Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 6 4 2010 10.5194/cpd-6-1551-2010 http://www.clim-past-discuss.net/6/1551/2010/ http://www.clim-past-discuss.net/6/1551/2010/cpd-6-1551-2010.html http://www.clim-past-discuss.net/6/1551/2010/cpd-6-1551-2010.pdf 1551 1588 2010-08-30 Greenland Ice Sheet model parameters constrained using simulations of the Eemian Interglacial A. Robinson robinson@pik-potsdam.de R. Calov A. Ganopolski Potsdam Institute for Climate Impact Research, Potsdam, Germany University of Potsdam, Potsdam, Germany Using a new approach to force an ice sheet model, we performed an ensemble of simulations of the Greenland Ice Sheet evolution during the last two glacial cycles, with emphasis on the Eemian Interglacial. This ensemble was generated by perturbing four key parameters in the coupled regional climate – ice sheet model and by introducing additional uncertainty in the prescribed "background" climate change. Sensitivity of the surface melt model to climate change was determined to be the dominant driver of ice sheet instability, as reflected by simulated ice sheet loss during the Eemian Interglacial period. To eliminate unrealistic parameter combinations, constraints from present-day and paleo information were applied. The constraints include (i) the diagnosed present-day surface mass balance partition between surface melting and calving, (ii) the modeled present-day elevation at GRIP; and (iii) the modeled elevation reduction at GRIP during the Eemian. Using these three constraints, a total of 270 simulations with 90 different model realizations were filtered down to 47 simulations and 20 model realizations considered valid. The paleo constraint eliminated more sensitive melt parameter values, in agreement with the surface mass balance partition assumption. The constrained simulations result in a range of Eemian ice loss of 0.4–4.1 m sea level (m.s.l.) equivalent, with a more likely value of about 4.1 m.s.l. if the GRIP δ<sup>18</sup>O isotope record can be considered an accurate proxy for the precipitation-weighted annual mean temperatures. Alley, R. B., Andrews, J. T., Brigham-Grette, J., Clarke, G. K. C., Cuffey, K. M., Fitzpatrick, J. J., Funder, S., Marshall, S. J., Miller, G. H., Mitrovica, J. X., Muhs, D. R., Otto-Bliesner, B. L., Polyak, L., and White, J. W. C.: History of the Greenland Ice Sheet: paleoclimatic insights, Quat. Sci. Rev., 29, 1728–1756, doi:10.1016/j.quascirev.2010.02.007, 2010. Alley, R. B., Gow, A. J., Johnsen, S. J., Kipfstuhl, J., Meese, D. A., and Thorsteinsson, T.: Comparison of deep ice cores, Nat. 373, 393–394, 1995. Bamber, J. L., Ekholm, S., and Krabill, W. B.: A new, high-resolution digital elevation model of Greenland fully validated with airborne laser altimeter data, J. Geophys. Res., 106 (B4), 6733–6745, 2001. Berger, A.: Long-term variations of daily insolation and Quaternary climatic change, J. Atmos. Sci., 35, 2362–2367, 1978. Bonelli, S., Charbit, S., Kageyama, M., Woillez, M.-N., Ramstein, G., Dumas, C., and Quiquet, A.: Investigating the evolution of major Northern Hemisphere ice sheets during the last glacial-interglacial cycle, Clim. Past, 5, 329–345, doi:10.5194/cp-5-329-2009, 2009. Box, J. E., Bromwich, D. H., Veenhuis, B. A., Bai, L. S., Stroeve, J. C., Rogers, J. C., Steffen, K., Haran, T., and Wang, S. H.: Greenland ice sheet surface mass balance variability (1988–2004) from calibrated polar MM5 output, J. Climate, 19, 2783–2800, 2006. Braithwaite, R. J. and Olesen, O. B.: Calculation of glacier ablation from air temperature, West Greenland, in: Glacier fluctuations and climatic change, edited by: Oerlemans, J., Kluwer Academic Publishers, Dordrecht, 219–233, 1989. Calov, R., Ganopolski, A., Claussen, M., Petoukhov, V., and Greve, R.: Transient simulation of the last glacial inception with an atmosphere-ocean-vegetation-ice sheet Part I: Glacial inception as a bifurcation of the climate system, Clim. Dynam., 24, 545–561, 2005. Calov, R., Ganopolski, A., Petoukhov, V., Claussen, M., and Greve, R.: Large-scale instabilities of the Laurentide Ice Sheet simulated in a fully coupled climate-system model, Geophys. Res. Lett., 29, 2216, doi:10.1029/2002GL016078, 2002. CAPE Last Interglacial Project Members: Last Interglacial arctic warmth confirms polar amplification of climate change, Quat. Sci. Rev., 25, 1383–1400, 2006. Claussen, M., Mysak, L. A., Weaver, A. J., Crucifix, M., Fichefet, T., Loutre, M.-F., Weber, S. L., Alcamo, J., Alexeev, V. A., Berger A., Calov, R., Ganopolski, A., Goosse, H., Lohman, G., Lunkeit, F., Mokhov, I.I., Petoukhov, V., Stone, P., and Wang, Zh.: Earth system models of intermediate complexity: Closing the gap in the spectrum of climate system models, Clim. Dynam., 18, 579–586, 2002. Cuffey, K. M. and Marshall, S. J.: Substantial contribution to sea-level rise during the last interglacial from the Greenland ice sheet, Nature, 404, 591–594, 2000. Dansgaard, W., Clausen, H. B., Gundestrup, N., Johnsen, S., and Rygner, C.: Dating and Climatic Interpretation of Two Deep Greenland Ice Cores, in: Greenland Ice Core: Geophysics, Geochemistry, and the Environment, edited by: Langway, C. C. J., Oeschger, H., and Dansgaard, W., AGU, Washington, DC, 71–76, 1985. Ettema, J., van den Broeke, M. R., van Meijgaard, E., van de Berg,~W. J., Bamber,~J. L., Box,~J. E., and Bales,~R. C.: Higher surface mass balance of the Greenland ice sheet revealed by high-resolution climate modeling, Geophys. Res. Lett.,36, L12501, doi:10.1029/2009GL038110, 2009. Fettweis, X.: Reconstruction of the 1979–2006 Greenland ice sheet surface mass balance using the regional climate model MAR, The Cryosphere, 1, 21–40, doi:10.5194/tc-1-21-2007, 2007. Ganopolski, A., Calov, R., and Claussen, M.: Simulation of the last glacial cycle with a coupled climate ice-sheet model of intermediate complexity, Clim. Past, 6, 229–244, doi:10.5194/cp-6-229-2010, 2010. Ganopolski, A., Petoukhov, V., Rahmstorf, S., Brovkin, V., Claussen, M., Eliseev, A., and Kubatzki C.: CLIMBER-2: a climate system model of intermediate complexity. Part II: Model sensitivity, Clim. Dynam., 17, 735–751, 2001. Greenland Ice-core Project (GRIP) Members: Climate instability during the last interglacial period recorded in the GRIP ice core, Nature, 364, 203–208, 1993. Gregory, J. M. and Huybrechts, P: Ice-sheet contributions to future sea-level change, Philos. Tr. R. Soc. Lond. A, 364, 1709–1731, 2006. Gregory, J. M., Huybrechts, P., and Raper, S. C. B.: Threatened loss of the Greenland ice-sheet, Nature, 428, 616, doi:10.1038/428616a, 2004. Greve, R.: Relation of measured basal temperatures and the spatial distribution of the geothermal heat flux for the Greenland ice sheet, Ann. Glaciol., 42, 424–432, 2005. Greve, R.: On the response of the Greenland ice sheet to greenhouse climate change, Climatic Change, 46, 289–303, 2000. Greve, R.: Application of a polythermal three-dimensional ice sheet model to the Greenland Ice Sheet: Response to steady-state and transient climate scenarios, J. Climate, 10 (5), 901–918, 1997a. Greve, R.: A continuum-mechanical formulation for shallow polythermal ice sheets, Philos. Tr. R. Soc. Lond., 355 (1726), 921–974, 1997b. Huybrechts, P.: Sea-level changes at the LGM from ice-dynamic reconstructions of the Greenland and Antarctic ice sheets during the glacial cycles, Quat. Sci. Rev., 21, 203–231, 2002. Huybrechts, P., Letréguilly, A., and Reeh, N.: The Greenland ice sheet and Greenhouse warming, Palaeogeography, palaeoclimatology, palaeoecology, 89, 399–412, 1991. Imbrie, J., Hays, J. D., Martinson, D. G., McIntyre, A., Mix, A. C., Morley, J. J., Pisias, N. G., Prell, W. L., and Shackleton, N. J.: The orbital theory of Pleistocene climate: Support from a revised chronology of the marine $\delta $18O record, in: Milankovitch and Climate, Part I, NATO ASI Series C: Mathematical and Physical Sciences,edited by: Berger, A., Hays, J., Kukla, G., and Saltzman, B., Reidel, Dordrecht, 269–305, 1984. Jansen, E., Overpeck, J., Briffa, K. R., Duplessy, J. C., Joos, F., Masson-Delmotte, V., Olago, D., Otto-Bliesner, B., Peltier, W. R., Rahmstorf, S., Ramesh, R., Raynaud, D., Rind, D., Solomina, O., Villalba, R., and Zhang, D.: Palaeoclimate, in: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M. and Miller, H. L., Cambridge University Press, Cambridge, UK and New York, NY, USA, 434–498, 2007. Johnsen, S., Dahl-Jensen, D., Gundestrup, N., Steffensen, J. P., Clausen, H. B., Miller, H., Masson-Delmotte, V., Sveinboernsdottir, A. E., and White, J.: Oxygen isotope and paleotemperature records from six Greenland ice-core stations: Camp Century, Dye-3, GRIP, GISP2, Renland and NorthGRIP, J. Quat. Sci., 16, 299–307, doi:10.1002/jqs.622, 2001. Jouzel, J., Alley, R. B., Cuffey, K. M., Dansgaard, W., Grootes, P., Hoffmann, G., Johnsen, S. J., Koster, R. D., Peel, D. Shuman, C. A., Stievenard, M., Stuiver, M., and White, J.: Validity of the temperature reconstruction from water isotopes in ice cores,~J. Geophys. Res.,~102, 26471–26487, doi:10.1029/97JC01283, 1997. Kopp, R. E., Simons, F. J., Mitrovica, J. X., Maloof, A. C., and Oppenheimer, M.: Probabilistic assessment of sea level during the last interglacial stage, Nature, 462, 863–867, doi:10.1038/nature08686, 2009. Lhomme, N., Clarke, G. K. C., and Marshall, S. J.: Tracer transport in the Greenland Ice Sheet: constraints on ice cores and glacial history, Quat. Sci. Rev., 24, 173–194, 2005. Masson-Delmotte, V., Stenni, B., Pol, K., Braconnot, P., Cattani, O., Falourd, S., Kageyama, M., Jouzel, J., Landais, A., Minster, B., Barnola, J. M., Chappellaz, J., Krinner, G., Johnsen, S., Röthlisberger, R., Hansen, J., Mikolajewicz, U., and Otto-Bliesner, B.: EPICA Dome C record of glacial and interglacial intensities, Quat. Sci. Rev., 29, 113–128, 2010. Otto-Bliesner, B. L., Marshall, S. J., Overpeck, J. T., Miller, G. H., Hu, A., et al.: Simulating Arctic climate warmth and icefield retreat in the last interglaciation, Science, 311, 1751–1753, 2006. North Greenland Ice Core Project Members: High-resolution record of Nothern Hemisphere climate extending into the last interglacial period, Nat., 431, 147–151, 2004. Overpeck, J. T., Otto-Bliesner, B. L., Miller, G. H., Muhs, D. R., Alley, R. B., and Kiehl, J. T.: Paleoclimatic Evidence for Future Ice-Sheet Instability and Rapid Sea-Level Rise, Sci., 311, 1747–1750, 2006. Petoukhov V., Ganopolski, A., Brovkin, V., Claussen, M., Eliseev, A., Kubatzki, C., and Rahmstorf, S.: CLIMBER-2: a climate system model of intermediate complexity. Part I: model description and performance for present climate, Clim. Dynam., 16 (1), 1–17, 2000. Raynaud, D., Chappellaz, J., Ritz, C., and Martinerie, P.: Air content along the Greenland Ice Core Project core: A record of surface climatic parameters and elevation in central Greenland, J. Geophys. Res., 102, 607–626, 1997. Reeh, N.: Parameterization of melt rate and surface temperature on the Greenland ice sheet, Polarforschung, 59, 113–128, 1991. Ritz, C., Fabré, A. and Letréguilly, A.: Sensitivity of a Greenland ice sheet model to ice flow and ablation parameters: consequences for the evolution through the last climatic cycle, Clim. Dynam., 13, 11–24, 1997. Robinson, A., Calov, R., and Ganopolski, A.: An efficient regional energy-moisture balance model for simulation of the Greenland Ice Sheet response to climate change, The Cryosphere, 4, 129–144, doi:10.5194/tc-4-129-2010, 2010. Shapiro, N. M. and Ritzwoller, M. H.: Inferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica, Earth Planet. Sc. Let., 223, 213–224, 2004. Tarasov, L. and Peltier, W. R.: Greenland glacial history and local geodynamic consequences, Geophys. J. Int., 150, 198–229, 2002. Tarasov, L. and Peltier, W. R.: Greenland glacial history, borehole constraints, and Eemian extent, J. Geophys. Res., 108, 2143–2163, doi:10.1029/2001JB001731, 2003. Uppala, S. M., Kållberg, P. W., Simmons, A., et al.: The ERA-40 re-analysis, Q. J. Roy. Meteorol. Soc., 131 (612), 2961–3012, 2005. van den Berg, J., van de Wal, R. S., and Oerlemans, J.: A mass balance model for the Eurasian Ice Sheet for the last 120 000 years, Global Planet. Change, 61, 194–208, doi:10.1016/j.gloplacha.2007.08.015, 2008. Vinther, B., Buchardt, S. L., Clausen, H. B., Dahl-Jensen, D., Johnsen, S. J., Fisher, D. A., Koerner, R. M., Raynaud, D., Lipenkov, V., Andersen, K. K., Blunier, T., Rasmussen, S. O., Steffensen, J. P., and Svensson, A. M.: Holocene thinning of the Greenland ice sheet, Nat., 461, 385–388, doi:10.1038/nature08355, 2009. Willerslev, E., Cappellini, E., Boomsma, W., Nielsen, R., Hebsgaard, M. B., Brand, T. B., Hofreiter, M., Bunce, M., Poinar, H. N., Dahl-Jensen, D., Johnsen, S., Steffensen, J. P., Bennike, O., Schwenninger, J., Nathan, R., Armitage, S., de Hoog, C., Alfimov, V., Christl, M., Beer, J., Muscheler, R., Barker, J., Sharp, M., Penkman, K. E. H., Haile, J., Taberlet, P., Gilbert, M. T. P., Casoli, A., Campani, E., and Collins, M. J.: Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland, Sci., 317, 111–114, doi:10.1126/science.1141758, 2007.