Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 3 1 2007 10.5194/cpd-3-19-2007 http://www.clim-past-discuss.net/3/19/2007/ http://www.clim-past-discuss.net/3/19/2007/cpd-3-19-2007.html http://www.clim-past-discuss.net/3/19/2007/cpd-3-19-2007.pdf 19 61 2007-01-16 Ice flow modelling at EPICA Dome C and Dome Fuji, East Antarctica F. Parrenin parrenin@ujf-grenoble.fr G. Dreyfus G. Durand S. Fujita O. Gagliardini F. Gillet J. Jouzel K. Kawamura N. Lhomme V. Masson-Delmotte C. Ritz J. Schwander H. Shoji R. Uemura O. Watanabe N. Yoshida Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS and Joseph Fourier University, Grenoble, France Laboratoire des Sciences du Climat et de l'Environnement, Gif-Sur-Yvette, France Niels Bohr Institute for Astronomy, Physics and Geophysics, Copenhagen, Denmark National Institute of Polar Research, Research Organization of Information and Systems (ROIS), Tokyo, Japan Center for Atmospheric and Oceanic Studies Graduate School of Science, Tohoku University, Sendai, Japan Physics Institute, University of Bern, Switzerland New Energy Resources Research Center, Kitami Institute of Technology, Kitami, Japan Frontier Collaborative Research Center, Yokohama, Japan 1-D ice flow models are used to construct the age scales at the Dome C and Dome Fuji drilling sites (East Antarctica). The poorly constrained glaciological parameters at each site are recovered by fitting independent age markers identified on each core. We reconstruct past accumulation rates, that are larger than those modelled using the classical vapour saturation pressure relationship during glacial periods by up to a factor 1.5. During the Early Holocene, changes in reconstructed accumulation are not linearly related to changes in ice isotopic composition. A simple model of past elevation changes is developed and shows an amplitude variation of 110–120 m at both sites. We suggest that there is basal melting at Dome C (0.56±0.19 mm/yr). The reconstructed velocity profile is highly non linear at both sites, which suggests complex ice flow effects. This induces a non linear thinning function in both drilling sites, which is also characterized by bumps corresponding to variations in surface elevation with time. Andersen, K. K., Svensson, A., Johnsen, S. J., Rasmussen, S. O., Bigler, M., Röthlisberger, R., Ruth, U., Siggaard-Andersen, M.-L., Steffensen, J. P., Dahl-Jensen, D., Vinther, B. M., and Clausen, H. B: The Greenland Ice Core Chronology 2005, 15–42 kyr. Part 1: Constructing the time scale, Quat. Sci. Rev., in press, 2007. Bassinot, F. C., Labeyrie, L. D., Vincent, E., Quidelleur, X., Shackleton, N. J., and Lancelot, Y: The astronomical theory of climate and the age of the Brunhes-Matuyama magnetic reversal, Earth Planet. Sci. Lett., 126(1–3), 91–108, 1994. Bintanja, R., Van de Wal, R. S., and Oerlemans, J: Modelled atmospheric temperatures and global sea levels over the past million years, Nature, 437, 125–128, 2005. Blunier, T. and Brook, E. J: Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period, Science, 291(5501), 109–112, 2001. Castellano, E., Becagli, S., Hansson, M., Hutterli, M., Petit, J. R., Rampino, M. R., Severi, M., Steffensen, J. P., Traversi, R., and Udisti, R: Holocene volcanic history as recorded in the sulfate stratigraphy of the European Project for Ice Coring in Antarctica Dome C (EDC96) ice core, J. Geophys. Res., 116, D06114, doi:10.1029/2004JD005259, 2005. Connolley, W. M: The Antarctic temperature inversion, Int. J. Climatol., 16, 1333–1342, 1996. Conway, H., Hall, B. L., Denton, G. H., Gades, A. M., and Waddington, E. D: Past and Future Grounding-Line Retreat of the West Antarctic Ice Sheet, Science, 286, 280–283, 1999. EPICA community members: 8 glacial cycles from an Antarctic ice core, Nature, 429, 623–628, 2004. Forieri, A., Zuccoli, L., Bini, A., Zirizzotti, A., Remy, F., and Tabacco, I. E: New bedrock map of Dome C, Antarctica, and morphostructural interpretation of the area, Ann. Glaciol., 39, 321–325, 2004. Frezzotti, M., Pourchet, M., Flora, O., Gandolfi, S., Gay, M., Urbini, S., Vincent, C., Becagli, S., Gragnani, R., Proposito, M., Severi, M., Traversi, R., Udisti, R., and Fily, M: Spatial and temporal variability of snow accumulation in East Antarctica from traverse data, J. Glaciol., 51(172), 113–124, 2005. Fujita, S., Maeno, H., and Matsuoka, K: Radio wave depolarization and scattering within ice sheets: A matrix based model to link radar and ice core measurements and its application, J. Glaciol., 52(178), 407–424, 2006. Fujita, S., Maeno, H., Uratsuka, S., Furukawa, T., Mae, S., Fujii, Y., and Watanabe, O: Nature of radio-echo layering in the Antarctic ice sheet detected by a two-frequency experiment, J. Geophys. Res., 104(B6), 13 013–13 024, 1999. Fujita, S., Kawada, K., and Fujii, Y: Glaciological data collected by the 37th JapaneseAntarctic Research Expedition during 1996–1997. Data Reports Glaciology, 27, JARE, 1998. Hondoh, T., Shoji, H., Watanabe, O., Salamatin, A. N., and Lipenkov, V. Y: Depth-age scale and temperature prediction at Dome Fuji station, East Antarctica, Ann. Glaciol., 35, 384–390, 2002. Hondoh, T., Shoji, H., Watanabe, O., Tsyganova, E., Salamatin, A. N., and Lipenkov, W. Y: Average time scale for Dome Fuji ice core, East Antarctica, Polar Meteorol. Glaciol., 18, 1–18, 2004. Johnsen, S. J., Dahl-Jensen, D., Dansgaard, W., and Gundestrup, N. S: Greenland temperatures derived from GRIP bore hole temperature and ice core isotope profiles, Tellus, 47b(5), 624–629, 1995. Johnsen, S., Dahl-Jensen, D., Gundestrup, N., Steffensen, J., Clausen, H., Miller, H., Masson-Delmotte, V., Sveinbjornsdottir, A., and White, J: Oxygen isotope and palaeotemperaturevrecords from six Greenland ice-core stations: Camp Century, Dye-3, GRIP, GISP2, Renland and NorthGRIP, J. Quat. Sci., 16, 299–307, 2001. Johnsen, S. J. and Dansgaard, W: On flow model dating of stable isotope records from Greenland ice cores, in: The Last Deglaciation: Absolute and Radiocarbon Chronologies, edited by: Bard, E. and Broecker, W., Springler Verlag, Berlin Heidelberg, 1992. Krinner, G. and Genthon, C: Altitude dependence of the surface climate over the ice sheets, Geophys. Res. Lett., 26, 2227–2230, 1999. Landais, A., Barnola, J., Kawamura, K., Caillon, N., Delmotte, M., Van Ommen, T., Dreyfus, G., Jouzel, J., Masson-Delmotte, V., Minster, B., Freitag, J., Leuenberger, M., Schwander, J., Huber, C., Etheridge, D., and Morgan, V: Firn-air $^15$N in modern polar sites and glacial-interglacial ice: a model-data mismatch during glacial periods in Antarctica?, Quat. Sci. Rev., 25(1–2), 49–62, 2005. Lhomme, N: Modelling water isotopes in polar ice sheets, PhD thesis, Université Joseph Fourier, Grenoble, 2004. Lisiecki, L. E. and Raymo, M. E: A Plio-Pleistocene Stack of 57 Globally Distributed Benthic $\delta ^18$O Records, Paleoceanography, 20(1), PA1003, doi:10.1029/2004PA001071, 2005. Lliboutry, L: A critical review of analytical approximate solutions for steady state velocities and temperature in cold ice sheets, Z. Gletscherkd. Glacialgeol., 15(2), 135–148, 1979. Lliboutry, L. and Duval, P: Various isotropic and anisotropic ices found in glacier and polar ice caps and their corresponding rheologies, Ann. Geophys., 3(2), 207–224, 1985. Lorius, C. and Merlivat, L: Distribution of mean surface stable isotope values in east Antarctica. Observed changes with depth in a coastal area, in: Isotopes and impurities in snow and ice. proceedings of the grenoble symposium aug./sep. 1975, volume 118 of IAHS Publication, IAHS, Vienna, 1977. Narcisi, B., Petit, J.-R., and Tiepolo, M: A volcanic marker (92 kyr) for dating deep East Antarctic cores, Quat. Sci. Rev., 25, 2682–2687, 2006. Narita, H., Azuma, N., Hondoh, T., Hori, A., Hiramatsu, T., Fujii-Miyamoto, M., Satow, K., Shoji, H., and Watanabe, O: Estimation of annual layer thickness from stratigraphical analysis of dome fuji deep ice core (scientific paper), Memoirs of National Institute of Polar Research, Special issue, 57, 38–45, 2003. Parrenin, F., Hindmarsh, R., and Rémy, F: Analytical solutions for the effect of topography, accumulation rate and lateral flow divergence on isochrone layer geometry, J. Glaciol., 52(177), 191–202, 2006. Parrenin, F., Jouzel, J., Waelbroeck, C., Ritz, C., and Barnola, J.-M: Dating the Vostok ice core by an inverse method, J. Geophys. Res., 106(D23), 31 837–31 851, 2001. Parrenin, F., Remy, F., Ritz, C., Siegert, M., and Jouzel, J: New modelling of the Vostok ice flow line and implication for the glaciological chronology of the Vostok ice core, J. Geophys. Res., 109, D20102, doi:10.1029/2004JD004561, 2004. Raisbeck, G. M., Yiou, F., Bard, E., Dollfus, D., Jouzel, J. and Petit, J. R: Absolute dating of the last 7000 years of the Vostok ice core using $^10$Be, Mineral. Mag., 62A, 1228, 1998. Rasmussen, S. O., Andersen, K. K., Svensson, A. M., Steffensen, J. P., Vinther, B. M., Clausen, H. B., Siggaard-Andersen, M.-L., Johnsen, S. J., Larsen, L. B., Dahl-Jensen, D., Bigler, M., Rothlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M. E. and Ruth, U: A new Greenland ice core chronology for the last glacial termination, J. Geophys. Res., 111, D06102, doi:10.1029/2005JD006079, 2006. Raymond, C. F: Deformation in the vicinity of ice divides, J. Glaciol., 29(103), 357–373, 1983. Ritz, C., Rommelaere, V., and Dumas, C: Modeling the evolution of Antarctic ice sheet over the last 420 000 years: implications for altitude changes in the Vostok region, J. Geophys. Res., 106(D23), 31 943–31 964, 2001. Ritz, C: Interpretation of the temperature profile measured at Vostok, East Antarctica, Ann. Glaciol., 12, 138–144, 1989. Rémy, F., Shaeffer, P., and Legrésy, B: Ice flow pysical processes derived from the ERS-1 high-resolution map of the Antarctica and Greenland ice sheets, Geophys. J. Int., 139, 645–656, 1999. Rémy, F. and Tabacco, I: Bedrock features and ice flow near the EPICA ice core site (Dome C, Antarctica), Geophys. Res. Lett., 27(3), 405–408, 2000. Saito, F. and Abe-Ouchi, A: Thermal structure of Dome Fuji and east Dronning Maud Land, Antarctica, simulated by a three-dimensional ice-sheet model, Ann. Glaciol., 39, 433–438, 2002. Salamatin, A. N., Tsiganova, E. A., Lipenkov, V. Y., and Petit, J. R: Vostok (Antarctica) ice-core time scale from datings of different origins, Ann. Glaciol., 39, 283–292, 2004. Salamatin, A. N. and Ritz, C: A simplified multi-scale model for predicting climatic variations of the ice-sheet suface elevation in central Antarctica, Ann. Glaciol., 23, 28–35, 1996. Schwander, J., Jouzel, J., Hammer, C. U., Petit, J.-R., Udisti, R., and Wolff, E: A tentative chronology for the EPICA Dome Concordia ice core, Geophys. Res. Lett., 28(22), 4243–4246, 2001. Stenni, B., Jouzel, J., Masson-Delmotte, V., Rothlisberger, R., Castellano, E., Cattani, O., Falourd, S., Johnsen, S., Longinelli, A., Sachs, J., Selmo, E., Souchez, R., Steffensen, J., and Udisti, R: A late-glacial high-resolution site and source temperature record derived from the EPICA Dome C isotope records (East Antarctica), Earth. Planet. Sci. Lett., 217, 183–195, 2003. Svensson, A., Krogh Andersen, K., Bigler, M., Clausen, H. B., Dahl-Jensen, D., Davies, S. M., Johnsen, S. J., Muscheler, R., Rasmussen, S. O., Röthlisberger, R., Steffensen, J. P., and Vinther, B. M: The Greeland ice core chronology 2005, 15-42 kyr. Part 2: Comparison to other records, Quat. Sci. Rev., in Press, 2007. Tabacco, I. E., Passerini, A., Corbelli, F., and Gorman, M: Determination of the surface and bed topography at Dome C, East Antarctica, J. Glaciol., 44, 185–191, 1998. Thorsteinsson, T., Kipfstuhl, J., and Miller, H: Textures and fabrics in the GRIP ice core, J. Geophys. Res., 102(C12), 26 583–26 600, 1997. Van Ommen, T., Morgan, V., and Curran, M: Deglacial and Holocene changes in accumulation at Law Dome, East Antarctica, Ann. Glaciol., 39, 359–365, 2004. Vimeux, F., Cuffey, K., Jouzel, J., Stievenard, M., and Petit, J. R: New Insights into Southern Hemisphere temperature changes from Vostok ice cores using deuterium excess correction, Earth Planet. Sci. Lett., 203, 829–843, 2002. Vittuari, L., Vincent, C., Frezzotti, M., Mancini, F., Gandolfi, S., Bitelli, G., and Capra, A: Space geodesy as a tool for measuring ice surface velocity in the Dome C region and along the ITASE traverse, Ann. Glaciol., 39, 402–408, 2004. Watanabe, O., Jouzel, J., Johnsen, S., Parrenin, F., Shoji, H., and Yoshida, N: Homogeneous climate variability across East Antarctica over the past three glacial cycles, Nature, 422, 509–512, 2003. Watanabe, O., Kamiyama, K., Motoyama, H., Fujii, Y., Igarashi, M., Furukawa, T., Goto-Azuma, K., Saito, T., Kanamori, S., Kanamori, N., Yoshida, N., and Uemura, R: General tendencies of stable isotopes and major chemical constituents of the dome fuji deep ice core, Memoirs of National Institute of Polar Research, Special issue, 57, 1–24, 2003. Watanabe, O., Kamiyama, K., Motoyama, H., Fujii, Y., Shoji, H., and Satow, K: The paleoclimate record in the ice core at Dome Fuji station, East Antarctica, Ann. Glaciol., 29, 176–178, 1999. Watanabe, O., Shoji, H., Satow, K., Motoyama, H., Fujii, Y., Narita, H., and Aoki, S: Dating of the dome fuji, antarctica deep ice core, Memoirs of National Institute of Polar Research. Special issue, 57, 25–37, 2003.