Earth system responses to external forcings : opportunities from paleoclimate studies and the Paleoclimate Modelling Intercomparison Project (PMIP) for CMIP

Paleoclimate information has played a key role in demonstrating how the Earth System responds to a variety of external forcings and how the earth’s climate is tightly related to atmospheric greenhouse gas concentrations. Although no strict analogue of possible future climate states exists, testing our understanding of the earth system, as embedded in earth system models, for conditions widely different from the historical period, is made possible by the existence of paleoclimate and paleoenvironmental reconstructions. Since its start in 1995, PMIP, the Paleoclimate Modelling Intercomparison Project (https://pmip.lsce.ipsl.fr/), has fostered and coordinated model-model and model-data comparisons for key periods: the mid-Holocene, ~6000 years ago, the Last Glacial Maximum (LGM), 21,000 years ago, the last two millennia, the last interglacial, the mid-Pliocene warm period (MPWP) were the key periods for PMIP4-CMIP6, with specific targets for each period. For instance, the enhanced monsoons and response of the northern high latitudes for the mid Holocene, the fate of Arctic sea ice and climate of the last interglacial, large spatial gradients and equilibrium climate sensitivity for the LGM and MPWP. In addition, each of these periods stood as reference for further PMIP experiments aimed to better understand the response of the climate system to external forcings.For the next CMIP phase, PMIP continues to contribute studies on the responses to external forcings. This poster will present the targets for the FastTrack last interglacial experiment (abrupt-127k) as well as future opportunities related to other periods (e. g. Kageyama et al., 2024). We look forward to discuss with the CMIP and PMIP communities to plan further cross-cutting work and analyses.Acknowledgements and cited reference.We are acknowledging the help of the PMIP community in building PMIP over the years.Kageyama M, et al., (2024) Lessons from paleoclimates for recent and future climate change: opportunities and insights. Front. Clim. 6:1511997. doi: 10.3389/fclim.2024.1511997