Experimental Design of the PMIP4-CMIP6 Last Glacial Maximum Experiments and PMIP4 Sensitivity Experiments

摘要: Abstract. The Last Glacial Maximum (LGM, 21 000 years ago) is one of the suite paleoclimate simulations included in current phase Coupled Model Intercomparison Project (CMIP6). It an interval when insolation was similar to present, but global ice volume at a maximum, eustatic sea level or close minimum, greenhouse gas concentrations were lower, atmospheric aerosol loadings higher than today, and vegetation land-surface characteristics different from today. LGM has been focus for Paleoclimate Modelling (PMIP) since its inception, thus many problems that might be associated with simulating such radically climate are well documented. state provides ideal case study evaluating model performance because changes forcing temperature between pre-industrial same order magnitude as those projected end 21st century. Thus, CMIP6 experiment could provide additional information can used constrain estimates sensitivity. design Tier 1 (lgm) includes assessment uncertainties boundary conditions, particular through use reconstructions sheets change dust forcing. Additional (Tier 2) sensitivity experiments have designed quantify feedbacks loadings, isolate role individual forcings. analysis evaluation will capitalize on relative abundance paleoenvironmental observations quantitative already available LGM.