@article{sablon25aa,
  author = {Sablon, L. and Maffre, P. and Goddéris, Y. and Valdes, P. J. and Gérard, J. and Huygh, J. J. C. and Da Silva, A. and Crucifix, M.},
  editor = {},
  year = {2025},
  title = {An Emulator-Based Modelling Framework for Studying Astronomical Controls on Ocean Anoxia with an Application on the Devonian},
  doi = {10.5194/egusphere-2025-1696},
  url = {http://dx.doi.org/10.5194/egusphere-2025-1696},
  publisher = {Copernicus GmbH},
  keywords = {preprint}
}

@article{mitsui24aa,
  author = {Mitsui, T. and Ditlevsen, P. and Boers, N. and Crucifix, M.},
  editor = {},
  year = {2024},
  title = {100-kyr ice age cycles as a timescale matching problem},
  doi = {10.5194/esd-2024-39},
  url = {http://dx.doi.org/10.5194/esd-2024-39},
  publisher = {Copernicus GmbH},
  keywords = {preprint}
}

@article{cp-21-239-2025,
  author = {G\'erard, J. and Sablon, L. and Huygh, J. J. C. and Da Silva, A.-C. and Pohl, A. and V\'erard, C. and Crucifix, M.},
  title = {Exploring the mechanisms of Devonian oceanic anoxia: impact of ocean dynamics, palaeogeography, and orbital forcing},
  journal = {Climate of the Past},
  volume = {21},
  year = {2025},
  number = {1},
  pages = {239--260},
  url = {https://cp.copernicus.org/articles/21/239/2025/},
  doi = {10.5194/cp-21-239-2025}
}

@article{gerard25aa,
  author = {G\'erard, J. and Sablon, L. and Huygh, J. J. C. and Da Silva, A.-C. and Pohl, A. and V\'erard, C. and Crucifix, M.},
  title = {Exploring the mechanisms of Devonian oceanic anoxia: impact of ocean dynamics, palaeogeography, and orbital forcing},
  journal = {Climate of the Past},
  volume = {21},
  year = {2025},
  number = {1},
  pages = {239--260},
  url = {https://cp.copernicus.org/articles/21/239/2025/},
  doi = {10.5194/cp-21-239-2025}
}

@article{karyu25aa,
  author = {Karyu, H. and Kuroda, T. and Mahieux, A. and Viscardy, S. and Määttänen, A. and Terada, N. and Robert, S. and Vandaele, A. C. and Crucifix, M.},
  editor = {},
  year = {2025},
  title = {A Microphysics Model of Multicomponent Venus’ Clouds With a High‐Accuracy Condensation Scheme},
  journal = {Earth and Space Science},
  volume = {12},
  doi = {10.1029/2025ea004203},
  url = {http://dx.doi.org/10.1029/2025EA004203},
  publisher = {American Geophysical Union (AGU)},
  number = {6},
  issn = {2333-5084},
  internal = {planetary}
}

@article{vanderveken25aa,
  author = {Vanderveken, L. and Crucifix, M.},
  editor = {},
  year = {2025},
  title = {Rate-induced transitions and noise-driven resilience in vegetation pattern dynamics},
  pages = {189–200},
  journal = {Nonlinear Processes in Geophysics},
  volume = {32},
  doi = {10.5194/npg-32-189-2025},
  url = {http://dx.doi.org/10.5194/npg-32-189-2025},
  publisher = {Copernicus GmbH},
  number = {2},
  issn = {1607-7946},
  internal = {vegetation-climate, non-linear}
}

@article{hamilton25aa,
  author = {Hamilton, O. and Demaeyer, J. and Crucifix, M. and Vannitsem, S.},
  editor = {},
  year = {2025},
  title = {Using unstable periodic orbits to understand blocking behavior in a low order landÔÇôatmosphere model},
  pages = {083126},
  journal = {Chaos: An Interdisciplinary Journal of Nonlinear Science},
  volume = {35},
  doi = {10.1063/5.0268852},
  url = {https://doi.org/10.1063/5.0268852},
  number = {8},
  issn = {1054-1500}
}

Unstable Periodic Orbits (UPOs) were used to identify regimes, and transitions between regimes, in a reduced-order coupled atmosphere-land spectral model. In this paper, we describe how the chaotic attractor of this model was clustered using the numerically derived set of UPOs. Using continuation software, the origin of these clusters was also investigated. The flow of model trajectories can be approximated using UPOs, a concept known as shadowing. Here, we extend that idea to look at the number of times a UPO shadows a model trajectory over a fixed time period, which we call cumulative shadowing. This concept was used to identify sets of UPOs that describe different life cycles of each cluster. The different regions of the attractor that were identified in the current work, and the transitions between these regions, are linked to specific atmospheric features known as atmospheric blocks.

@article{couplet25aa,
  author = {Couplet, V. and Martínez Montero, M. and Crucifix, M.},
  editor = {},
  year = {2025},
  title = {SURFER v3.0: a fast model with ice sheet tipping points and carbon cycle feedbacks for short- and long-term climate scenarios},
  pages = {3081–3129},
  journal = {Geoscientific Model Development},
  volume = {18},
  doi = {10.5194/gmd-18-3081-2025},
  url = {http://dx.doi.org/10.5194/gmd-18-3081-2025},
  publisher = {Copernicus GmbH},
  number = {10},
  issn = {1991-9603}
}

@article{gerard24aa,
  author = {Gérard, J. and Crucifix, M.},
  year = {2024},
  title = {Diagnosing the causes of AMOC slowdown in a coupled model: a cautionary tale},
  pages = {293–306},
  journal = {Earth System Dynamics},
  volume = {15},
  doi = {10.5194/esd-15-293-2024},
  url = {http://dx.doi.org/10.5194/esd-15-293-2024},
  publisher = {Copernicus GmbH},
  number = {2},
  issn = {2190-4987}
}

It is now established that the increase in atmospheric CO2 is likely to cause a weakening, or perhaps a collapse of the Atlantic Meridional Overturning Circulation (AMOC). To investigate the mechanisms of this response in CMIP5 models, Levang and Schmitt (2020) have estimated offline the geostrophic streamfunction in these models and decomposed the simulated changes into a contribution caused by the variations in temperature and salinity. They concluded that under a warming scenario, and for most models, the weakening of the AMOC is fundamentally driven by temperature anomalies while freshwater forcing actually acts to stabilize it. However, given that both 3-D fields of ocean temperature and salinity are expected to respond to a forcing at the ocean surface, it is unclear to what extent the diagnostic is informative about the nature of the forcing. To clarify this question, we used the Earth system Model of Intermediate Complexity (EMIC) cGENIE, which is equipped with the C-GOLDSTEIN friction-geostrophic model. First, we reproduced the experiments simulating the RCP8.5 warming scenario and observed that cGENIE behaves similarly to the majority of the CMIP5 models considered by Levang and Schmitt (2020), with the response dominated by the changes in the thermal structure of the ocean. Next, we considered hysteresis experiments associated with (1) water hosing and (2) CO2 increase and decrease. In all experiments, initial changes in the ocean streamfunction appear to be primarily caused by the changes in the temperature distribution, with variations in the 3-D distribution of salinity compensating only partly for the temperature contribution. These experiments also reveal limited sensitivity to changes in the ocean’s salinity inventory. That the diagnostics behave similarly in CO2 and freshwater forcing scenarios suggests that the output of the diagnostic proposed in Levang and Schmitt (2020) is mainly determined by the internal structure of the ocean circulation, rather than by the forcing applied to it. Our results illustrate the difficulty of inferring any information about the applied forcing from the thermal wind diagnostic and raise questions about the feasibility of designing a diagnostic or experiment that could identify which aspect of the forcing (thermal or haline) is driving the weakening of the AMOC.

@article{martinez-montero24aa,
  author = {Martínez Montero, M. and Brede, N. and Couplet, V. and Crucifix, M. and Botta, N. and Wieners, C.},
  editor = {},
  year = {2024},
  title = {Lost options commitment: how short-term policies affect long-term scope of action},
  journal = {Oxford Open Climate Change},
  volume = {4},
  doi = {10.1093/oxfclm/kgae004},
  url = {http://dx.doi.org/10.1093/oxfclm/kgae004},
  publisher = {Oxford University Press (OUP)},
  number = {1},
  issn = {2634-4068}
}

@article{benyami24aa,
  author = {Ben‐Yami, M. and Good, P. and Jackson, L. C. and Crucifix, M. and Hu, A. and Saenko, O. and Swingedouw, D. and Boers, N.},
  editor = {},
  year = {2024},
  title = {Impacts of AMOC Collapse on Monsoon Rainfall: A Multi‐Model Comparison},
  journal = {Earth’s Future},
  volume = {12},
  doi = {10.1029/2023ef003959},
  url = {http://dx.doi.org/10.1029/2023EF003959},
  publisher = {American Geophysical Union (AGU)},
  number = {9},
  issn = {2328-4277}
}

@article{vanderveken23aa,
  author = {Vanderveken, L. and Martínez Montero, M. and Crucifix, M.},
  editor = {},
  year = {2023},
  title = {Existence and influence of mixed states in a model of vegetation patterns},
  pages = {585–599},
  journal = {Nonlinear Processes in Geophysics},
  volume = {30},
  doi = {10.5194/npg-30-585-2023},
  url = {http://dx.doi.org/10.5194/npg-30-585-2023},
  publisher = {Copernicus GmbH},
  number = {4},
  issn = {1607-7946}
}

@article{hamilton23aa,
  author = {Hamilton, O. and Demaeyer, J. and Vannitsem, S. and Crucifix, M.},
  editor = {},
  year = {2023},
  title = {Multistability in a coupled ocean–atmosphere reduced‐order model: Nonlinear temperature equations},
  pages = {3423–3439},
  journal = {Quarterly Journal of the Royal Meteorological Society},
  volume = {149},
  doi = {10.1002/qj.4564},
  url = {http://dx.doi.org/10.1002/qj.4564},
  publisher = {Wiley},
  number = {757},
  issn = {1477-870X}
}

@article{verbitsky23aa,
  author = {Verbitsky, M. Y. and Crucifix, M.},
  editor = {},
  year = {2023},
  title = {Do phenomenological dynamical paleoclimate models have physical similarity with Nature? Seemingly, not all of them do},
  pages = {1793–1803},
  journal = {Climate of the Past},
  volume = {19},
  doi = {10.5194/cp-19-1793-2023},
  url = {http://dx.doi.org/10.5194/cp-19-1793-2023},
  publisher = {Copernicus GmbH},
  number = {9},
  issn = {1814-9332}
}

@article{wood23aa,
  author = {Wood, R. A. and Crucifix, M. and Lenton, T. M. and Mach, K. J. and Moore, C. and New, M. and Sharpe, S. and Stocker, T. F. and Sutton, R. T.},
  editor = {},
  year = {2023},
  title = {A Climate Science Toolkit for High Impact‐Low Likelihood Climate Risks},
  journal = {Earth’s Future},
  volume = {11},
  doi = {10.1029/2022ef003369},
  url = {http://dx.doi.org/10.1029/2022EF003369},
  publisher = {American Geophysical Union (AGU)},
  number = {4},
  issn = {2328-4277}
}

@article{van-breedam23aa,
  author = {Van Breedam, J. and Huybrechts, P. and Crucifix, M.},
  editor = {},
  year = {2023},
  title = {Hysteresis and orbital pacing of the early Cenozoic Antarctic ice sheet},
  pages = {2551–2568},
  journal = {Climate of the Past},
  volume = {19},
  doi = {10.5194/cp-19-2551-2023},
  url = {http://dx.doi.org/10.5194/cp-19-2551-2023},
  publisher = {Copernicus GmbH},
  number = {12},
  issn = {1814-9332}
}

@article{botta23aa,
  author = {Botta, N. and Brede, N. and Crucifix, M. and Ionescu, C. and Jansson, P. and Li, Z. and Martínez, M. and Richter, T.},
  editor = {},
  year = {2023},
  title = {Responsibility Under Uncertainty: Which Climate Decisions Matter Most?},
  pages = {337–365},
  journal = {Environmental Modeling & Assessment},
  volume = {28},
  doi = {10.1007/s10666-022-09867-w},
  url = {http://dx.doi.org/10.1007/s10666-022-09867-w},
  publisher = {Springer Science and Business Media LLC},
  number = {3},
  issn = {1573-2967}
}

@article{wouters22aa,
  author = {Wouters, S. and Crucifix, M. and Sinnesael, M. and Da Silva, A. and Zeeden, C. and Zivanovic, M. and Boulvain, F. and Devleeschouwer, X.},
  editor = {},
  year = {2022},
  title = {A decomposition approach to cyclostratigraphic signal processing},
  pages = {103894},
  journal = {Earth-Science Reviews},
  volume = {225},
  doi = {10.1016/j.earscirev.2021.103894},
  url = {http://dx.doi.org/10.1016/j.earscirev.2021.103894},
  publisher = {Elsevier BV},
  issn = {0012-8252}
}

@article{martinez-montero22aa,
  author = {Martínez Montero, M. and Crucifix, M. and Couplet, V. and Brede, N. and Botta, N.},
  editor = {},
  year = {2022},
  title = {SURFER v2.0: a flexible and simple model linking anthropogenic CO2 emissions and solar radiation modification to ocean acidification and sea level rise},
  pages = {8059–8084},
  journal = {Geoscientific Model Development},
  volume = {15},
  doi = {10.5194/gmd-15-8059-2022},
  url = {http://dx.doi.org/10.5194/gmd-15-8059-2022},
  publisher = {Copernicus GmbH},
  number = {21},
  issn = {1991-9603}
}

@article{van-breedam22aa,
  author = {Van Breedam, J. and Huybrechts, P. and Crucifix, M.},
  editor = {},
  year = {2022},
  title = {Modelling evidence for late Eocene Antarctic glaciations},
  pages = {117532},
  journal = {Earth and Planetary Science Letters},
  volume = {586},
  doi = {10.1016/j.epsl.2022.117532},
  url = {http://dx.doi.org/10.1016/j.epsl.2022.117532},
  publisher = {Elsevier BV},
  issn = {0012-821X}
}

@article{heydt21aa,
  author = {von der Heydt, A. S. and Ashwin, P. and Camp, C. D. and Crucifix, M. and Dijkstra, H. A. and Ditlevsen, P. and Lenton, T. M.},
  editor = {},
  year = {2021},
  title = {Quantification and interpretation of the climate variability record},
  pages = {103399},
  journal = {Global and Planetary Change},
  volume = {197},
  doi = {10.1016/j.gloplacha.2020.103399},
  url = {http://dx.doi.org/10.1016/j.gloplacha.2020.103399},
  publisher = {Elsevier BV},
  issn = {0921-8181}
}

@article{lenton21aa,
  author = {Lenton, T. M. and Kohler, T. A. and Marquet, P. A. and Boyle, R. A. and Crucifix, M. and Wilkinson, D. M. and Scheffer, M.},
  editor = {},
  year = {2021},
  title = {Survival of the Systems},
  journal = {Trends in Ecology & Evolution},
  doi = {10.1016/j.tree.2020.12.003},
  url = {http://dx.doi.org/10.1016/j.tree.2020.12.003},
  publisher = {Elsevier BV},
  issn = {0169-5347}
}

@article{verbitsky21aa,
  author = {Verbitsky, M. Y. and Crucifix, M.},
  editor = {},
  year = {2021},
  title = {ESD Ideas: The Peclet number is a cornerstone of the orbital and millennial Pleistocene variability},
  pages = {63--67},
  journal = {Earth System Dynamics},
  volume = {12},
  doi = {10.5194/esd-12-63-2021},
  url = {https://esd.copernicus.org/articles/12/63/2021/},
  number = {1}
}

@article{lyu21aa,
  author = {Lyu, A. Q. and Yin, Q. Z. and Crucifix, M. and Sun, Y. B.},
  editor = {},
  year = {2021},
  title = {Diverse Regional Sensitivity of Summer Precipitation in East Asia to Ice Volume, CO 2 and Astronomical Forcing},
  journal = {Geophysical Research Letters},
  volume = {48},
  doi = {10.1029/2020gl092005},
  url = {http://dx.doi.org/10.1029/2020GL092005},
  publisher = {American Geophysical Union (AGU)},
  number = {7},
  issn = {1944-8007}
}

@article{brovkin21aa,
  author = {Brovkin, V. and Brook, E. and Williams, J. W. and Bathiany, S. and Lenton, T. M. and Barton, M. and DeConto, R. M. and Donges, J. F. and Ganopolski, A. and McManus, J. and Praetorius, S. and de Vernal, A. and Abe-Ouchi, A. and Cheng, H. and Claussen, M. and Crucifix, M. and Gallopín, G. and Iglesias, V. and Kaufman, D. S. and Kleinen, T. and Lambert, F. and van der Leeuw, S. and Liddy, H. and Loutre, M. and McGee, D. and Rehfeld, K. and Rhodes, R. and Seddon, A. W. R. and Trauth, M. H. and Vanderveken, L. and Yu, Z.},
  editor = {},
  year = {2021},
  title = {Past abrupt changes, tipping points and cascading impacts in the Earth system},
  pages = {550–558},
  journal = {Nature Geoscience},
  volume = {14},
  doi = {10.1038/s41561-021-00790-5},
  url = {http://dx.doi.org/10.1038/s41561-021-00790-5},
  publisher = {Springer Science and Business Media LLC},
  number = {8},
  issn = {1752-0908}
}

@article{jebeile21aa,
  author = {Jebeile, J. and Crucifix, M.},
  editor = {},
  year = {2021},
  title = {Value management and model pluralism in climate science},
  pages = {120–127},
  journal = {Studies in History and Philosophy of Science},
  volume = {88},
  doi = {10.1016/j.shpsa.2021.06.004},
  url = {http://dx.doi.org/10.1016/j.shpsa.2021.06.004},
  publisher = {Elsevier BV},
  issn = {0039-3681}
}

@article{verbitsky20aa,
  author = {Verbitsky, M. Y. and Crucifix, M.},
  editor = {},
  year = {2020},
  title = {Pi-theorem generalization of the ice-age theory},
  pages = {281–289},
  journal = {Earth System Dynamics},
  volume = {11},
  doi = {10.5194/esd-11-281-2020},
  url = {http://dx.doi.org/10.5194/esd-11-281-2020},
  publisher = {Copernicus GmbH},
  number = {1},
  issn = {2190-4987}
}

@article{alexandrov20aa,
  author = {Alexandrov, D. V. and Bashkirtseva, I. A. and Ryashko, L. B. and Crucifix, M.},
  editor = {},
  year = {2020},
  title = {Nonlinear climate dynamics: From deterministic behavior to stochastic excitability and chaos},
  journal = {Physics Reports},
  doi = {10.1016/j.physrep.2020.11.002},
  url = {http://dx.doi.org/10.1016/j.physrep.2020.11.002},
  publisher = {Elsevier BV},
  issn = {0370-1573}
}

@article{jebeile20aa,
  author = {Jebeile, J. and Crucifix, M.},
  editor = {},
  year = {2020},
  title = {Multi-model ensembles in climate science: Mathematical structures and expert judgements},
  pages = {44–52},
  journal = {Studies in History and Philosophy of Science Part A},
  volume = {83},
  doi = {10.1016/j.shpsa.2020.03.001},
  url = {http://dx.doi.org/10.1016/j.shpsa.2020.03.001},
  publisher = {Elsevier BV},
  issn = {0039-3681}
}

@article{carson19aa,
  author = {Carson, J. and Crucifix, M. and Preston, S. P. and Wilkinson, R. D.},
  editor = {},
  year = {2019},
  title = {Quantifying age and model uncertainties in palaeoclimate data and dynamical climate models with a joint inferential analysis},
  pages = {20180854},
  journal = {Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences},
  volume = {475},
  doi = {10.1098/rspa.2018.0854},
  url = {http://dx.doi.org/10.1098/rspa.2018.0854},
  publisher = {The Royal Society},
  number = {2224},
  issn = {1471-2946}
}

@article{verbitsky19aa,
  author = {Verbitsky, M. Y. and Crucifix, M. and Volobuev, D. M.},
  editor = {},
  year = {2019},
  title = {ESD Ideas: Propagation of high-frequency forcing to ice age dynamics},
  pages = {257–260},
  journal = {Earth System Dynamics},
  volume = {10},
  doi = {10.5194/esd-10-257-2019},
  url = {http://dx.doi.org/10.5194/esd-10-257-2019},
  publisher = {Copernicus GmbH},
  number = {2},
  issn = {2190-4987}
}

@article{sun19aa,
  author = {Sun, Y. and Yin, Q. and Crucifix, M. and Clemens, S. C. and Araya-Melo, P. and Liu, W. and Qiang, X. and Liu, Q. and Zhao, H. and Liang, L. and Chen, H. and Li, Y. and Zhang, L. and Dong, G. and Li, M. and Zhou, W. and Berger, A. and An, Z.},
  editor = {},
  year = {2019},
  title = {Diverse manifestations of the mid-Pleistocene climate transition},
  journal = {Nature Communications},
  volume = {10},
  doi = {10.1038/s41467-018-08257-9},
  url = {https://doi.org/10.1038/s41467-018-08257-9},
  publisher = {Springer Science and Business Media {LLC}},
  number = {1}
}

@article{carson17aa,
  author = {Carson, J. and Crucifix, M. and Preston, S. and Wilkinson, R. D.},
  editor = {},
  year = {2018},
  title = {Bayesian model selection for the glacial-interglacial cycle},
  journal = {Journal of the Royal Statistical Society: Series C (Applied Statistics)},
  doi = {10.1111/rssc.12222},
  url = {http://dx.doi.org/10.1111/rssc.12222},
  publisher = {Wiley-Blackwell},
  issn = {0035-9254},
  volume = {67},
  pages = {25-54}
}

@article{mitsui18aa,
  author = {Mitsui, T. and Lenoir, G. and Crucifix, M.},
  editor = {},
  year = {2018},
  title = {Why glacial climates look multifractal},
  pages = {0},
  journal = {Dynamics and Statistics of the Climate System},
  volume = {in press}
}

@article{lenoir18aa,
  author = {Lenoir, G. and Crucifix, M.},
  editor = {},
  year = {2018},
  title = {A general theory on frequency and time–frequency analysis of irregularly sampled time series based on projection methods – Part 1: Frequency analysis},
  pages = {145–173},
  journal = {Nonlinear Processes in Geophysics},
  volume = {25},
  doi = {10.5194/npg-25-145-2018},
  url = {http://dx.doi.org/10.5194/npg-25-145-2018},
  publisher = {Copernicus GmbH},
  number = {1},
  issn = {1607-7946}
}

@article{lenoir18ab,
  author = {Lenoir, G. and Crucifix, M.},
  editor = {},
  year = {2018},
  title = {A general theory on frequency and time–frequency analysis of irregularly sampled time series based on projection methods – Part 2: Extension to time–frequency analysis},
  pages = {175–200},
  journal = {Nonlinear Processes in Geophysics},
  volume = {25},
  doi = {10.5194/npg-25-175-2018},
  url = {http://dx.doi.org/10.5194/npg-25-175-2018},
  publisher = {Copernicus GmbH},
  number = {1},
  issn = {1607-7946}
}

@article{steffen18aa,
  author = {Steffen, W. and Rockström, J. and Richardson, K. and Lenton, T. M. and Folke, C. and Liverman, D. and Summerhayes, C. P. and Barnosky, A. D. and Cornell, S. E. and Crucifix, M. and Donger, J. F. and Fetzer, I. and Lade, S. J. and Scheffer, M. and Winkelmann, R. and Schellnhuber, H. J.},
  editor = {},
  year = {2018},
  title = {Trajectories of the Earth System in the Anthropocene},
  pages = {201810141},
  journal = {Proceedings of the National Academy of Sciences},
  doi = {10.1073/pnas.1810141115},
  url = {http://dx.doi.org/10.1073/pnas.1810141115},
  publisher = {Proceedings of the National Academy of Sciences},
  issn = {1091-6490}
}

@article{verbitsky18aa,
  author = {Verbitsky, M. Y. and Crucifix, M. and Volobuev, D. M.},
  editor = {},
  year = {2018},
  title = {A theory of Pleistocene glacial rhythmicity},
  pages = {1025–1043},
  journal = {Earth System Dynamics},
  volume = {9},
  doi = {10.5194/esd-9-1025-2018},
  url = {http://dx.doi.org/10.5194/esd-9-1025-2018},
  publisher = {Copernicus GmbH},
  number = {3},
  issn = {2190-4987}
}

@article{rougier18aa,
  author = {Rougier, J. and Crucifix, M.},
  editor = {},
  year = {2018},
  title = {Uncertainty in Climate Science and Climate Policy},
  pages = {361–380},
  journal = {Climate Modelling},
  doi = {10.1007/978-3-319-65058-6_12},
  url = {http://dx.doi.org/10.1007/978-3-319-65058-6_12},
  publisher = {Springer International Publishing},
  isbn = {9783319650586}
}

@article{mitsui18ab,
  author = {Mitsui, T. and Lenoir, G. and Crucifix, M.},
  editor = {},
  year = {2018},
  title = {Is the glacial climate scale invariant?},
  journal = {Dynamics and Statistics of the Climate System},
  volume = {3},
  doi = {10.1093/climsys/dzy011},
  url = {http://dx.doi.org/10.1093/climsys/dzy011},
  publisher = {Oxford University Press (OUP)},
  number = {1},
  issn = {2059-6987}
}

@article{tzedakis17aa,
  author = {Tzedakis, P. C. and Crucifix, M. and Mitsui, T. and Wolff, E. W.},
  editor = {},
  year = {2017},
  title = {A simple rule to determine which insolation cycles lead to interglacials},
  pages = {427–432},
  journal = {Nature},
  volume = {542},
  doi = {10.1038/nature21364},
  url = {http://dx.doi.org/10.1038/nature21364},
  publisher = {Springer Nature},
  issn = {1476-4687}
}

@article{de-vleeschouwer17aa,
  author = {De Vleeschouwer, D. and Vahlenkamp, M. and Crucifix, M. and Pälike, H.},
  editor = {},
  year = {2017},
  title = {Alternating Southern and Northern Hemisphere climate response to astronomical forcing during the past 35 m.y.},
  pages = {375–378},
  journal = {Geology},
  volume = {45},
  doi = {10.1130/g38663.1},
  url = {http://dx.doi.org/10.1130/G38663.1},
  publisher = {Geological Society of America},
  number = {4},
  issn = {1943-2682}
}

@article{mitsui16ah,
  author = {Mitsui, T. and Crucifix, M.},
  editor = {},
  year = {2017},
  title = {Influence of external forcings on abrupt millennial-scale climate changes: a statistical modelling study},
  pages = {2729–2749},
  journal = {Climate Dynamics},
  volume = {48},
  doi = {10.1007/s00382-016-3235-z},
  url = {http://dx.doi.org/10.1007/s00382-016-3235-z},
  publisher = {Springer Nature},
  number = {7-8},
  issn = {1432-0894}
}

@article{valdes17aa,
  author = {Valdes, P. J. and Armstrong, E. and Badger, M. P. S. and Bradshaw, C. D. and Bragg, F. and Crucifix, M. and Davies-Barnard, T. and Day, J. J. and Farnsworth, A. and Gordon, C. and et al.},
  editor = {},
  year = {2017},
  title = {The BRIDGE HadCM3 family of climate models: HadCM3@Bristol v1.0},
  pages = {3715–3743},
  journal = {Geoscientific Model Development},
  volume = {10},
  doi = {10.5194/gmd-10-3715-2017},
  url = {http://dx.doi.org/10.5194/gmd-10-3715-2017},
  publisher = {Copernicus GmbH},
  number = {10},
  issn = {1991-9603}
}

@article{lord17aa,
  author = {Lord, N. S. and Crucifix, M. and Lunt, D. J. and Thorne, M. C. and Bounceur, N. and Dowsett, H. and O’Brien, C. L. and Ridgwell, A.},
  editor = {},
  year = {2017},
  title = {Emulation of long-term changes in global climate: application to the late Pliocene and future},
  pages = {1539–1571},
  journal = {Climate of the Past},
  volume = {13},
  doi = {10.5194/cp-13-1539-2017},
  url = {http://dx.doi.org/10.5194/cp-13-1539-2017},
  publisher = {Copernicus GmbH},
  number = {11},
  issn = {1814-9332}
}

@article{Crucifix_2016,
  author = {Crucifix, M.},
  editor = {},
  year = {2016},
  pages = {162--163},
  volume = {529},
  doi = {10.1038/529162a},
  url = {http://dx.doi.org/10.1038/529162a},
  issn = {1476-4687},
  title = {Climate science: Earth's narrow escape from a big freeze},
  journal = {Nature},
  number = {7585}
}

@article{heydt16aa,
  author = {von der Heydt, A. S. and Dijkstra, H. A. and van de Wal, R. S. W. and Caballero, R. and Crucifix, M. and Foster, G. L. and Huber, M. and Köhler, P. and Rohling, E. and Valdes, P. J. and Ashwin, P. and Bathiany, S. and Berends, T. and van Bree, L. G. J. and Ditlevsen, P. and Ghil, M. and Haywood, A. and Katzav, J. and Lohmann, G. and Lohmann, J. and Lucarini, V. and Marzocchi, A. and Pälike, H. and Ruvalcaba Baroni, I. and Simon, D. and Sluijs, A. and Stap, L. B. and Tantet, A. and Viebahn, J. and Ziegler, M.},
  editor = {},
  year = {2016},
  title = {Lessons on Climate Sensitivity From Past Climate Changes},
  journal = {Current Climate Change Reports},
  doi = {10.1007/s40641-016-0049-3},
  url = {http://dx.doi.org/10.1007/s40641-016-0049-3},
  publisher = {Springer Nature},
  issn = {2198-6061}
}

@article{Bathiany16aa,
  author = {Bathiany, S. and Dijkstra, H. and Crucifix, M. and Dakos, V. and Brovkin, V. and Williamson, M. and Lenton, T. and Scheffer, M.},
  editor = {},
  year = {2016},
  title = {Beyond bifurcation -- using complex models to understand and predict abrupt climate change},
  journal = {Dynamics and Statistics of the Climate System},
  doi = {10.1093/climsys/dzw004},
  publisher = {The Oxford University Press},
  volume = {1}
}

@article{Berger15aa,
  author = {Berger, A. and Crucifix, M. and Hodell, D. A. and Mangili, C. and McManus, J. F. and Otto-Bliesner, B. and Pol, K. and Raynaud, D. and Skinner, L. C. and Tzedakis, P. C. and Wolff, E. W. and Yin, Q. Z. and Abe-Ouchi, A. and Barbante, C. and Brovkin, V. and Cacho, I. and Capron, E. and Ferretti, P. and Ganopolski, A. and Grimalt, J. O. and Hönisch, B. and Kawamura, K. and Landais, A. and Margari, V. and Martrat, B. and Masson-Delmotte, V. and Mokeddem, Z. and Parrenin, F. and Prokopenko, A. A. and Rashid, H. and Schulz, M. and Vazquez Riveiros, N.},
  editor = {},
  year = {2015},
  journal = {Reviews of Geophysics}
}

@article{Carson15aa,
  author = {Carson, J. and Crucifix, M. and Preston, S. and Wilkinson, R. D.},
  editor = {},
  year = {2015},
  arxiv = {1511.03467},
  title = {Bayesian model selection for the glacial-interglacial cycle},
  journal = {ArXiv e-prints}
}

@article{Mitsui15ag,
  author = {Mitsui, T. and Crucifix, M.},
  editor = {},
  year = {2015},
  journal = {submitted},
  arxiv = {1510.06290},
  title = {A statistical modelling study of the abrupt millennial-scale climate changes focusing on the influence of external forcings}
}

@article{Regoli15aa,
  author = {Regoli, F. and de Garidel-Thoron, T. and Tachikawa, K. and Jian, Z. and Ye, L. and Droxler, A. W. and Lenoir, G. and Crucifix, M. and Barbarin, N. and Beaufort, L.},
  editor = {},
  year = {2015},
  pages = {439--455},
  doi = {10.1002/2014pa002696},
  url = {http://dx.doi.org/10.1002/2014PA002696},
  title = {Progressive shoaling of the equatorial Pacific thermocline over the last eight glacial periods},
  volume = {30},
  journal = {Paleoceanography},
  number = {5}
}

@article{Mitsui15ad,
  author = {Mitsui, T. and Crucifix, M. and Aihara, K.},
  editor = {},
  year = {2015},
  pages = {25 - 33},
  journal = {Physica D: Nonlinear Phenomena},
  volume = {306},
  doi = {10.1016/j.physd.2015.05.007},
  arxiv = {1506.04628},
  issn = {0167-2789},
  keywords = {Middle-Pleistocene transition},
  title = {Bifurcations and strange nonchaotic attractors in a phase oscillator model of glacial--interglacial cycles}
}

Abstract Glacial–interglacial cycles are large variations in continental ice mass and greenhouse gases, which have dominated climate variability over the Quaternary. The dominant periodicity of the cycles is ∼ 40 kyr before the so-called middle Pleistocene transition between ∼ 1.2 and ∼ 0.7 Myr ago, and it is ∼ 100 kyr after the transition. In this paper, the dynamics of glacial–interglacial cycles are investigated using a phase oscillator model forced by the time-varying incoming solar radiation (insolation). We analyze the bifurcations of the system and show that strange nonchaotic attractors appear through nonsmooth saddle–node bifurcations of tori. The bifurcation analysis indicates that mode-locking is likely to occur for the 41 kyr glacial cycles but not likely for the 100 kyr glacial cycles. The sequence of mode-locked 41 kyr cycles is robust to small parameter changes. However, the sequence of 100 kyr glacial cycles can be sensitive to parameter changes when the system has a strange nonchaotic attractor.

@article{Bounceur15aa,
  author = {Bounceur, N. and Crucifix, M. and Wilkinson, R. D.},
  editor = {},
  year = {2015},
  pages = {205--224},
  journal = {Earth System Dynamics},
  doi = {10.5194/esd-6-205-2015},
  url = {http://www.earth-syst-dynam.net/6/205/2015/},
  title = {Global sensitivity analysis of the climate-vegetation system to astronomical forcing: an emulator-based approach},
  volume = {6},
  number = {1}
}

@article{Araya-Melo15aa,
  author = {Araya-Melo, P. A. and Crucifix, M. and Bounceur, N.},
  editor = {},
  year = {2015},
  pages = {45--61},
  doi = {10.5194/cp-11-45-2015},
  url = {http://www.clim-past.net/11/45/2015/},
  title = {Global sensitivity analysis of the Indian monsoon during the Pleistocene},
  volume = {11},
  journal = {Climate of the Past},
  number = {1}
}

@article{Yin14aa,
  author = {Yin, Q. Z. and Singh, U. K. and Berger, A. and Guo, Z. T. and Crucifix, M.},
  editor = {},
  year = {2014},
  pages = {1645--1657},
  doi = {10.5194/cp-10-1645-2014},
  url = {http://www.clim-past.net/10/1645/2014/},
  title = {Relative impact of insolation and the Indo-Pacific warm pool surface temperature on the East Asia summer monsoon during the MIS-13 interglacial},
  volume = {10},
  journal = {Climate of the Past},
  number = {5}
}

@article{tc-8-1347-2014,
  author = {Maris, M. N. A. and de Boer, B. and Ligtenberg, S. R. M. and Crucifix, M. and van de Berg, W. J. and Oerlemans, J.},
  editor = {},
  year = {2014},
  pages = {1347--1360},
  journal = {The Cryosphere},
  volume = {8},
  doi = {10.5194/tc-8-1347-2014},
  url = {http://www.the-cryosphere.net/8/1347/2014/},
  title = {Modelling the evolution of the Antarctic ice sheet since the last interglacial},
  number = {4}
}

@article{Bounceur14ab,
  author = {Bounceur, N. and Crucifix, M. and Wilkinson, R. D.},
  editor = {},
  year = {2014},
  pages = {901--943},
  doi = {10.5194/esdd-5-901-2014},
  url = {http://www.earth-syst-dynam-discuss.net/5/901/2014/},
  volume = {5},
  journal = {Earth System Dynamics Discussions},
  number = {2}
}

(updated) A global sensitivity analysis is performed to describe the effects of astronomical forcing on the climate- vegetation system simulated by the model of intermediate complexity LOVECLIM in interglacial conditions. The methodology relies on the estimation of sensitivity measures, using a Gaussian process emulator as a fast surrogate of the climate model, calibrated on a set of well chosen experiments. The outputs considered here are the annual mean temperature and precipitation and the Growing Degree Days (GDD). The experiments were run on two distinct land surface schemes to estimate the importance of vegetation feedbacks on climate variance. This analysis provides a spatial description of the variance due to the factors and their combinations, in the form of “fingerprints" obtained from the covariance indices. The results are broadly consistent with the current understanding of Earth’s climate response to the astronomical forcing. In particular, precession and obliquity are found to contribute equally to (GDD) in the northern hemisphere, and the effects of obliquity on the response of southern hemisphere temperature dominate precession effects. Precession dominates precipitation changes in subtropical areas. Compared to standard approaches based on a small number of simulations for well-defined past epochs, the methodology presented here allows us to identify more systematically regions susceptible of experiencing rapid climate change in response to the smooth astronomical forcing change. In particular, we find that using interactive vegetation significantly enhances the expected rates of climate change, specifically in the Sahel (up to 50 % precipitation change in 1,000 years) and in the Canadian Arctic region (up to 3 degrees in 1000 years). None of the tested astronomical configurations were found to induce multiple steady states, but we observe, at low obliquity, the development of an oscillatory pattern that has already been reported in LOVECLIM. Although the mathematics of the analysis are fairly straightforward, the emulation approach still requires considerable care in its implementation. We discuss the effects of the choice of length scales, the type of emulator and estimate uncertainties associated with specific computational aspects, to conclude that the PC emulator is a reasonable option for this kind of application.

@article{Crucifix14ae,
  author = {Crucifix, M. and Zorita, E. and Peterschmitt, J. Y.},
  editor = {},
  year = {2014},
  pages = {47},
  journal = {PAGES Magazine},
  title = {Third general meeting of PMIP3},
  volume = {22},
  number = {2}
}

@article{De-Vleeschouwer14ab,
  author = {De Vleeschouwer, D. and Crucifix, M. and Bounceur, N. and Claeys, P.},
  editor = {},
  year = {2014},
  pages = {65--80},
  volume = {120},
  doi = {10.1016/j.gloplacha.2014.06.002},
  date = {2014/9//},
  url = {http://www.sciencedirect.com/science/article/pii/S092181811400109X},
  keywords = {Late Devonian; Astronomical forcing; General circulation model; HadSM3; Precession; Obliquity},
  title = {The impact of astronomical forcing on the Late Devonian greenhouse climate},
  journal = {Global and Planetary Change},
  number = {0}
}

Abstract The geological record of the Paleozoic often exhibits cyclic features, in many cases the result of changes in paleoclimate. However, a thorough understanding of the processes that were driving Paleozoic climate change has not yet been reached. The main reason is relatively poor time-control on Paleozoic paleoclimate proxy records. This problem can be overcome by the identification of cyclic features resulting from astronomical climate forcing in the stratigraphic record. To correctly identify these cyclic features, it is necessary to quantify the effects of astronomical climate forcing under conditions different from today. In this work, we apply Late Devonian (375 Ma) boundary conditions to the Hadley Centre general circulation model (HadSM3). We estimate the response of Late Devonian climate to astronomical forcing by keeping all other forcing factors (e.g. paleogeography, pCO2, vegetation distribution) fixed. Thirty-one different “snapshots” of Late Devonian climate are simulated, by running the model with different combinations of eccentricity (e), obliquity (ε) and precession ( ω ˜ ). From the comparison of these 31 simulations, it appears that feedback mechanisms play an important role in the conversion of astronomically driven insolation variations into climate change, such as the formation of sea-ice and the development of an extensive snow cover on Gondwana. We compare the “median orbit” simulation to lithic indicators of paleoclimate to evaluate whether or not HadSM3 validly simulates Late Devonian climates. This comparison suggests that the model correctly locates the major climate zones. This study also tests the proposed link between the formation of ocean anoxia and high eccentricity (De Vleeschouwer et al., 2013) by comparing the δ18Ocarb record of the Frasnian–Famennian boundary interval from the Kowala section (Poland) with a simulated time series of astronomically forced changes in mean annual temperature at the paleolocation of Poland. The amplitude of climate change suggested by the isotope record is greater than that of the simulated climate. Hence, astronomically forced climate change may have been further amplified by other feedback mechanisms not considered here (e.g. CO2 and vegetation). Finally, the geologic and simulated time series correlate best when the Frasnian–Famennian negative isotope excursion aligns with maximum mean annual temperature in Poland, which is obtained when eccentricity and obliquity are simultaneously high. This finding supports a connection between Devonian ocean anoxic events and astronomical climate forcing.

@article{Crucifix13aj,
  author = {Crucifix, M.},
  editor = {},
  year = {2013},
  pages = {2253--2267},
  doi = {10.5194/cp-9-2253-2013},
  title = {Why could ice ages be unpredictable?},
  volume = {9},
  journal = {Climate of the Past},
  number = {5}
}

It is commonly accepted that the variations of Earth’s orbit and obliquity control the timing of Pleistocene glacial–interglacial cycles. Evidence comes from power spectrum analysis of palaeoclimate records and from inspection of the timing of glacial and deglacial transitions. However, we do not know how tight this control is. Is it, for example, conceivable that random climatic fluctuations could cause a delay in deglaciation, bad enough to skip a full precession or obliquity cycle and subsequently modify the sequence of ice ages? To address this question, seven previously published conceptual models of ice ages are analysed by reference to the notion of generalised synchronisation. Insight is being gained by comparing the effects of the astronomical forcing with idealised forcings composed of only one or two periodic components. In general, the richness of the astronomical forcing allows for synchronisation over a wider range of parameters, compared to periodic forcing. Hence, glacial cycles may conceivably have remained paced by the astronomical forcing throughout the Pleistocene. However, all the models examined here show regimes of strong structural dependence on parameters. This means that small variations in parameters or random fluctuations may cause significant shifts in the succession of ice ages. Whether the actual system actually resides in such a regime depends on the amplitude of the effects associated with the astronomical forcing, which significantly differ across the different models studied here. The possibility of synchronisation on eccentricity is also discussed and it is shown that a high Rayleigh number on eccentricity, as recently found in observations, is no guarantee of reliable synchronisation.

@article{De-Saedeleer13aa,
  author = {De Saedeleer, B. and Crucifix, M. and Wieczorek, S.},
  editor = {},
  year = {2013},
  pages = {273-294},
  doi = {10.1007/s00382-012-1316-1},
  publisher = {Springer Berlin / Heidelberg},
  title = {Is the astronomical forcing a reliable and unique pacemaker for climate? A conceptual model study},
  volume = {40},
  journal = {Climate Dynamics}
}

@article{Edwards12ab,
  author = {Edwards, T. and Annan, J. and Crucifix, M. and Gebbie, G. and Paul, A.},
  editor = {},
  year = {2012},
  pages = {76-77},
  journal = {PAGES newsletter},
  title = {Best-of-both-worlds estimates for time slices in the past},
  volume = {21},
  number = {2}
}

@article{Hakim12aa,
  author = {Hakim, G. J. and Annan, J. and Brönnimann, S. and Crucifix, M. and Edwards, T. and Goosse, H. and Paul, A. and van der Schrier, G. and Widmann, M.},
  editor = {},
  year = {2012},
  pages = {72-73},
  title = {Overview of data assimlation methods},
  volume = {21},
  journal = {PAGES newsletter},
  number = {2}
}

@article{Bronnimann12aa,
  author = {Brönnimann, S. and Franke, J. and Breitenmoser, P. and Hakim, G. J. and Goosse, H. and Widmann, M. and Crucifix, M. and Gebbie, G. and Annan, J. and van der Schrier, G.},
  editor = {},
  year = {2012},
  pages = {74-75},
  title = {Transient state estimation in paleoclimatology using data assimilation},
  volume = {21},
  journal = {PAGES newsletter},
  number = {2}
}

@article{Annan02aa,
  author = {Annan, J. D. and Crucifix, M. and Edwards, T. and Paul, A.},
  editor = {},
  year = {2012},
  pages = {78-79},
  title = {Parameter estimation using paleodata assimilation},
  volume = {21},
  journal = {PAGES newsletter},
  number = {2}
}

@article{Crucifix12af,
  author = {Crucifix, M. and Harrison, S. and Brierley, C.},
  editor = {},
  year = {2012},
  pages = {539--539},
  journal = {Eos, Transactions American Geophysical Union},
  doi = {10.1029/2012EO510010},
  url = {http://dx.doi.org/10.1029/2012EO510010},
  keywords = {paleoclimatology; climate models; databases; 0473 Paleoclimatology and paleoceanography; 0429 Climate dynamics; 1626 Global climate models},
  title = {Recent and deep pasts in paleoclimate model intercomparison project},
  volume = {93},
  number = {51}
}

@article{Rohling12aa,
  author = {Rohling, E. J. and Sluijs, A. and Dijkstra, H. A. and Köhler, P. and van de Wal, R. S. W. and von der Heydt, A. S. and Beerling, D. J. and Berger, A. and Bijl, P. K. and Crucifix, M. and DeConto, R. and Drijfhout, S. S. and Fedorov, A. and Foster, G. L. and Ganopolski, A. and Hansen, J. and Hönisch, B. and Hooghiemstra, H. and Huber, M. and Huybers, P. and Knutti, R. and Lea, D. W. and Lourens, L. J. and Lunt, D. and Masson-Delmotte, V. and Medina-Elizalde, M. and Otto-Bliesner, B. and Pagani, M. and Pälike, H. and Renssen, H. and Royer, D. L. and Siddall, M. and Valdes, P. and Zachos, J. C. and Zeebe, R. E.},
  editor = {},
  year = {2012},
  pages = {683--691},
  volume = {491},
  doi = {10.1038/nature11574},
  date = {2012/11/29/print},
  url = {http://dx.doi.org/10.1038/nature11574},
  title = {Making sense of palaeoclimate sensitivity},
  journal = {Nature},
  number = {7426}
}

@article{Crucifix12ae,
  author = {Crucifix, M.},
  editor = {},
  year = {2012},
  pages = {1--16},
  volume = {57},
  doi = {10.1016/j.quascirev.2012.09.010},
  date = {2012/12/4/},
  url = {http://www.sciencedirect.com/science/article/pii/S0277379112003472},
  arxiv = {1209.2526},
  keywords = {Modelling; Conceptual; General circulation models; Time-space process; Inference; Bayesian palaeoclimate reconstructions},
  title = {Traditional and novel approaches to palaeoclimate modelling},
  journal = {Quaternary Science Reviews},
  number = {0}
}

@article{De-Vleeschouwer12ad,
  author = {De Vleeschouwer, D. and Da Silva, A. C. and Boulvain, F. and Crucifix, M. and Claeys, P.},
  editor = {},
  year = {2012},
  pages = {337--351},
  doi = {10.5194/cp-8-337-2012},
  date = {2012/02/27},
  url = {http://www.clim-past.net/8/337/2012/},
  publisher = {Copernicus Publications},
  title = {Precessional and half-precessional climate forcing of Mid-Devonian monsoon-like dynamics},
  volume = {8},
  journal = {Climate of the Past},
  number = {1}
}

@article{Crucifix12aa,
  author = {Crucifix, M.},
  editor = {},
  year = {2012},
  pages = {1140-1165},
  volume = {370},
  doi = {10.1098/rsta.2011.0315},
  url = {http://rsta.royalsocietypublishing.org/content/370/1962/1140.abstract},
  title = {Oscillators and relaxation phenomena in Pleistocene climate theory},
  journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences},
  number = {1962}
}

Ice sheets appeared in the northern hemisphere around 3 Ma (million years) ago and glacial–interglacial cycles have paced Earth’s climate since then. Superimposed on these long glacial cycles comes an intricate pattern of millennial and sub-millennial variability, including Dansgaard–Oeschger and Heinrich events. There are numerous theories about these oscillations. Here, we review a number of them in order to draw a parallel between climatic concepts and dynamical system concepts, including, in particular, the relaxation oscillator, excitability, slow–fast dynamics and homoclinic orbits. Namely, almost all theories of ice ages reviewed here feature a phenomenon of synchronization between internal climate dynamics and astronomical forcing. However, these theories differ in their bifurcation structure and this has an effect on the way the ice age phenomenon could grow 3 Ma ago. All theories on rapid events reviewed here rely on the concept of a limit cycle excited by changes in the surface freshwater balance of the ocean. The article also reviews basic effects of stochastic fluctuations on these models, including the phenomenon of phase dispersion, shortening of the limit cycle and stochastic resonance. It concludes with a more personal statement about the potential for inference with simple stochastic dynamical systems in palaeoclimate science.

@article{Crucifix11ab,
  author = {Crucifix, M.},
  editor = {},
  year = {2011},
  pages = {3-32},
  journal = {Revue des Questions Scientifiques},
  volume = {182},
  title = {La climatologie aujourd'hui},
  number = {1}
}

@article{Dubinkina11aa,
  author = {Dubinkina, S. and Goosse, H. and Sallaz-Damaz, Y. and Crespin, E. and Crucifix, M.},
  editor = {},
  year = {2011},
  pages = {3611-3618},
  doi = {10.1142/S0218127411030763},
  title = {Testing a particle filter to reconstruct climate changes over the past centuries},
  volume = {21},
  journal = {International Journal of Bifurcation and Chaos}
}

@article{Crucifix11aa,
  author = {Crucifix, M.},
  editor = {},
  year = {2011},
  pages = {831-842},
  doi = {10.1177/0959683610394883},
  arxiv = {1112.3235C},
  title = {How can a glacial inception be predicted?},
  volume = {21},
  journal = {The Holocene},
  number = {5}
}

@article{ruddiman11ad,
  author = {Ruddiman, W. and Crucifix, M. and Oldfield, F.},
  editor = {Ruddiman, W. F. and Crucifix, M. C. and Oldfield, F. A.},
  year = {2011},
  title = {Introduction to the early-Anthropocene Special Issue},
  pages = {713–713},
  journal = {The Holocene},
  volume = {21},
  doi = {10.1177/0959683611398053},
  url = {http://dx.doi.org/10.1177/0959683611398053},
  publisher = {SAGE Publications},
  number = {5},
  issn = {1477-0911}
}

@article{Deleersnijder10aa,
  author = {Deleersnijder, E. and Bard, E. and Crucifix, M. and Fichefet, T. and Hanaert, E. and Jouzel, J. and Le Treut, H. and Lermusiaux, P. and A., M. and Primau, F. and Wolanski, E.},
  editor = {},
  year = {2010},
  pages = {15},
  journal = {Le Soir},
  date = {6 janvier 2010},
  title = {Le réchauffement climatique est réel et l'Homme en est le principal responsable}
}

@article{Crucifix09aa,
  author = {Crucifix, M. and Rougier, J.},
  editor = {},
  year = {2009},
  pages = {11-31},
  journal = {European Physics Journal - Special Topics},
  volume = {174},
  doi = {10.1140/epjst/e2009-01087-5},
  title = {On the use of simple dynamical systems for climate predictions: A Bayesian prediction of the next glacial inception}
}

Over the last few decades, climate scientists have devoted much effort to the development of large numerical models of the atmosphere and the ocean. While there is no question that such models provide important and useful information on complicated aspects of atmosphere and ocean dynamics, skillful prediction also requires a phenomenological approach, particularly for very slow processes, such as glacial-interglacial cycles. Phenomenological models are often represented as low-order dynamical systems. These are tractable, and a rich source of insights about climate dynamics, but they also ignore large bodies of information on the climate system, and their parameters are generally not operationally defined. Consequently, if they are to be used to predict actual climate system behaviour, then we must take very careful account of the uncertainty introduced by their limitations. In this paper we consider the problem of the timing of the next glacial inception, about which there is on-going debate. Our model is the three-dimensional stochastic system of Saltzman and Maasch (1991), and our inference takes place within a Bayesian framework that allows both for the limitations of the model as a description of the propagation of the climate state vector, and for parametric uncertainty. Our inference takes the form of a data assimilation with unknown static parameters, which we perform with a variant on a Sequential Monte Carlo technique (‘particle filter’). Provisional results indicate peak glacial conditions in 60,000 years.

@article{Otto-Bliesner09aa,
  author = {Otto-Bliesner, B. L. and Schneider, R. and Brady, E. C. and Kucera, M. and Abe-Ouchi, A. and Bard, E. and Braconnot, P. and Crucifix, M. and Hewitt, C. D. and Kageyama, M. and Marti, O. and Paul, A. and Rosell-Mele, A. and Waelbroeck, C. and Weber, S. L. and Weinelt, M. and Yu, Y.},
  editor = {},
  year = {2009},
  pages = {799-815},
  doi = {10.1007/s00382-008-0509-0},
  keywords = {Last glacial maximum; MARGO; PMIP; Tropical oceans; climate sensitivity},
  title = {A comparison of PMIP2 model simulations and the MARGO proxy reconstruction for tropical sea surface temperatures at last glacial maximum},
  volume = {32},
  journal = {Climate Dynamics},
  number = {6}
}

Results from multiple model simulations are used to understand the tropical sea surface temperature (SST) response to the reduced greenhouse gas concentrations and large continental ice sheets of the last glacial maximum (LGM). We present LGM simulations from the Paleoclimate Modelling Intercomparison Project, Phase 2 (PMIP2) and compare these simulations to proxy data collated and harmonized within the Multiproxy Approach for the Reconstruction of the Glacial Ocean Surface Project (MARGO). Five atmosphere-ocean coupled climate models (AOGCMs) and one coupled model of intermediate complexity have PMIP2 ocean results available for LGM. The models give a range of tropical (defined for this paper as 15A degrees S-15A degrees N) SST cooling of 1.0-2.4A degrees C, comparable to the MARGO estimate of annual cooling of 1.7 +/- A 1A degrees C. The models simulate greater SST cooling in the tropical Atlantic than tropical Pacific, but interbasin and intrabasin variations of cooling are much smaller than those found in the MARGO reconstruction. The simulated tropical coolings are relatively insensitive to season, a feature also present in the MARGO transferred-based estimates calculated from planktonic foraminiferal assemblages for the Indian and Pacific Oceans. These assemblages indicate seasonality in cooling in the Atlantic basin, with greater cooling in northern summer than northern winter, not captured by the model simulations. Biases in the simulations of the tropical upwelling and thermocline found in the preindustrial control simulations remain for the LGM simulations and are partly responsible for the more homogeneous spatial and temporal LGM tropical cooling simulated by the models. The PMIP2 LGM simulations give estimates for the climate sensitivity parameter of 0.67A degrees-0.83A degrees C per Wm(-2), which translates to equilibrium climate sensitivity for doubling of atmospheric CO2 of 2.6-3.1A degrees C.

@article{Rojas09aa,
  author = {Rojas, M. and Moreno, P. I. and Kageyama, M. and Crucifix, M. and Hewitt, C. and Abe-Ouchi, A. and Ohgaito, R. and Brady, E. C. and Hope, P.},
  editor = {},
  year = {2009},
  pages = {525-548},
  doi = {10.1007/s00382-008-0421-7},
  title = {The Southern Westerlies during the last glacial maximum in PMIP2 simulations},
  volume = {32},
  journal = {Climate Dynamics},
  number = {4}
}

The Southern Hemisphere westerly winds are an important component of the climate system at hemispheric and global scales. Variations in their intensity and latitudinal position through an ice-age cycle have been proposed as important drivers of global climate change due to their influence on deep-ocean circulation and changes in atmospheric CO2. The position, intensity, and associated climatology of the southern westerlies during the last glacial maximum (LGM), however, is still poorly understood from empirical and modelling standpoints. Here we analyse the behaviour of the southern westerlies during the LGM using four coupled ocean-atmosphere simulations carried out by the Palaeoclimate Modelling Intercomparison Project Phase 2 (PMIP2). We analysed the atmospheric circulation by direct inspection of the winds and by using a cyclone tracking software to indicate storm tracks. The models suggest that changes were most significant during winter and over the Pacific ocean. For this season and region, three out four models indicate decreased wind intensities at the near surface as well as in the upper troposphere. Although the LGM atmosphere is colder and the equator to pole surface temperature gradient generally increases, the tropospheric temperature gradients actually decrease, explaining the weaker circulation. We evaluated the atmospheric influence on the Southern Ocean by examining the effect of wind stress on the Ekman pumping. Again, three of the models indicate decreased upwelling in a latitudinal band over the Southern Ocean. All models indicate a drier LGM than at present with a clear decrease in precipitation south of 40A degrees S over the oceans. We identify important differences in precipitation anomalies over the land masses at regional scale, including a drier climate over New Zealand and wetter over NW Patagonia.

@article{Yin09aa,
  author = {Yin, Q. Z. and Berger, A. and Crucifix, M.},
  editor = {},
  year = {2009},
  pages = {229-243},
  title = {Individual and combined effects of ice sheets and precession on MIS-13 climate},
  volume = {5},
  journal = {Climate of the Past},
  number = {2}
}

An Earth System Model of Intermediate Complexity is used to investigate the role of insolation and of the size of ice sheets on the regional and global climate of marine isotope stage (MIS) 13. The astronomical forcing is selected at two dates with opposite precession, one when northern hemisphere (NH) summer occurs at perihelion (at 506 ka (1 ka=1000 years) BP), and the other when it occurs at aphelion (at 495 ka BP). Five different volumes of the Eurasian ice sheet (EA) and North American ice sheet (NA), ranging from 0 to the Last Glacial Maximum (LGM) one, are used. The global cooling due to the ice sheets is mainly related to their area, little to their height. The regional cooling and warming anomalies caused by the ice sheets intensify with increasing size. Precipitation over different monsoon regions responds differently to the size of the ice sheets. Over North Africa and India, precipitation decreases with increasing ice sheet size due to the southward shift of the Intertropical Convergence Zone (ITCZ), whatever the astronomical configuration is. However, the situation is more complicated over East Asia. The ice sheets play a role through both reducing the land/ocean thermal contrast and generating a wave train which is topographically induced by the EA ice sheet. This wave train contributes to amplify the Asian land/ocean pressure gradient in summer and finally reinforces the precipitation. The presence of this wave train depends on the combined effect of the ice sheet size and insolation. When NH summer occurs at perihelion, the EA is able to induce this wave train whatever its size is, and this wave train plays a more important role than the reduction of the land/ocean thermal contrast. Therefore, the ice sheets reinforce the summer precipitation over East China whatever their sizes are. However, when NH summer occurs at aphelion, there is a threshold in the ice volume beyond which the wave train is not induced anymore. Therefore, below this threshold, the wave train effect is dominant and the ice sheets reinforce precipitation over East China. Beyond this threshold, the ice sheets reduce the precipitation mainly through reducing the land/ocean thermal contrast.

@article{cp-5-707-2009,
  author = {Crucifix, M. and Claussen, M. and Ganssen, G. and Guiot, J. and Guo, Z. and Kiefer, T. and Loutre, M. F. and Rousseau, D. D. and Wolff, E.},
  editor = {},
  year = {2009},
  pages = {707--711},
  url = {http://www.clim-past.net/5/707/2009/},
  title = {Preface "Climate change: from the geological past to the uncertain future -- a symposium honouring André Berger"},
  volume = {5},
  journal = {Climate of the Past},
  number = {4}
}

@article{Goidts09aa,
  author = {Goidts, E. and van Wesemael, B. and Crucifix, M.},
  editor = {},
  year = {2009},
  pages = {723-739},
  journal = {European Journal of Soil Science},
  doi = {10.1111/j.1365-2389.2009.01157.x},
  publisher = {WILEY-BLACKWELL PUBLISHING, INC},
  title = {Magnitude and sources of uncertainties in soil organic carbon (SOC) stock assessments at various scales},
  volume = {60},
  number = {5}
}

Uncertainties in soil organic carbon (SOC) stock assessments are rarely quantified even though they are critical in determining the significance of the results. Previous studies on this topic generally focused on a single variable involved in the SOC stock calculation (SOC concentration, sampling depth, bulk density and rock fragment content) or on a single scale, rather than using an integrated approach (i.e. taking into account interactions between variables). This study aims to apply such an approach to identify and quantify the uncertainties in SOC stock assessments for different scales and spatial landscape units (LSU) under agriculture. The error propagation method (delta method) was used to quantify the relative contribution of each variable and interaction involved to the final SOC stock variability. Monte Carlo simulations were used to cross-check the results. Both methods converged (r2=0.78). As expected, the coefficient of variation of the SOC stock increased across scales (from 5 to 35%), and was higher for grassland than for cropland. Although the main source of uncertainty in the SOC stock varied according to the scale and the LSU considered, the variability of SOC concentration (due to errors from the laboratory and to the high SOC spatial variability) and of the rock fragment content were predominant. When assessing SOC stock at the landscape scale, one should focus on the precision of SOC analyses from the laboratory, the reduction of SOC spatial variability (using bulk samples, accurate re-sampling, high sampling density or stratified sampling), and the use of equivalent masses for SOC stock comparison. The regional SOC stock monitoring of agricultural soils in southern Belgium allows the detection of an average SOC stock change of 20% within 11 years if very high rates of SOC stock changes occur (1 t C ha-1 year-1).

@article{Crucifix09ah,
  author = {Crucifix, M.},
  editor = {},
  year = {2009},
  pages = {371-402},
  journal = {European Review},
  doi = {10.1017/S106279870900074X},
  volume = {17},
  number = {2}
}

@article{2008AGUFM.U33B..01L,
  author = {Loutre, M. and Crucifix, M. and Berger, A.},
  editor = {},
  year = {2008},
  pages = {B1},
  keywords = {4901 Abrupt/rapid climate change (1605), 4910 Astronomical forcing, 4934 Insolation forcing, 4946 Milankovitch theory},
  title = {Chasing An Analogue For The Holocene : The Astronomical Forcing},
  journal = {AGU Fall Meeting Abstracts}
}

@article{yin08,
  author = {Yin, Q. and Berger, A. and Driesschaert, E. and Goosse, H. and Loutre, M. F. and Crucifix, M.},
  editor = {},
  year = {2008},
  pages = {79--90},
  doi = {10.5194/cp-4-79-2008},
  url = {http://www.clim-past.net/4/79/2008/},
  issn = {1814-9324},
  keywords = {monsoon, MIS 13},
  title = {The Eurasian ice sheet reinforces the East Asian summer monsoon during the interglacial 500 000 years ago},
  volume = {4},
  journal = {Climate of the Past},
  number = {2}
}

@article{Murakami08aa,
  author = {Murakami, S. and Ohgaito, R. and Abe-Ouchi, A. and Crucifix, M. and Otto-Bliesner, B. L.},
  editor = {},
  year = {2008},
  pages = {5008-5033},
  doi = {10.1175/2008JCLI2104.1},
  date = {OCT 2008},
  title = {Global-scale energy and freshwater balance in glacial climate: A comparison of three PMIP2 LGM simulations},
  volume = {21},
  journal = {Journal of Climate},
  number = {19}
}

Three coupled atmosphere-ocean general circulation model (AOGCM) simulations of the Last Glacial Maximum (I-GM: about 21000 yr before present), conducted under the protocol of the second phase of the Paleoclimate Modelling Intercomparison Project (PMIP2), have been analyzed from a viewpoint of large-scale energy and freshwater balance. Atmospheric latent heat (LH) transport decreases at most latitudes due to reduced water vapour content in the lower troposphere. and dry static energy (DSE) transport in northern midlatitudes increases and changes the intensity contrast between the Pacific and Atlantic regions due to enhanced stationary waves over the North American ice Sheets. In low latitudes. even with an intensified Hadley circulation in the Northern Hemisphere (NH), reduced DSE transport by the mean zonal circulation as well as a reduced equatorward LH transport is observed. The oceanic heat transport at NH midlatitudes increases owing to intensified subpolar gyres, and the Atlantic heat transport at low latitudes increases in all models whether or not meridional overturning circulation (MOC) intensifies. As a result, total poleward energy transport at the LGM increases in NH mid- and low latitudes in all models. Oceanic freshwater transport decreases. compensating for the response of the atmospheric water vapor transport. These responses in the atmosphere and ocean make the northern North Atlantic Ocean cold and relatively fresh. and the Southern Ocean relatively warm and saline. This is a common and robust feature in all odels. The resultant ocean densities and ocean MOC response. however. show model dependency.

@article{Crucifix08aj,
  author = {Crucifix, M.},
  editor = {},
  year = {2008},
  pages = {47-48},
  doi = {10.1038/456047a},
  date = {NOV 6 2008},
  title = {Global change: Climate's astronomical sensors},
  volume = {456},
  journal = {Nature},
  number = {7218}
}

@article{taylor06aprp,
  author = {Taylor, K. E. and Crucifix, M. and Braconnot, P. and Hewitt, C. D. and Doutriaux, C. and Webb, M. J. and Broccoli, A. J. and Mitchell, J. F. B.},
  editor = {},
  year = {2007},
  pages = {2530-2543},
  doi = {10.1175/JCLI14143.1},
  keywords = {climate sensitivity, prp},
  title = {Estimating shortwave radiative forcing and response in climate models},
  volume = {20},
  journal = {Journal of Climate}
}

@article{Weber2006The-modern-and-,
  author = {Weber, S. L. and Drijfhout, S. S. and Abe-Ouchi, A. and Crucifix, M. and Eby, M. and Ganopolski, A. and Murakami, M. and Otto-Bliesner, B. and Peltier, W. R.},
  editor = {},
  year = {2007},
  pages = {51-64},
  url = {http://www.clim-past.net/3/51/2007_/cp-3-51-2007.html},
  keywords = {LGM, ocean models, thermohaline circulation, PMIP2},
  title = {The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled experiments},
  volume = {3},
  journal = {Climate of the Past}
}

@article{braconnot07pmip2,
  author = {Braconnot, P. and Otto-Bliesner, B. L. and Harrison, S. and Joussaume, S. and Peterschmitt, J. Y. and Abe-Ouchi, A. and Crucifix, M. and Driesschaert, E. and Fichefet, T. and Hewitt, C. D. and Kageyama, M. and Kitoh, A. and Laîné, A. and Loutre, M. F. and Marti, O. and Merkel, U. and Ramstein, G. and Valdes, P. and Weber, S. L. and Yu, Y. and Zhao, Y.},
  editor = {},
  year = {2007},
  pages = {279-296},
  url = {www.clim-past.net/3/279/2007_/},
  keywords = {PMIP2},
  title = {Results of PMIP2 coupled simulations of the Mid Holocene and Last Glacial Maximum -- Part 2: feedbacks with emphasis on the location of the ITCZ and mid- and high latitudes heat budget},
  volume = {3},
  journal = {Climate of the Past}
}

@article{braconnot07pmip1,
  author = {Braconnot, P. and Otto-Bliesner, B. L. and Harrison, S. and Joussaume, S. and Peterschmitt, J. Y. and Abe-Ouchi, A. and Crucifix, M. and Driesschaert, E. and Fichefet, T. and Hewitt, C. D. and Kageyama, M. and Kitoh, A. and La\^\iné, A. and Loutre, M. F. and Marti, O. and Merkel, U. and Ramstein, G. and Valdes, P. and Weber, S. L. and Yu, Y. and Zhao, Y.},
  editor = {},
  year = {2007},
  pages = {261-277},
  doi = {10.5194/cp-3-261-2007},
  url = {www.clim-past.net/3/261/2007/},
  title = {Results of PMIP2 coupled simulations of the Mid Holocene and Last Glacial Maximum -- Part 1: experiments and large-scale features},
  volume = {3},
  journal = {Climate of the Past}
}

@article{Otto-Bliesner07aa,
  author = {Otto-Bliesner, B. L. and Hewitt, C. D. and Marchitto, T. M. and Brady, E. and Abe-Ouchi, A. and Crucifix, M. and Murakami, S. and Weber, S. L.},
  editor = {},
  year = {2007},
  pages = {L12706},
  title = {Last Glacial Maximum ocean thermohaline circulation: PMIP2 model intercomparisons and data constraints},
  volume = {34},
  journal = {Geophysical Research Letters}
}

The ocean thermohaline circulation is important for transports of heat and the carbon cycle. We present results from PMIP2 coupled atmosphere-ocean simulations with four climate models that are also being used for future assessments. These models give very different glacial thermohaline circulations even with comparable circulations for present. An integrated approach using results from these simulations for Last Glacial Maximum (LGM) with proxies of the state of the glacial surface and deep Atlantic supports the interpretation from nutrient tracers that the boundary between North Atlantic Deep Water and Antarctic Bottom Water was much shallower during this period. There is less constraint from this integrated reconstruction regarding the strength of the LGM North Atlantic overturning circulation, although together they suggest that it was neither appreciably stronger nor weaker than modern. Two model simulations identify a role for sea ice in both hemispheres in driving the ocean response to glacial forcing.

@article{edwards07pg,
  author = {Edwards, T. L. and Crucifix, M. and Harrison, S. P.},
  editor = {},
  year = {2007},
  pages = {481},
  journal = {Prog. Phys. Geogr.},
  doi = {10.1177/0309133307083295},
  keywords = {climate sensitivity, LGM, assimilation},
  title = {Using the past to constrain the future: how the palaeorecord can improve estimates of global warming},
  volume = {31}
}

@article{weber07aa,
  author = {Weber, S. L. and Drijfhout, S. S. and Abe-Ouchi, A. and Crucifix, M. and Eby, M. and Ganopolski, A. and Murakami, S. and Otto-Bliesner, B. and Peltier, W. R.},
  editor = {},
  year = {2007},
  title = {The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations},
  pages = {51–64},
  journal = {Climate of the Past},
  volume = {3},
  doi = {10.5194/cp-3-51-2007},
  url = {http://dx.doi.org/10.5194/cp-3-51-2007},
  publisher = {Copernicus GmbH},
  number = {1},
  issn = {1814-9332}
}

@article{hewitt06freshwater,
  author = {Hewitt, C. D. and Broccoli, A. J. and Crucifix, M. and Gregory, J. M. and Mitchell, J. F. B. and Stouffer, R. J.},
  editor = {},
  year = {2006},
  pages = {4436---4447},
  doi = {10.1175/JCLI3867.1},
  title = {The effect of a large freshwater perturbation on the Glacial Atlantic Ocean using a coupled general circulation model},
  volume = {19},
  journal = {Journal of Climate}
}

@article{johns06hadgem1,
  author = {Johns, T. C. and Durman, C. F. and Banks, H. T. and Roberts, M. J. and McLaren, A. J. and Ridley, J. K. and Senior, C. A. and Williams, K. D. and Jones, A. and Rickard, G. J. and Cusack, S. and Ingram, W. J. and Crucifix, M. and Sexton, D. M. H. and Joshi, M. M. and Dong, B. W. and Spencer, H. and Hill, R. S. R. and Gregory, J. M. and Keen, A. B. and Pardaens, A. K. and Lowe, J. A. and Bodas-Salcedo, A. and Stark, S. and Searl, Y.},
  editor = {},
  year = {2006},
  pages = {1327-1353},
  title = {The new Hadley Centre climate model HadGEM1: Evaluation of coupled simulations},
  volume = {19},
  journal = {Journal of Climate},
  number = {7}
}

@article{crucifix06lgm,
  author = {Crucifix, M.},
  editor = {},
  year = {2006},
  pages = {L18701},
  doi = {10.1029/2006GL027137},
  title = {Does the Last Glacial Maximum constrain climate sensitivity?},
  volume = {33},
  journal = {Geophysical Research Letters}
}

Four simulations with atmosphere-ocean climate models have been produced using identical Last Glacial Maximum ice sheets, topography and greenhouse gas concentrations. Compared to the pre-industrial, the diagnosed radiative feedback parameter ranges between −1.30 and −1.18 Wm−2K−1, the tropical ocean sea-surface temperature decreases between 1.7 and 2.7\,^∘C, and Antarctic surface air temperature decreases by 7 to 11\,^∘C. These values are all compatible with observational estimates, except for a tendency to underestimate the tropical ocean cooling. On the other hand, the same models have a climate sensitivity to CO2 concentration doubling ranging between 2.1 and 3.9 K. It is therefore inappropriate to simply scale an observational estimate of LGM temperature to predict climate sensitivity. This is mainly a consequence of the non-linear character of the cloud (mainly shortwave) feedback at low latitudes. Changes in albedo and cloud cover at mid and high latitudes are also important, but less so.

@article{masson06polar,
  author = {Masson, V. and Kageyama, M. and Braconnot, P. and Charbit, S. and Krinner, G. and Ritz, C. and Guilyardi, E. and Hoffman, G. and Jouzel, J. and Abe-Ouchi, A. and Crucifix, M. and Gladstone, R. and Hewitt, C. D. and Kitoh, A. and Legrande, A. and Marti, O. and Merkel, U. and Motoi, T. and Ohgaito, R. and Otto-Bliesner, B. and Peltier, W. R. and Ross, I. and Valdes, P. J. and Vettoretti, G. and Weber, S. L. and Wolk, F.},
  editor = {},
  year = {2006},
  pages = {513-519},
  doi = {10.1007/s00382-005-0081-9},
  title = {Past and future polar amplification of climate change: climate mode intercomparison and ice-core constraints},
  volume = {26},
  journal = {Climate Dynamics},
  number = {5}
}

@article{kageyama2006qsr,
  author = {Kageyama, M. and La\^\iné, A. and Abe-Ouchi, A. and Braconnot, P. and Cortijo, E. and Crucifix, M. and de Vernal, A. and Guiot, J. and Hewitt, C. D. and Kitoh, A. and Kucera, M. and Marti, O. and Ohgaito, R. and Otto-Bliesner, B. and Peltier, W. R. and Rosell-Melé, A. and Vettoretti, G. and Weber, S. L. and Yu, Y. and Members, MARGO Project},
  editor = {},
  year = {2006},
  pages = {2082-2102},
  doi = {10.1016/J.quascirev.2006.02.010},
  keywords = {LGM, GCM, PMIP2, terrestrial data, ocean data, pollen},
  title = {Last Glacial Maximum temperatures over the North Atlantic, Europe and western Siberia: a comparison between PMIP models, MARGO sea-surface temperatures and pollen-based reconstructions},
  volume = {25},
  journal = {Quat. Sci. Rev.},
  number = {17-18}
}

@article{crucifix06eos,
  author = {Crucifix, M. and Berger, A.},
  editor = {},
  year = {2006},
  pages = {352},
  keywords = {Ruddiman hypothesis, analogs},
  title = {How long will our interglacial be?},
  volume = {87},
  journal = {Eos, Trans. Am. Geophys. Union},
  number = {35},
  doi = {10.1029/2006EO350007}
}

@article{Crucifix2006The-climate-res,
  author = {Crucifix, M. and Loutre, M. F. and Berger, A.},
  editor = {},
  year = {2006},
  pages = {213-226},
  doi = {10.1007/s11214-006-9058-1},
  keywords = {Pleistocene, EMICS, ice sheet model},
  title = {The climate response to the astronomical forcing},
  volume = {125},
  journal = {Space Sci. Rev.},
  number = {1-4}
}

@article{banks07niche,
  author = {Banks, W. E. and d'Errico, F. and Dibble, H. and Krishtalka, M. and West, D. and Olsewski, D. and Peterson, A. T. and Anderson, D. G. and Gillamn, J. C. and Montet-White, A. and Crucifix, M. and Marean, C. W. and Sanchez-Goñi, M. F. and Wohlfarth, B. and Vanhaeran, M.},
  editor = {},
  year = {2006},
  journal = {Paleoanthropology},
  keywords = {anthropology, LGM, Holocene},
  title = {Eco-cultural niche modeling: new tools for reconstructing the geography and ecology of past human populations},
  volume = {1},
  number = {68-83}
}

@article{petoukhov05,
  author = {Petoukhov, V. and Claussen, M. and Berger, A. and Crucifix, M. and Eby, M. and Eliseev, A. V. and Fichefet, T. and Ganopolski, A. and Goosse, H. and Kamenkovich, I. and Mokhov, I. and Montoya, M. and Mysak, L. A. and Sokolov, A. and Stone, P. and Wang, Z. and Weaver, A. J.},
  editor = {},
  year = {2005},
  pages = {363-385},
  doi = {10.1007/s00382-005-0042-3},
  title = {EMIC intercomparison project (EMIP-CO$_2$): comparative analysos of EMIC simulations of climae, and of equilibrium and transient responses to atmospheric CO$_2$ doubling},
  volume = {25},
  journal = {Climate Dynamics}
}

@article{Sanchez05,
  author = {Sanchez-Goñi, M. F. and Loutre, M. F. and Crucifix, M. and Peyron, O. and Santos, L. and Duprat, J. and Turon, J. L. and Peypouquet, J. P.},
  editor = {},
  year = {2005},
  pages = {111-130},
  volume = {231},
  title = {Increasing vegetation and climate gradient in Western Europe over the Last Glacial Inception (122-110 ka): models-data comparison},
  journal = {Earth and Planetary Science Letters}
}

@article{crucifix05anthropocene,
  author = {Crucifix, M. and Loutre, M. F. and Berger, A.},
  editor = {},
  year = {2005},
  pages = {419-426},
  title = {Commentary on "the anthropogenic greenhouse era began thousands of years ago"},
  volume = {69},
  journal = {Climatic Change}
}

@article{crucifix05carbon,
  author = {Crucifix, M.},
  editor = {},
  year = {2005},
  pages = {PA4020},
  doi = {10.1029/2005PA001131},
  title = {Carbon isotopes in the glacial ocean: a model study},
  volume = {20},
  journal = {Paleoceanography}
}

@article{crucifix05eos,
  author = {Crucifix, M. and Braconnot, P. and Harrison, S. P. and Otto-Bliesner, B.},
  editor = {},
  year = {2005},
  pages = {264},
  title = {Second phase of Paleoclimate Modelling Intercomparison Project},
  volume = {86},
  journal = {Eos, Trans. Am. Geophys. Union},
  number = {28}
}

@article{crucifix05impactveg,
  author = {Crucifix, M. and Hewitt, C. D.},
  editor = {},
  year = {2005},
  pages = {447-459},
  doi = {10.1007/s00382-005-0013-8},
  title = {Impact of vegetation changes on the dynamics of the atmosphere at the Last Glacial Maximum},
  volume = {25},
  journal = {Climate Dynamics},
  number = {5}
}

Much work is under way to identify and quantify the feedbacks between vegetation and climate. Palaeoclimate modelling may provide a mean to address this problem by comparing simulations with proxy data. We have performed a series of four simulations of the Last Glacial Maximum (LGM, 21,000 years ago) using the climate model HadSM3, to test the sensitivity of climate to various changes in vegetation: a global change (according to a previously discussed simulation of the LGM with HadSM3 coupled to the dynamical vegetation model TRIFFID); a change only north of 35\,^∘N; a change only south of 35\,^∘N; and a variation in stomatal opening induced by the reduction in atmospheric CO2 concentration. We focus mainly on the response of temperature, precipitation, and atmosphere dynamics. The response of continental temperature and precipitation mainly results from regional interactions with vegetation. In Eurasia, particularly Siberia and Tibet, the response of the biosphere substantially enhances the glacial cooling through a positive feedback loop between vegetation, temperature, and snow-cover. In central Africa, the decrease in tree fraction reduces the amount of precipitation. Stomatal opening is not seen to play a quantifiable role. The atmosphere dynamics, and more specifically the Asian summer monsoon system, are significantly altered by remote changes in vegetation: the cooling in Siberia and Tibet act in concert to shift the summer subtropical front southwards, weaken the easterly tropical jet and the momentum transport associated with it. By virtue of momentum conservation, these changes in the mid-troposphere circulation are associated with a slowing of the Asian summer monsoon surface flow. The pattern of moisture convergence is slightly altered, with moist convection weakening in the western tropical Pacific and strengthening north of Australia.

@article{crucifix05veglgm,
  author = {Crucifix, M. and Betts, R. A. and Hewitt, C. D.},
  editor = {},
  year = {2005},
  pages = {295-312, 10.1016/j.gloplach.20},
  title = {Pre-industrial-potential and Last Glacial Maximum global vegetation simulated with a coupled climate-biosphere model: Diagnosis of bioclimatic relationships},
  volume = {45},
  journal = {Global and Planetary Change},
  number = {4}
}

@article{crucifix05vegvar,
  author = {Crucifix, M. and Betts, R. A. and Cox, P. M.},
  editor = {},
  year = {2005},
  pages = {457 - 467, 10.1007/s00382-004-},
  title = {Vegetation and climate variability : a GCM modelling study},
  volume = {24},
  journal = {Climate Dynamics},
  number = {5}
}

@article{Rahmstorf05aa,
  author = {Rahmstorf, S. and Crucifix, M. and Ganopolski, A. and Goosse, H. and Kamenkovich, I. and Knutti, R. and Lohmann, G. and Marsh, R. and Mysak, L. A. and Wang, Z. and Weaver, A. J.},
  editor = {},
  year = {2005},
  pages = {L23605},
  date = {2005/12/06},
  url = {http://dx.doi.org/10.1029/2005GL023655},
  keywords = {ocean circulation, EMICS, hysteresis},
  title = {Thermohaline circulation hysteresis: A model intercomparison},
  volume = {32},
  journal = {Geophysical Research Letters},
  number = {23}
}

We present results from an intercomparison of 11 different climate models of intermediate complexity, in which the North Atlantic Ocean was subjected to slowly varying changes in freshwater input. All models show a characteristic hysteresis response of the thermohaline circulation to the freshwater forcing; which can be explained by Stommel’s salt advection feedback. The width of the hysteresis curves varies between 0.2 and 0.5 Sv in the models. Major differences are found in the location of present-day climate on the hysteresis diagram. In seven of the models, present-day climate for standard parameter choices is found in the bi-stable regime, in four models this climate is in the mono-stable regime. The proximity of the present-day climate to the Stommel bifurcation point, beyond which North Atlantic Deep Water formation cannot be sustained, varies from less than 0.1 Sv to over 0.5 Sv.

@article{schmittner04eos,
  author = {Schmittner, A. and Sarnthein, M. and Hinkel, H. and Bartoli, G. and Bicvkert, T. and Crucifix, M. and Crudeli, D. and Groenveld, J. and Kösters, F. and Mikolajewicz, U. and Millo, C. and Reijmer, J. and Schäfer, P. and Schmidt, D. and Schneider, B. and Schulz, M. and Steph, S. and Tiedemann, R. and Veinelt, M. and Zuvela, M.},
  editor = {},
  year = {2004},
  pages = {526},
  journal = {Eos, Trans. Am. Geophys. Union},
  title = {Global impact of the Panamian seaway closure},
  volume = {85},
  number = {49},
  doi = {10.1029/2004EO490010}
}

@article{krinner04lakes,
  author = {Krinner, G. and Mangerud, J. and Jacobson, M. and Crucifix, M. and Ritz, C. and Svendsen, J.},
  editor = {},
  year = {2004},
  pages = {429-432},
  volume = {427},
  keywords = {dammed lakes, GCM, Pleistocene, Weschelian},
  title = {Enhancement of ice sheet growth by ice dammed lakes},
  journal = {Nature},
  doi = {10.1038/nature02233}
}

@article{brovkin03cc,
  author = {Brovkin, V. and Levis, S. and Loutre, M. F. and Crucifix, M. and Claussen, M. and Ganopolski, A. and Kubatzki, C. and Petoukhov, V.},
  editor = {},
  year = {2003},
  pages = {119-138},
  title = {Stability analysis of the climate-vegetation system in the northern high latitudes},
  volume = {57},
  journal = {Climatic Change},
  number = {1-2}
}

@article{berger03,
  author = {Berger, A. and Loutre, M. F. and Crucifix, M.},
  editor = {},
  year = {2003},
  pages = {117-138},
  journal = {Surv. Geoph},
  title = {The earth climate in the next hundred thousand years},
  volume = {24}
}

@article{Crucifix02aa,
  author = {Crucifix, M. and Loutre, F.},
  editor = {},
  year = {2002},
  pages = {417--433},
  doi = {10.1007/s00382-002-0234-z},
  title = {Transient simulations over the last interglacial period (126-115 kyr BP): feedback and forcing analysis},
  volume = {19},
  journal = {Climate Dynamics},
  number = {5}
}

@article{crucifix02holocene,
  author = {Crucifix, M. and Loutre, M. F. and Tulkens, P. and Fichefet, T. and Berger, A.},
  editor = {},
  year = {2002},
  pages = {43-60},
  doi = {10.1007/s00382-001-0208-6},
  title = {Climate evolution during the Holocene: A study with an Earth system model of intermediate complexity},
  volume = {19},
  journal = {Climate Dynamics}
}

@article{crucifix02pal,
  author = {Crucifix, M. and Berger, A.},
  editor = {},
  year = {2002},
  pages = {doi:10.1029/2001PA000702},
  title = {Modelling ocean-ice sheets interactions during the last deglaciation},
  volume = {17},
  journal = {Paleoceanography},
  number = {4},
  doi = {10.1029/2001PA000702}
}

@article{claussen02emic,
  author = {Claussen, M. and Mysak, L. and Weaver, A. and Crucifix, M. and Fichefet, T. and Loutre, M. F. and Weber, S. and Alcamo, J. and Alexeev, V. and Berger, A. and Calov, R. and Ganopolski, A. and Goosse, H. and Lohmann, G. and Lunkeit, F. and Mokhov, I. and Petoukhov, V. and Stone, P. and Wang, Z.},
  editor = {},
  year = {2002},
  pages = {579--586},
  doi = {10.1007/s00382-001-0200-1},
  keywords = {EMICS},
  title = {Earth system models of intermediate complexity: closing the gap in the spectrum of climate system models},
  volume = {18},
  journal = {Climate Dynamics},
  number = {7}
}

@article{crucifix02ab,
  author = {Crucifix, M. and Berger, A.},
  editor = {},
  year = {2002},
  title = {Simulation of ocean-ice sheet interactions during the last deglaciation},
  pages = {6–1–6–18},
  journal = {Paleoceanography},
  volume = {17},
  doi = {10.1029/2001pa000702},
  url = {http://dx.doi.org/10.1029/2001PA000702},
  publisher = {American Geophysical Union (AGU)},
  number = {4},
  issn = {0883-8305}
}

@article{crucifix01isostasy,
  author = {Crucifix, M. and Loutre, M. F. and Lambeck, K. and Berger, A.},
  editor = {},
  year = {2001},
  pages = {623-633},
  volume = {184},
  title = {Effect of Isostatic Rebound on Modelled Ice Volume Variations over the last 200 kyr},
  journal = {Earth and Planetary Science Letters}
}

@article{Galtayries99aa,
  author = {Galtayries, A. and Crucifix, M. and Blanchard, G. and Terwagne, G. and Sporken, R.},
  editor = {},
  year = {1999},
  pages = {159-163},
  journal = {Applied Surface Science},
  volume = {142},
  keywords = {ceria-zirconia mixed oxide; thin film; XPS; interface; solid solution},
  title = {Preparation and characterisation of mixed oxide (Ce,Zr)O-2 thin films on Si(111) substrates}
}

We have grown thin films of mixed oxides on Si (111) substrates by electron beam evaporation of pressed CexZr1-xO2 pellets. The growth was initiated under UHV environment, and proceeded then under O-2 atmosphere. A multitechnique approach (XPS, AES, LEED, XRD, RES) was used to characterise the chemical and structural composition of the film as well as their interface with the substrate. The films are about 100 Angstrom thick and present at least two phases corresponding to ZrO2 and CeO2. XPS depth profiles showed the following structure, starting from the substrate: a region of interdiffused Zr and Si, a CeSiOx layer mixed with ZrO2 and finally the homogeneous (Ce,Zr)O-2 film, enriched in Ce with respect to the pellet. (C) 1999 Elsevier Science B.V. All rights reserved.