.. .. Supplementary-material,

, Conclusion of the chapter

. .. Numerical-experiments,

.. .. Discussion,

, Conclusion of the chapter

B. Abe-ouchi, A. Saito, F. Kawamura, K. Raymo, M. E. Okuno et al., Insolation-driven 100,000-year glacial cycles and hysteresis of ice-sheet volume, Nature, vol.500, p.190, 2013.

D. Adalsteinsson and J. Sethian, The Fast Construction of Extension Velocities in Level Set Methods, J. Comput. Phys, vol.148, pp.2-22, 1999.

J. Ahn, E. J. Brook, and C. Buizert, Response of atmospheric CO 2 to the abrupt cooling event 8200 years ago, Geophys. Res. Lett, vol.41, pp.604-609, 2014.

D. W. Allan, Statistics of atomic frequency standards, Proc. IEEE, vol.54, pp.221-230, 1966.

R. B. Alley, Firn densification by grain-boundary sliding: a first model, J. Phys. Colloques, vol.48, pp.1-249, 1987.
URL : https://hal.archives-ouvertes.fr/jpa-00226281

D. L. Anderson and C. S. Benson, The densification and diagenesis of snow, Ice and Snow: Properties, Processes, and Applications, pp.391-411, 1963.

L. Arnaud, J. Barnola, and P. Duval, Physical modeling of the densification of snow/-firn and ice in the upper part of polar ice sheets, Phys. Ice Core Rec, pp.285-305, 2000.

E. Arzt, The influence of an increasing particle coordination on the densification of spherical powders, Acta Metall, vol.30, pp.1883-1890, 1982.

E. Arzt, M. F. Ashby, and K. E. Easterling, Practical applications of hotisostatic pressing diagrams: four case studies, Metall. Trans. A, vol.14, pp.211-221, 1983.

M. Ashby, A first report on sintering diagrams, Acta Metall, vol.22, pp.275-289, 1974.

H. Bader, Density of ice as a function of temperature and stress, 1964.

G. Baglietto and E. V. Albano, Finite-size scaling analysis and dynamic study of the critical behavior of a model for the collective displacement of self-driven individuals, Phys. Rev

E. , , vol.021, p.125, 2008.

P. R. Barnes, E. W. Wolff, H. M. Mader, R. Udisti, E. Castellano et al., Evolution of chemical peak shapes in the Dome C, Antarctica, ice core, J. Geophys. Res. Atmos, vol.108, 2003.

J. Barnola, D. Raynaud, Y. S. Korotkevich, and C. Lorius, Vostok ice core provides 160,000-year record of atmospheric CO2, Nature, vol.329, p.408, 1987.

J. M. Barnola, R. Pierritz, C. Goujon, P. Duval, and E. Boller, 3D reconstruction of the Vostok firn structure by X-ray tomography, vol.97, pp.80-84, 2004.

M. Battle, M. Bender, T. Sowers, P. Tans, J. Butler et al., Atmospheric gas concentrations over the past century measured in air from firn at the South Pole, Nature, vol.383, p.231, 1996.

L. Bazin, A. Landais, B. Lemieux-dudon, H. Toyé-mahamadou-kele, D. Veres et al., An optimized multi-proxy, multisite Antarctic ice and gas orbital chronology (AICC2012): 120-800 ka, Clim. Past, vol.9, pp.1715-1731, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00995643

M. L. Bender, Orbital tuning chronology for the Vostok climate record supported by trapped gas composition, Earth Planet. Sci. Lett, vol.204, pp.980-989, 2002.

M. L. Bender, T. Sowers, J. Barnola, and J. Chappellaz, Changes in the O 2 /N 2 ratio of the atmosphere during recent decades reflected in the composition of air in the firn at Vostok Station, Antarctica, Geophys. Res. Lett, vol.21, pp.189-192, 1994.

B. Bereiter, H. Fischer, J. Schwander, and T. F. Stocker, Diffusive equilibration of N 2 , O 2 and CO 2 mixing ratios in a 1.5-million-years-old ice core, Cryosphere, vol.8, pp.245-256, 2014.

A. Berger, Milankovitch theory and climate, Rev. Geophys, vol.26, pp.624-657, 1988.

M. Bernacki, Y. Chastel, T. Coupez, and R. Logé, Level set framework for the numerical modelling of primary recrystallization in polycrystalline materials, Scr. Mater, vol.58, pp.1129-1132, 2008.
URL : https://hal.archives-ouvertes.fr/hal-00509731

M. Bigler, A. Svensson, E. Kettner, P. Vallelonga, M. E. Nielsen et al., Optimization of high-resolution continuous flow analysis for transient climate signals in ice cores, Envir. Sci. Tech, vol.45, pp.4483-4489, 2011.

N. Boers, M. Ghil, and D. Rousseau, Ocean circulation, ice shelf, and sea ice interactions explain Dansgaard-Oeschger cycles, Proc. Natl. Acad. Sci. USA, 115, E11 005-E11 014, 2018.

V. Boulos, V. Fristot, D. Houzet, L. Salvo, and P. Lhuissier, Investigating performance variations of an optimized GPU-ported granulometry algorithm, Proceedings of the 2012 Conference on Design and Architectures for Signal and Image Processing, pp.1-6, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00787861

M. L. Bouxsein, S. K. Boyd, B. A. Christiansen, R. E. Guldberg, K. J. Jepsen et al., Guidelines for assessment of bone microstructure in rodents using micro-computed tomography, J. Bone Miner. Res, vol.25, pp.1468-1486, 2010.

C. Bréant, P. Martinerie, A. Orsi, L. Arnaud, and A. Landais, Modelling firn thickness evolution during the last deglaciation: constraints on sensitivity to temperature and impurities, Clim. Past, vol.13, pp.833-853, 2017.

E. J. Brook and C. Buizert, Antarctic and global climate history viewed from ice cores, Nature, vol.558, 2018.

E. J. Brook, T. Sowers, and J. Orchardo, Rapid variations in atmospheric methane concentration during the past 110,000 years, Science, vol.273, pp.1087-1091, 1996.

E. J. Brook, S. Harder, J. Severinghaus, E. J. Steig, and C. M. Sucher, On the origin and timing of rapid changes in atmospheric methane during the Last Glacial Period, Global Biogeochemical Cycles, vol.14, pp.559-572, 2000.

J. Bruchon, S. Drapier, and F. Valdivieso, 3D finite element simulation of the matter flow by surface diffusion using a level set method, Int. J. Numer. Methods Eng, vol.86, pp.845-861, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00828629

J. Bruchon, D. Pino-muñoz, F. Valdivieso, and S. Drapier, Finite element simulation of mass transport during sintering of a granular packing. Part I. Surface and lattice diffusions, J. Am. Ceram. Soc, vol.95, pp.2398-2405, 2012.
URL : https://hal.archives-ouvertes.fr/emse-00828886

C. Buizert, P. Martinerie, V. V. Petrenko, J. P. Severinghaus, C. M. Trudinger et al., Gas transport in firn: multiple-tracer characterisation and model intercomparison for NEEM, vol.12, pp.4259-4277, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00843779

C. Buizert, K. M. Cuffey, J. P. Severinghaus, D. Baggenstos, T. J. Fudge et al., The WAIS Divide deep ice core WD2014 chronology-Part 1: methane synchronization (68-31 ka BP) and the gas ageice age difference, Clim. Past, vol.11, pp.153-173, 2015.

A. Burr, C. Ballot, P. Lhuissier, P. Martinerie, C. L. Martin et al., Pore morphology of polar firn around closure revealed by X-ray tomography, Cryosphere, vol.12, pp.2481-2500, 2018.
URL : https://hal.archives-ouvertes.fr/hal-01864373

A. Burr, P. Lhuissier, C. L. Martin, P. , and A. , In situ X-ray tomography densification of firn: The role of mechanics and diffusion processes, Acta Mater, vol.167, pp.210-220, 2019.
URL : https://hal.archives-ouvertes.fr/hal-02067389

N. Caillon, J. P. Severinghaus, J. Jouzel, J. Barnola, J. Kang et al., Timing of Atmospheric CO2 and Antarctic Temperature Changes Across Termination III, vol.299, pp.1728-1731, 2003.

N. Calonne, M. Montagnat, M. Matzl, and M. Schneebeli, The layered evolution of fabric and microstructure of snow at Point Barnola, Earth Planet. Sci. Lett, vol.460, pp.293-301, 2017.
URL : https://hal.archives-ouvertes.fr/hal-01832198

E. Capron, A. Landais, D. Buiron, A. Cauquoin, J. Chappellaz et al., Glacial-interglacial dynamics of Antarctic firn columns: comparison between simulations and ice core air-? 15 N measurements, Clim Past, vol.9, pp.983-999, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00861133

J. Chappellaz, J. Barnola, D. Raynaud, Y. S. Korotkevich, and C. Lorius, Ice-core record of atmospheric methane over the past 160,000 years, Nature, vol.345, pp.127-131, 1990.

J. Chappellaz, C. Stowasser, T. Blunier, D. Baslev-clausen, E. J. Brook et al., High-resolution glacial and deglacial record of atmospheric methane by continuousflow and laser spectrometer analysis along the NEEM ice core, Clim. Past, vol.9, pp.2579-2593, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00996433

P. U. Clark, D. Archer, D. Pollard, J. D. Blum, J. A. Rial et al., The middle Pleistocene transition: characteristics, mechanisms, and implications for long-term changes in atmospheric pCO2, Quat. Sci. Rev, vol.25, pp.3150-3184, 2006.

S. C. Colbeck, Air movement in snow due to windpumping, J. Glaciol, vol.35, pp.209-213, 1989.

S. J. Cooper, A. Bertei, P. R. Shearing, J. A. Kilner, and N. P. Brandon, TauFactor: An opensource application for calculating tortuosity factors from tomographic data, SoftwareX, vol.5, pp.203-210, 2016.

H. Craig, Y. Horibe, and T. Sowers, Gravitational separation of gases and isotopes in polar ice caps, Science, vol.242, pp.1675-1678, 1988.

K. Cuffey and W. S. Paterson, The Physics of Glaciers, 2010.

W. Dansgaard, The Abundance of O18 in Atmospheric Water and Water Vapour, Tellus A, Dyn. Meteorol. Oceanogr, vol.5, pp.461-469, 1953.

W. Dansgaard, S. J. Johnsen, H. B. Clausen, D. Dahl-jensen, N. S. Gundestrup et al., , p.252

C. U. Hvidberg, C. S. Steffensen, J. P. Sveinbjornsdottir, A. E. Jouzel, and J. , Evidence for general instability of past climate from a 250-kyr ice-core record, nature, vol.364, pp.218-220, 1993.
URL : https://hal.archives-ouvertes.fr/hal-01103728

C. Dapogny and P. Frey, Computation of the signed distance function to a discrete contour on adapted triangulation, Calcolo, vol.49, pp.193-219, 2012.

C. Dapogny, C. Dobrzynski, and P. Frey, Three-dimensional adaptive domain remeshing, implicit domain meshing, and applications to free and moving boundary problems, J. Comput. Phys, vol.262, pp.358-378, 2014.
URL : https://hal.archives-ouvertes.fr/hal-00804636

I. Daruka and P. D. Ditlevsen, A conceptual model for glacial cycles and the middle Pleistocene transition, Clim. Dyn, vol.46, pp.29-40, 2016.

R. J. Delmas, J. Ascencio, and M. Legrand, Polar ice evidence that atmospheric CO2 20,000 yr BP was 50% of present, Nature, vol.284, p.155, 1980.

M. Delmotte, J. Chappellaz, E. Brook, P. Yiou, J. Barnola et al., Atmospheric methane during the last four glacial-interglacial cycles: Rapid changes and their link with Antarctic temperature, J. Geophys. Res. Atmos, vol.109, 2004.

E. J. Dlugokencky, R. C. Myers, P. M. Lang, K. A. Masarie, A. M. Crotwell et al., Conversion of NOAA atmospheric dry air CH 4 mole fractions to a gravimetrically prepared standard scale, J. Geophys. Res. Atmos, vol.110, 2005.

M. Doube, M. M. K?osowski, I. Arganda-carreras, F. P. Cordelières, R. P. Dougherty et al., BoneJ: free and extensible bone image analysis in ImageJ, Bone, vol.47, pp.1076-1079, 2010.

G. B. Dreyfus, J. Jouzel, M. L. Bender, A. Landais, V. Masson-delmotte et al., Firn processes and ?15N: potential for a gas-phase climate proxy, Quat. Sci. Rev, vol.29, pp.28-42, 2010.

P. Duval, M. F. Ashby, A. , and I. , Rate-controlling processes in the creep of polycrystalline ice, J. Phys. Chem, vol.87, pp.4066-4074, 1983.

A. Dällenbach, T. Blunier, J. Flückiger, B. Stauffer, J. Chappellaz et al., Changes in the atmospheric CH4 gradient between Greenland and Antarctica during the Last Glacial and the transition to the Holocene, Geophys. Res. Lett, vol.27, pp.1005-1008, 2000.

I. G. Enting, Statistics of firn closure: a simulation study, Journal of Glaciology, vol.39, pp.133-142, 1993.

A. Epica-community-members, L. Barbante, C. Barnes, P. R. Barnola, J. M. Bigler et al., Eight glacial cycles from an Antarctic ice core, Nature, vol.429, pp.623-628, 2004.

D. M. Etheridge, G. I. Pearman, and P. J. Fraser, Changes in tropospheric methane between 1841 and 1978 from a high accumulation-rate Antarctic ice core, Tellus B Chem. Phys. Meteorol, vol.44, pp.282-294, 1992.

A. Fabre, J. Barnola, L. Arnaud, and J. Chappellaz, Determination of gas diffusivity in polar firn: comparison between experimental measurements and inverse modeling, Geophys. Res. Lett, vol.27, pp.557-560, 2000.

X. Faïn, J. Chappellaz, R. H. Rhodes, C. Stowasser, T. Blunier et al., High resolution measurements of carbon monoxide along a late Holocene Greenland ice core: evidence for in situ production, Clim. Past, vol.10, pp.987-1000, 2014.

H. Fischer, J. Severinghaus, E. Brook, E. W. Wolff, M. Albert et al., Where to find 1.5 million yr old ice for the IPICS "Oldest-Ice" ice core, Clim. Past, vol.9, pp.2489-2505, 2013.

K. Fourteau, X. Faïn, P. Martinerie, A. Landais, A. A. Ekaykin et al., Analytical constraints on layered gas trapping and smoothing of atmospheric variability in ice under low-accumulation conditions, Clim. Past, vol.13, pp.1815-1830, 2017.

J. Freitag, U. Dobrindt, and J. Kipfstuhl, A new method for predicting transport properties of polar firn with respect to gases on the pore-space scale, Ann. Glaciol, vol.35, pp.538-544, 2002.

J. Freitag, F. Wilhelms, and S. Kipfstuhl, Microstructure-dependent densification of polar firn derived from X-ray microtomography, J. Glaciol, vol.50, pp.243-250, 2004.

J. Freitag, S. Kipfstuhl, T. Laepple, and F. Wilhelms, Impurity-controlled densification: a new model for stratified polar firn, J. Glaciol, vol.59, pp.1163-1169, 2013.

S. Fujita, J. Okuyama, A. Hori, and T. Hondoh, Metamorphism of stratified firn at Dome Fuji, Antarctica: A mechanism for local insolation modulation of gas transport conditions during bubble close off, J. Geophys. Res. Earth Surf, vol.114, p.3023, 2009.

S. Fujita, M. Hirabayashi, K. Goto-azuma, R. Dallmayr, K. Satow et al., Densification of layered firn of the ice sheet at NEEM, Greenland, J. Glaciol, vol.60, pp.905-921, 2014.

S. Fujita, K. Goto-azuma, M. Hirabayashi, A. Hori, Y. Iizuka et al., Densification of layered firn in the ice sheet at Dome Fuji, Antarctica, J. Glaciol, vol.62, pp.103-123, 2016.

E. Gautier, J. Savarino, J. Erbland, A. Lanciki, and P. Possenti, Variability of sulfate signal in ice core records based on five replicate cores, Clim. Past, vol.12, pp.103-113, 2016.
URL : https://hal.archives-ouvertes.fr/insu-01351966

N. Gedney, P. Cox, and C. Huntingford, Climate feedback from wetland methane emissions, Geophys. Res. Lett, vol.31, 2004.

G. Genthon, J. Barnola, D. Raynaud, C. Lorius, J. Jouzel et al., Vostok ice core: climatic response to CO2 and orbital forcing changes over the last climatic cycle, Nature, vol.329, p.414, 1987.

F. Gibou, R. Fedkiw, and S. Osher, A review of level-set methods and some recent applications, J. Comput. Phys, vol.353, pp.82-109, 2018.

C. Goujon, J. Barnola, and C. Ritz, Modeling the densification of polar firn including heat diffusion: application to close-off characteristics and gas isotopic fractionation for Antarctica and Greenland sites, J. Geophys. Res. Atmos, vol.108, p.4792, 2003.

S. A. Gregory, M. R. Albert, and I. Baker, Impact of physical properties and accumulation rate on pore close-off in layered firn, Cryosphere, vol.8, pp.91-105, 2014.

P. Hagenmuller, G. Chambon, B. Lesaffre, F. Flin, N. Calonne et al., Energybased binary segmentation of snow microtomographic images, 1st International Conference on Tomography of Materials and Structures (ICTMS, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00863099

C. Hendy and A. Wilson, Palaeoclimatic data from speleothems, Nature, vol.219, p.48, 1968.

M. M. Herron and C. C. Langway, Firn Densification: An Empirical Model, J. Glaciol, vol.25, pp.373-385, 1980.

T. Hildebrand and P. Rüegsegger, Quantification of Bone Microarchitecture with the Structure Model Index, Comput. Methods Biomech. Biomed. Eng, vol.1, pp.15-23, 1997.

P. Hobbs, Ice Physics, 1974.

J. Höhle and M. Höhle, Accuracy assessment of digital elevation models by means of robust statistical methods, ISPRS J. Photogramm. Remote Sens, vol.64, pp.398-406, 2009.

P. O. Hopcroft, P. J. Valdes, and D. J. Beerling, Simulating idealized Dansgaard-Oeschger events and their potential impacts on the global methane cycle, Quat. Sci. Rev, vol.30, pp.3258-3268, 2011.

M. W. Hörhold, S. Kipfstuhl, F. Wilhelms, J. Freitag, and A. Frenzel, The densification of layered polar firn, J. Geophys. Res. Earth Surf, vol.116, 2011.

M. W. Hörhold, T. Laepple, J. Freitag, M. Bigler, H. Fischer et al., On the impact of impurities on the densification of polar firn, Earth Planet. Sci. Lett, vol.325, pp.93-99, 2012.

C. Huber, U. Beyerle, M. Leuenberger, J. Schwander, R. Kipfer et al., Evidence for molecular size dependent gas fractionation in firn air derived from noble gases, oxygen, and nitrogen measurements, Earth Planet. Sci. Lett, vol.243, pp.61-73, 2006.

C. Huber, M. Leuenberger, R. Spahni, J. Flückiger, J. Schwander et al., Isotope calibrated Greenland temperature record over Marine Isotope Stage 3 and its relation to CH4, Earth Planet. Sci. Lett, vol.243, pp.504-519, 2006.

M. A. Hutterli, M. Schneebeli, J. Freitag, J. Kipfstuhl, and R. Röthlisberger, Impact of local insolation on snow metamorphism and ice core records, Physics of Ice Core Records II : Papers collected after the 2nd International Workshop on Physics of Ice Core Records, vol.68, pp.223-232, 2009.

, Contribution of Working Groups I, Synthesis Report, 2014.

S. J. Johnsen, W. Dansgaard, and J. White, The origin of Arctic precipitation under present and glacial conditions, Tellus B: Chem. Phys. Meteorol, vol.41, pp.452-468, 1989.

S. Jones and J. Glen, The effect of dissolved impurities on the mechanical properties of ice crystals, Philos. Mag. J. Theor. Exp. Appl. Phys, vol.19, pp.13-24, 1969.

S. J. Jones, Softening of ice crystals by dissolved fluoride ions, Phys. Lett, vol.25, pp.366-367, 1967.

F. Joos and R. Spahni, Rates of change in natural and anthropogenic radiative forcing over the past 20,000 years, Proc. Natl. Acad. Sci. USA, 105, pp.1425-1430, 2008.

J. Jouzel, V. Masson-delmotte, O. Cattani, G. Dreyfus, S. Falourd et al., Orbital and millennial antarctic climate variability over the past 800,000 years, Science, vol.317, pp.793-796, 2007.
URL : https://hal.archives-ouvertes.fr/insu-00376332

K. Kawamura, F. Parrenin, L. Lisiecki, R. Uemura, F. Vimeux et al., Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years, Nature, vol.448, p.912, 2007.
URL : https://hal.archives-ouvertes.fr/insu-00376337

P. Köhler, R. Bintanja, H. Fischer, F. Joos, R. Knutti et al., What caused Earth's temperature variations during the last 800,000 years? Data-based evidence on radiative forcing and constraints on climate sensitivity, Quat. Sci. Rev, vol.29, pp.129-145, 2010.

P. Köhler, G. Knorr, D. Buiron, A. Lourantou, and J. Chappellaz, Abrupt rise in atmospheric CO 2 at the onset of the Bølling/Allerød: in-situ ice core data versus true atmospheric signal, Clim. Past, vol.7, pp.473-486, 2011.

P. Köhler, C. Völker, G. Knorr, and E. Bard, High latitude impacts on deglacial CO 2 : southern ocean westerly winds and northern hemisphere permafrost thawing, Nova. Act. Lc, vol.121, pp.135-140, 2015.

Q. Krol and H. Löwe, Relating optical and microwave grain metrics of snow: the relevance of grain shape, Cryosphere, vol.10, pp.2847-2863, 2016.

F. Lambert, M. Bigler, J. P. Steffensen, M. Hutterli, and H. Fischer, Centennial mineral dust variability in high-resolution ice core data from Dome C, Antarctica, Clim. Past, vol.8, pp.609-623, 2012.

A. Landais, N. Caillon, J. Severinghaus, J. Barnola, C. Goujon et al.,

V. Delmotte, Analyse isotopique de l'air piégé dans la glace pour quantifier les variations de température, C.R. Geosci, vol.336, pp.963-970, 2004.

A. Landais, J. Barnola, K. Kawamura, N. Caillon, M. Delmotte et al., Firn-air ?15N in modern polar sites and glacial-interglacial ice: a model-data mismatch during glacial periods in Antarctica?, Quat. Sci. Rev, vol.25, pp.49-62, 2006.
URL : https://hal.archives-ouvertes.fr/insu-00375513

A. Landais, V. Masson-delmotte, B. Stenni, E. Selmo, D. Roche et al., A review of the bipolar see-saw from synchronized and high resolution ice core water stable isotope records from Greenland and East Antarctica, Quat. Sci. Rev, vol.114, pp.18-32, 2015.
URL : https://hal.archives-ouvertes.fr/hal-01575260

S. Lauritzen, High-Resolution Paleotemperature Proxy Record for the Last Interglaciation Based on Norwegian Speleothems, Quat. Res, vol.43, pp.133-146, 1995.

M. Legrand and P. Mayewski, Glaciochemistry of polar ice cores: A review, Rev. Geophys, vol.35, pp.219-243, 1997.
URL : https://hal.archives-ouvertes.fr/insu-00502145

D. R. Lide, CRC Handbook of Chemistry and Physics, 2005.

V. Lipenkov, F. Candaudap, J. Ravoire, E. Dulac, and D. Raynaud, A new device for the measurement of air content in polar ice, J. Glaciol, vol.41, pp.423-429, 1995.

V. Y. Lipenkov, Air bubbles and air-hydrate crystals in the Vostok ice core, in: Phys. Ice Core Rec, pp.327-358, 2000.

V. Y. Lipenkov, A. N. Salamatin, and P. Duval, Bubbly-ice densification in ice sheets: II. Applications, J. Glaciol, vol.43, pp.397-407, 1997.

V. Y. Lipenkov, D. Raynaud, M. Loutre, and P. Duval, On the potential of coupling air content and O2/N2 from trapped air for establishing an ice core chronology tuned on local insolation, Quat. Sci. Rev, vol.30, pp.3280-3289, 2011.

L. Lisiecki and M. E. Raymo, A Pliocene-Pleistocene stack of 57 globally distributed benthic ?18O records, Paleoceanograph, vol.20, 2005.
URL : https://hal.archives-ouvertes.fr/hal-01103826

L. Loulergue, A. Schilt, R. Spahni, V. Masson-delmotte, T. Blunier et al., Orbital and millennialscale features of atmospheric CH 4 over the past 800,000 years, Nature, vol.453, pp.383-386, 2008.
URL : https://hal.archives-ouvertes.fr/insu-00379657

J. M. Lundin, C. M. Stevens, R. Arthern, C. Buizert, A. Orsi et al., Firn Model Intercomparison Experiment (FirnMICE), vol.63, pp.401-422, 2017.

D. Lüthi, M. L. Floch, B. Bereiter, T. Blunier, J. Barnola et al., High-resolution carbon dioxide concentration record 650,000-800,000 years before present, Nature, vol.453, pp.379-382, 2008.

N. Maeno and T. Ebinuma, Pressure sintering of ice and its implication to the densification of snow at polar glaciers and ice sheets, J. Phys. Chem, vol.87, pp.4103-4110, 1983.

S. A. Marcott, T. K. Bauska, C. Buizert, E. J. Steig, J. L. Rosen et al., Centennial-scale changes in the global carbon cycle during the last deglaciation, Nature, vol.514, pp.616-619, 2014.

C. Martín and G. H. Gudmundsson, Effects of nonlinear rheology, temperature and anisotropy on the relationship between age and depth at ice divides, Cryosphere, vol.6, pp.1221-1229, 2012.

P. Martinerie, V. Y. Lipenkov, and D. Raynaud, Correction of air-content measurements in polar ice for the effect of cut bubbles at the surface of the sample, J. Glaciol, vol.36, pp.299-303, 1990.

P. Martinerie, D. Raynaud, D. M. Etheridge, J. Barnola, and D. Mazaudier, Physical and climatic parameters which influence the air content in polar ice, Earth Planet. Sc. Lett, vol.112, pp.1-13, 1992.

P. Martinerie, V. Y. Lipenkov, D. Raynaud, J. Chappellaz, N. Barkov et al., Air content paleo record in the Vostok ice core (Antarctica): A mixed record of climatic and glaciological parameters, J. Geophys. Res. Atmos, vol.99, pp.565-575, 1994.

V. Masson-delmotte, M. Schulz, A. Abe-ouchi, J. Beer, A. Ganopolski et al., Information from paleoclimate archives, in: Climate change 2013: the physical science basis. Contribution of working group I to the fifth assessment report of the Intergovernmental Panel on Climate Change, pp.383-464, 2013.

E. W. Mayer, D. R. Blake, S. C. Tyler, Y. Makide, D. C. Montague et al., Methane: Interhemispheric concentration gradient and atmospheric residence time, Proc. Natl. Acad. Sci. USA, vol.79, pp.1366-1370, 1982.

F. Mcdermott, Palaeo-climate reconstruction from stable isotope variations in speleothems: a review, Quat. Sci. Rev, vol.23, pp.901-918, 2004.

F. Mees, R. Swennen, M. V. Geet, and P. Jacobs, Applications of X-ray computed tomography in the geosciences, Geol. Soc. Lond. Special Publ, vol.215, pp.1-6, 2003.

M. M. Milankovitch, Théorie Mathématique des Phenomenes Thermiques Produits par la Radiation Solaire, Académie Yougoslave des Sciences et des Arts de Zagreb, 1920.

L. Mitchell, E. Brook, J. E. Lee, C. Buizert, and T. Sowers, Constraints on the Late Holocene Anthropogenic Contribution to the Atmospheric Methane Budget, vol.342, pp.964-966, 2013.

L. E. Mitchell, E. J. Brook, T. Sowers, J. R. Mcconnell, T. et al., Multidecadal variability of atmospheric methane, J. Geophys. Res. Biogeosci, vol.116, pp.1000-1800, 2007.

L. E. Mitchell, C. Buizert, E. J. Brook, D. J. Breton, J. Fegyveresi et al., Observing and modeling the influence of layering on bubble trapping in polar firn, J. Geophys. Res. Atmos, vol.120, pp.2558-2574, 2015.
URL : https://hal.archives-ouvertes.fr/hal-01806235

J. Morville, S. Kassi, M. Chenevier, and D. Romanini, Fast, low-noise, mode-by-mode, cavity-enhanced absorption spectroscopy by diode-laser self-locking, Appl. Phys. B-Lasers O, vol.80, pp.1027-1038, 2005.
URL : https://hal.archives-ouvertes.fr/hal-01103503

R. A. Muller and G. J. Macdonald, Glacial cycles and astronomical forcing, vol.277, pp.215-218, 1997.

T. Nakamura and S. Jones, Softening effect of dissolved hydrogen chloride in ice crystals, Scr. Metall, vol.4, pp.123-126, 1970.

M. Newman and G. Barkema, Monte carlo methods in statistical physics chapter, 1999.

E. Olsson and G. Kreiss, A conservative level set method for two phase flow, J. Comput. Phys, vol.210, pp.225-246, 2005.

E. Olsson, G. Kreiss, and S. Zahedi, A conservative level set method for two phase flow II, J. Comput. Phys, vol.225, pp.785-807, 2007.

A. J. Orsi, B. D. Cornuelle, and J. P. Severinghaus, Magnitude and temporal evolution of Dansgaard-Oeschger event 8 abrupt temperature change inferred from nitrogen and argon isotopes in GISP2 ice using a new least-squares inversion, Earth Planet. Sc. Lett, vol.395, pp.81-90, 2014.

S. Osher and R. P. Fedkiw, Level Set Methods: An Overview and Some Recent Results, J. Comput. Phys, vol.169, pp.463-502, 2001.

S. Osher and J. A. Sethian, Fronts propagating with curvature-dependent speed: Algorithms based on Hamilton-Jacobi formulations, J. Comput. Phys, vol.79, pp.12-49, 1988.

F. Parrenin, J. Petit, V. Masson-delmotte, E. Wolff, I. Basile-doelsch et al., Volcanic synchronisation between the EPICA Dome C and Vostok ice cores (Antarctica) 0-145 kyr BP, Clim. Past, vol.8, pp.1031-1045, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00725778

F. Parrenin, V. Masson-delmotte, P. Köhler, D. Raynaud, D. Paillard et al., Synchronous Change of Atmospheric CO2 and Antarctic Temperature During the Last Deglacial Warming, Science, vol.339, pp.1060-1063, 2013.
URL : https://hal.archives-ouvertes.fr/cea-00862616

O. Passalacqua, M. Cavitte, O. Gagliardini, F. Gillet-chaulet, F. Parrenin et al., Brief communication: Candidate sites of 1.5 Myr old ice 37 km southwest of the

E. Dome-c-summit and . Antarctica, Cryosphere, vol.12, pp.2167-2174, 2018.

M. Peternell, D. Russell-head, W. , and C. , A technique for recording polycrystalline structure and orientation during in situ deformation cycles of rock analogues using an automated fabric analyser, J. Microsc. Oxford, vol.242, pp.181-188, 2010.

J. R. Petit, J. Jouzel, D. Raynaud, N. I. Barkov, J. Barnola et al., Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Nature, vol.399, pp.429-436, 1999.
URL : https://hal.archives-ouvertes.fr/hal-00756651

V. V. Petrenko, P. Martinerie, P. Novelli, D. M. Etheridge, I. Levin et al., A 60 yr record of atmospheric carbon monoxide reconstructed from Greenland firn air, Atmos. Chem. Phys, vol.13, pp.7567-7585, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00931570

P. Pimienta and P. Duval, Rate controlling processes in the creep of polar glacier ice, J. Phys Colloques, vol.48, pp.1-243, 1987.
URL : https://hal.archives-ouvertes.fr/jpa-00226280

C. F. Raymond, Deformation in the Vicinity of Ice Divides, J. Glaciol, vol.29, pp.357-373, 1983.

D. Raynaud and B. Lebel, Total gas content and surface elevation of polar ice sheets, Nature, vol.281, p.289, 1979.

D. Raynaud, R. Delmas, J. Ascencio, and M. Legrand, Gas Extraction From Polar Ice Cores: A Critical Issue For Studying The Evolution of Atmospheric CO2 and Ice-Sheet Surface Elevation, Ann. Glaciol, vol.3, pp.265-268, 1982.

D. Raynaud, J. Chappellaz, J. Barnola, Y. S. Korotkevich, and C. Lorius, Climatic and CH4 cycle implications of glacial-interglacial CH4 change in the Vostok ice core, Nature, vol.333, p.655, 1988.

D. Raynaud, V. Lipenkov, B. Lemieux-dudon, P. Duval, M. Loutre et al., The local insolation signature of air content in Antarctic ice. A new step toward an absolute dating of ice records, Earth Planet. Sci. Lett, vol.261, pp.337-349, 2007.
URL : https://hal.archives-ouvertes.fr/insu-00377262

R. H. Rhodes, X. Faïn, C. Stowasser, T. Blunier, J. Chappellaz et al., Continuous methane measurements from a late Holocene Greenland ice core: atmospheric and in-situ signals, Earth Planet. Sc. Lett, vol.368, pp.9-19, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00996075

R. H. Rhodes, E. J. Brook, J. C. Chiang, T. Blunier, O. J. Maselli et al., Enhanced tropical methane production in response to iceberg discharge in the North Atlantic, Science, vol.348, pp.1016-1019, 2015.
URL : https://hal.archives-ouvertes.fr/hal-02011689

R. H. Rhodes, X. Faïn, E. J. Brook, J. R. Mcconnell, O. J. Maselli et al., Local artifacts in ice core methane records caused by layered bubble trapping and in situ production: a multi-site investigation, Clim. Past, vol.12, pp.1061-1077, 2016.
URL : https://hal.archives-ouvertes.fr/insu-01387742

E. L. Ritman, Micro-Computed Tomography-Current Status and Developments, Annu. Rev. Biomed. Eng, vol.6, pp.185-208, 2004.

D. Romanini, M. Chenevier, S. Kassi, M. Schmidt, C. Valant et al., Optical-feedback cavity-enhanced absorption: a compact spectrometer for real-time measurement of atmospheric methane, Appl. Phys. B-Lasers O, vol.83, pp.659-667, 2006.
URL : https://hal.archives-ouvertes.fr/hal-01103500

V. Rommelaere, L. Arnaud, and J. Barnola, Reconstructing recent atmospheric trace gas concentrations from polar firn and bubbly ice data by inverse methods, J. Geophys

. Res and . Atmos, , vol.102, p.83, 1997.

R. G. Rothwell and F. R. Rack, New techniques in sediment core analysis: an introduction, Geol. Soc. Lond. Special Publ, vol.267, pp.1-29, 2006.

P. J. Rousseeuw and M. Hubert, Robust statistics for outlier detection, Wires Data Min. Knowl. Discov, vol.1, pp.73-79, 2011.

A. N. Salamatin, V. Y. Lipenkov, J. M. Barnola, A. Hori, P. Duval et al., Snow/-firn densification in polar ice sheets, Low Temperature Science, vol.68, pp.195-222, 2009.

P. L. Salmon, C. Ohlsson, S. J. Shefelbine, and M. Doube, Structure Model Index Does Not Measure Rods and Plates in Trabecular Bone, Front. Endocrinol, vol.6, p.162, 2015.

C. F. Schaller, J. Freitag, and O. Eisen, Critical porosity of gas enclosure in polar firn independent of climate, Clim. Past, vol.13, pp.1685-1693, 2017.

J. Schmitt, R. Schneider, and H. Fischer, A sublimation technique for high-precision measurements of ? 13 CO 2 and mixing ratios of CO 2 and N 2 O from air trapped in ice cores, Atmos. Meas. Tech, vol.4, pp.1445-1461, 2011.

E. M. Schulson and P. Duval, Creep and Fracture of Ice, 2009.
URL : https://hal.archives-ouvertes.fr/insu-00421610

J. Schwander, The transformation of snow to ice and the occlusion of gases, in: The environmental record in glaciers and ice sheets, pp.53-67, 1989.

J. Schwander and B. Stauffer, Age difference between polar ice and the air trapped in its bubbles, Nature, vol.311, pp.45-47, 1984.

J. Schwander, B. Stauffer, and A. Sigg, Air mixing in firn and the age of the air at pore close-off, Ann. Glaciol, vol.10, pp.141-145, 1988.

J. Schwander, J. Barnola, C. Andrié, M. Leuenberger, A. Ludin et al., The age of the air in the firn and the ice at Summit, Greenland, J. Geophys. Res. Atmos, vol.98, pp.2831-2838, 1993.

J. P. Severinghaus and M. O. Battle, Fractionation of gases in polar ice during bubble closeoff: New constraints from firn air Ne, Kr and Xe observations, Earth Planet. Sci. Lett, vol.244, pp.474-500, 2006.

J. P. Severinghaus, M. R. Albert, Z. R. Courville, M. A. Fahnestock, K. Kawamura et al.,

. Antarctica, Earth Planet. Sci. Lett, vol.293, pp.359-367, 2010.

N. Shackleton and N. Opdyke, Oxygen-Isotope and Paleomagnetic Stratigraphy of Pacific Core V28-239 Late Pliocene to Latest Pleistocene, Geol. Soc. Am, vol.145, p.449, 1976.

J. D. Shakun, P. U. Clark, F. He, S. A. Marcott, A. C. Mix et al., Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation, Nature, vol.484, pp.49-54, 2012.

S. Shieh and J. W. Evans, The stability of cylindrical voids and of cylinders subject to closure by viscous flow or evaporation/condensation, J. Appl. Phys, vol.70, pp.2968-2972, 1991.

D. T. Shindell, B. P. Walter, and G. Faluvegi, Impacts of climate change on methane emissions from wetlands, Geophys. Res. Lett, vol.31, 2004.

R. H. Shumway and Z. A. Der, Deconvolution of Multiple Time Series, vol.27, pp.385-393, 1985.

T. Sowers, M. Bender, D. Raynaud, and Y. S. Korotkevich, ?15N of N2 in air trapped in polar ice: A tracer of gas transport in the firn and a possible constraint on ice age-gas age differences, J. Geophy. Res. Atmos, vol.97, pp.683-698, 1992.

R. Spahni, J. Schwander, J. Flückiger, B. Stauffer, J. Chappellaz et al., The attenuation of fast atmospheric CH 4 variations recorded in polar ice cores, Geophys. Res. Lett, vol.30, 2003.

B. Stauffer, G. Fischer, A. Neftel, and H. Oeschger, Increase of atmospheric methane recorded in antarctic ice core, Science, vol.229, pp.1386-1388, 1985.

B. Stauffer, J. Schwander, and H. Oeschger, Enclosure of air during metamorphosis of dry firn to ice, Ann. Glaciol, vol.6, pp.108-112, 1985.

R. Storn and K. Price, Differential evolution -A simple and efficient heuristic for global optimization over continuous spaces, J. Global. Optim, vol.11, pp.341-359, 1997.

C. Stowasser, C. Buizert, V. Gkinis, J. Chappellaz, S. Schüpbach et al., Continuous measurements of methane mixing ratios from ice cores, Atmos. Meas. Tech, vol.5, pp.999-1013, 2012.
URL : https://hal.archives-ouvertes.fr/insu-00844086

J. Sutter, H. Fischer, K. Grosfeld, N. B. Karlsson, T. Kleiner et al., Modelling the Antarctic Ice Sheet across the mid-Pleistocene transition -implications for Oldest Ice, Cryosphere, vol.13, pp.2023-2041, 2019.

J. I. Svendsen, H. Alexanderson, V. I. Astakhov, I. Demidov, J. A. Dowdeswell et al., Late Quaternary ice sheet history of northern Eurasia, Quat. Sci. Rev, vol.23, pp.1229-1271, 2004.

E. R. Thomas, E. W. Wolff, R. Mulvaney, J. P. Steffensen, S. J. Johnsen et al., The 8.2 ka event from Greenland ice cores, Quat. Sci. Rev, vol.26, pp.70-81, 2007.
URL : https://hal.archives-ouvertes.fr/hal-01990608

C. M. Trudinger, I. G. Enting, D. M. Etheridge, R. J. Francey, V. A. Levchenko et al., Modeling air movement and bubble trapping in firn, J. Geophys. Res. Atmos, vol.102, pp.6747-6763, 1997.

K. J. Ueltzhöffer, V. Bendel, J. Freitag, S. Kipfstuhl, D. Wagenbach et al., Distribution of air bubbles in the EDML and EDC (Antarctica) ice cores, using a new method of automatic image analysis, J. Glaciol, vol.56, pp.339-348, 2010.

B. Van-liefferinge and F. Pattyn, Using ice-flow models to evaluate potential sites of million year-old ice in Antarctica, Clim. Past, vol.9, pp.2335-2345, 2013.

B. Van-liefferinge, F. Pattyn, M. G. Cavitte, N. B. Karlsson, D. A. Young et al., Promising Oldest Ice sites in East Antarctica based on thermodynamical modelling, Cryosphere, vol.12, pp.2773-2787, 2018.

N. Vasiliev, P. Talalay, N. Bobin, V. Chistyakov, V. Zubkov et al., Deep drilling at Vostok station, Antarctica: history and recent events, Ann. Glaciol, vol.47, pp.10-23, 2007.

D. Veres, L. Bazin, A. Landais, H. Toyé-mahamadou-kele, B. Lemieux-dudon et al., The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years, Clim. Past, vol.9, pp.1733-1748, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00995618

D. Wilkinson and M. Ashby, Pressure sintering by power law creep, Acta Metall, vol.23, pp.1277-1285, 1975.

M. Willeit, A. Ganopolski, R. Calov, and V. Brovkin, Mid-Pleistocene transition in glacial cycles explained by declining CO2 and regolith removal, Sci. Adv, vol.5, p.7337, 2019.

A. T. Wilson and A. Long, New approaches to CO2 analysis in polar ice cores, J. Geophys. Res. Oceans, vol.102, pp.601-627, 1997.

C. J. Wilson, D. S. Russell-head, and H. M. Sim, The application of an automated fabric analyzer system to the textural evolution of folded ice layers in shear zones, Ann. Glaciol, vol.37, pp.7-17, 2003.

E. Witrant and P. Martinerie, Input Estimation from Sparse Measurements in LPV Systems and Isotopic Ratios in Polar Firns, 5th IFAC Symposium on System Structure and Control, vol.46, pp.659-664, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00931664

E. Witrant, P. Martinerie, C. Hogan, J. C. Laube, K. Kawamura et al., A new multigas constrained model of trace gas non-homogeneous transport in firn: evaluation and behaviour at eleven polar sites, Atmos. Chem. Phys, vol.12, p.483, 2012.

L. Y. Yeung, L. T. Murray, P. Martinerie, E. Witrant, H. Hu et al., Isotopic constraint on the increase in tropospheric ozone in the twentieth century, Nature
URL : https://hal.archives-ouvertes.fr/hal-02179376

L. Zhao, X. Bai, T. Li, W. , and J. , Improved conservative level set method, Int. J. Numer. Methods Fluids, vol.75, pp.575-590, 2014.

L. Zhao, J. Mao, X. Bai, X. Liu, T. Li et al., Finite element implementation of an improved conservative level set method for two-phase flow, Comput. Fluids, vol.100, pp.138-154, 2014.

L. Zhao, J. Mao, X. Liu, X. Bai, W. et al., Improved conservative level set method for free surface flow simulation, J. Hydrodyn, vol.26, issue.14, pp.60035-60039, 2014.