The Last Glacial Maximum (LGM, ~ 21,000 years ago) is a major focus for evaluating how well climate models simulate climate changes as large as those expected in the future. Here we compare the latest climate models (CMIP6-PMIP4) to the previous one (CMIP5-PMIP3) and to reconstructions. Large-scale climate features (e.g. land-sea contrast, polar amplification) are well captured by all models, while regional changes (e.g. winter extratropical cooling, precipitations) are still poorly represented.
The Last Glacial Maximum (LGM, ~ 21,000 years ago) is a major focus for evaluating how well...
Review status: a revised version of this preprint is currently under review for the journal CP.
The PMIP4-CMIP6 Last Glacial Maximum experiments: preliminary results and comparison with the PMIP3-CMIP5 simulations
Masa Kageyama1,Sandy P. Harrison2,Marie-L. Kapsch3,Marcus Löfverström4,Juan M. Lora5,Uwe Mikolajewicz3,Sam Sherriff-Tadano6,Tristan Vadsaria6,Ayako Abe-Ouchi6,Nathaelle Bouttes1,Deepak Chandan7,Allegra N. LeGrande8,Fanny Lhardy1,Gerrit Lohmann9,Polina A. Morozova10,Rumi Ohgaito11,W. Richard Peltier7,Aurélien Quiquet1,Didier M. Roche1,12,Xiaoxu Shi9,Andreas Schmittner13,Jessica E. Tierney4,and Evgeny Volodin14Masa Kageyama et al.Masa Kageyama1,Sandy P. Harrison2,Marie-L. Kapsch3,Marcus Löfverström4,Juan M. Lora5,Uwe Mikolajewicz3,Sam Sherriff-Tadano6,Tristan Vadsaria6,Ayako Abe-Ouchi6,Nathaelle Bouttes1,Deepak Chandan7,Allegra N. LeGrande8,Fanny Lhardy1,Gerrit Lohmann9,Polina A. Morozova10,Rumi Ohgaito11,W. Richard Peltier7,Aurélien Quiquet1,Didier M. Roche1,12,Xiaoxu Shi9,Andreas Schmittner13,Jessica E. Tierney4,and Evgeny Volodin14
1Laboratoire des Sciences du Climat et de l’Environnement/Institut Pierre-Simon Laplace, UMR CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
2School of Archaeology, Geography and Environmental Science (SAGES), University of Reading, UK
3Max-Planck-Institut für Meteorologie, 20146 Hamburg, Germany
4University of Arizona, Tucson, AZ 85721, USA
5Yale University, New Haven, CT 06520, USA
6Atmospheric and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan
7Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S1A7, Canada
8NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025, USA
9Alfred Wegener Institute, Bremerhaven, Germany
10Institute of Geography, Russian Academy of Science, Moscow, Russia
11Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan
12Vrije Universiteit Amsterdam, Faculty of Science, Cluster Earth and Climate, de Boelelaan 1085, 1081HV Amsterdam, the Netherlands
13College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA
14Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russia
1Laboratoire des Sciences du Climat et de l’Environnement/Institut Pierre-Simon Laplace, UMR CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
2School of Archaeology, Geography and Environmental Science (SAGES), University of Reading, UK
3Max-Planck-Institut für Meteorologie, 20146 Hamburg, Germany
4University of Arizona, Tucson, AZ 85721, USA
5Yale University, New Haven, CT 06520, USA
6Atmospheric and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan
7Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S1A7, Canada
8NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025, USA
9Alfred Wegener Institute, Bremerhaven, Germany
10Institute of Geography, Russian Academy of Science, Moscow, Russia
11Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan
12Vrije Universiteit Amsterdam, Faculty of Science, Cluster Earth and Climate, de Boelelaan 1085, 1081HV Amsterdam, the Netherlands
13College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA
14Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russia
Received: 31 Dec 2019 – Accepted for review: 14 Jan 2020 – Discussion started: 23 Jan 2020
Abstract. The Last Glacial Maximum (LGM, ~ 21,000 years ago) has been a major focus for evaluating how well state-of-the-art climate models simulate climate changes as large as those expected in the future using paleoclimate reconstructions. A new generation of climate models have been used to generate LGM simulations as part of the Palaeoclimate Modelling Intercomparison Project (PMIP) contribution to the Coupled Model Intercomparison Project (CMIP). Here we provide a preliminary analysis and evaluation of the results of these LGM experiments (PMIP4-CMIP6) and compare them with the previous generation of simulations (PMIP3-CMIP5). We show that the PMIP4-CMIP6 are globally less cold and less dry than the PMIP3-CMIP5 simulations, most probably because of the use of a more realistic specification of the northern hemisphere ice sheets in the latest simulations although changes in model configuration may also contribute to this. There are important differences in both atmospheric and ocean circulation between the two sets of experiments, with the northern and southern jet streams being more poleward and the changes in the Atlantic Meridional Overturning Circulation being less pronounced in the PMIP4-CMIP6 simulations than in the PMIP3-CMIP5 simulations. Changes in simulated precipitation patterns are influenced by both temperature and circulation changes. Differences in simulated climate between individual models remain large so, although there are differences in the average behaviour across the two ensembles, the new simulation results are not fundamentally different from the PMIP3-CMIP5 results. Evaluation of large-scale climate features, such as land-sea contrast and polar amplification, confirms that the models capture these well and within the uncertainty of the palaeoclimate reconstructions. Nevertheless, regional climate changes are less well simulated: the models underestimate extratropical cooling, particularly in winter, and precipitation changes. The spatial patterns of increased precipitation associated with changes in the jet streams are also poorly captured. However, changes in the tropics are more realistic, particularly the changes in tropical temperatures over the oceans. Although these results are preliminary in nature, because of the limited number of LGM simulations currently available, they nevertheless point to the utility of using paleoclimate simulations to understand the mechanisms of climate change and evaluate model performance.
The Last Glacial Maximum (LGM, ~ 21,000 years ago) is a major focus for evaluating how well climate models simulate climate changes as large as those expected in the future. Here we compare the latest climate models (CMIP6-PMIP4) to the previous one (CMIP5-PMIP3) and to reconstructions. Large-scale climate features (e.g. land-sea contrast, polar amplification) are well captured by all models, while regional changes (e.g. winter extratropical cooling, precipitations) are still poorly represented.
The Last Glacial Maximum (LGM, ~ 21,000 years ago) is a major focus for evaluating how well...