Climate of the Past www.clim-past.net 1814-9324 1814-9332 3 1 2007 10.5194/cp-3-1-2007 http://www.clim-past.net/3/1/2007/ http://www.clim-past.net/3/1/2007/cp-3-1-2007.html http://www.clim-past.net/3/1/2007/cp-3-1-2007.pdf 1 14 2007-01-15 Exposure dating of Late Glacial and pre-LGM moraines in the Cordon de Doña Rosa, Northern/Central Chile (~31° S) R. Zech roland.zech@giub.unibe.ch Ch. Kull P. W. Kubik H. Veit Geographical Institute, University of Bern, Hallerstr. 12, 3012 Bern, Switzerland PAGES IPO, Sulgeneckstrasse 38, 3007 Bern, Switzerland Paul Scherrer Institute c/o Institute of Particle Physics, ETH Zurich, 8093 Zurich, Switzerland Despite the important role of the Central Andes (15–30° S) for climate reconstruction, knowledge about the Quaternary glaciation is very limited due to the scarcity of organic material for radiocarbon dating. We applied ¹⁰Be surface exposure dating (SED) on 22 boulders from moraines in the Cordon de Doña Rosa, Northern/Central Chile (~31° S). The results show that several glacial advances in the southern Central Andes occurred during the Late Glacial between ~14.7±1.5 and 11.6±1.2 ka. A much more extensive glaciation is dated to ~32±3 ka, predating the temperature minimum of the global LGM (Last Glacial Maximum: ~20 ka). Reviewing these results in the paleoclimatic context, we conclude that the Late Glacial advances were most likely caused by an intensification of the tropical circulation and a corresponding increase in summer precipitation. High-latitude temperatures minima, e.g. the Younger Dryas (YD) and the Antarctic Cold Reversal (ACR) may have triggered individual advances, but current systematic exposure age uncertainties limit precise correlations. The absence of LGM moraines indicates that moisture advection was too limited to allow significant glacial advances at ~20 ka. The tropical circulation was less intensive despite the maximum in austral summer insolation. Winter precipitation was apparently also insufficient, although pollen and marine studies indicate a northward shift of the westerlies at that time. The dominant pre-LGM glacial advances in Northern/Central Chile at ~32 ka required lower temperatures and increased precipitation than today. We conclude that the westerlies were more intense and/or shifted equatorward, possibly due to increased snow and ice cover at higher southern latitudes coinciding with a minimum of insolation. Ammann, C., Jenny, B., Kammer, K., and Messerli, B.: Late Quaternary Glacier response to humidity changes in the arid Andes of Chile (18–29° S), Palaeogeography, Palaeoclimatology, Palaeoecology, 172, 313–326, 2001. Anderson, J. B., Shipp, S. S., Lowe, A. L., Wellner, J. S., and Mosola, A. B.: The Antarctic Ice Sheet during the Last Glacial Maximum and its subsequent retreat history: a review, Quat. Sci. Rev., 21(1–3), 49–70, 2002. Baker, P. A., Rigsby, C. A., Seltzer, G. O., Fritz, S. C., Lowenstein, T. K., Bacher, N. P., and Veliz, C.: The history of South American tropical precipitation for the past 25,000 years, Science, 291, 640–643, 2001a. Baker, P. A., Rigsby, C. A., Seltzer, G. O., Fritz, S. C., Lowenstein, T. K., Bacher, N. P., and Veliz, C.: Tropical climate changes at millennial and orbital timescales on the Bolivian Altiplano, Nature, 409, 698–701, 2001b. Berger, A. and Loutre, M. F.: Insolation values for the climate of the last 10 million of years, Quat. Sci. Rev., 10(4), 297–317, 1991. Briner, J. P., Kaufman, D. S., Manley, W. F., Finkel, R. C., and Caffee, M. W.: Cosmogenic exposure dating of late Pleistocene moraine stabilization in Alaska, GSA Bulletin, 117(7), 1108–1120, 2005. Clapperton, C. M., Clayton, J. D., Benn, D. I., Marden, C. J., and Argollo, J.: Late Quaternary glacier advances and palaeolake highstands in the Bolivian Altiplano, Quaternary International, 38–39, 49–59, 1997. Clayton, J. D. and Clapperton, C. M.: Broad Synchrony of a Late-Glacial Glacier Advance and the Highstand of Palaeolake Tauca in the Bolivian Altiplano, Journal of Quaternary Science, 12, 169–182, 1997. Clemens, S., Prell, W., Murray, D., Shimmield, G. and Weedon, G.: Forcing mechanisms of the Indian Ocean monsoon, Nature, 353, 720–725, 1991. Clement, A. C., Hall, A., and Broccoli, A. J.: The importance of precessional signals in the tropical climate, Climate Dynamics, 22(4), 327–341, 2004. Cruz, F. W., Burns, S. J., Karmann, I., Sharp, W. D., Vuille, M., Cardoso, A. O., Ferrari, J. A., Silva Dias, P. L., and Viana, O.: Insolation-driven changes in atmospheric circulation over the past 116,000 years in subtropical Brazil, Nature, 434, 63–66, 2005. Cruz, F. W., Burns, S. J., Karmann, I., Sharp, W. D., and Vuille, M.: Reconstruction of regional atmospheric circulation features during the late Pleistocene in subtropical Brazil from oxygen isotope composition of speleothems, Earth Planet. Sci. Lett., 248(1–2), 495–507, 2006. Denton, G. H., Lowell, T. V., Heusser, C. J., Schlüchter, C., Andersen, B. G., Heusser, L. E., Moreno, P. I., and Marchant, D. R.: Geomorphology, stratigraphy, and radiocarbon chronology of Llanquihue drift in the area of the southern Lake District, Seno Reloncavi, and Isla Grande de Chiloe, Chile, Geografiska Annaler, 81(A), 167–229, 1999. Desilets, D. and Zreda, M.: Spatial and temporal distribution of secondary cosmic-ray nucleon intensities and applications to in situ cosmogenic dating, Earth Planet. Sci. Lett., 206, 21–42, 2003. Dunai, T. J.: Influence of secular variation of the geomagnetic field on production rates of in situ produced cosmogenic nuclides, Earth Planet. Sci. Lett., 193, 197–212, 2001. Dunne, A., Elmore, D., and Muzikar, P.: Scaling factors for the rates of production of cosmogenic nuclides for geometric shielding and attenuation at depth on sloped surfaces, Geomorphology, 27, 3–11, 1999. Espizua, L. E.: Pleistocene glaciations in the Mendoza Andes, Argentina, in: Quaternary Glaciations – Extent and Chronology. Part III: South America, Asia, Africa, Australasia, Antarctica, edited by: Ehlers, J. and Gibbard, P. L., Cambridge, 2004. Garleff, K. and Stingl, H. (Eds.): Südamerika: Geomorphologie und Paläoökologie im jüngeren Quartär, Bamberger Geographische Schriften, 11, 1991. Garleff, K. and Stingl, H. (Eds.): Landschaftsentwicklung, Paläoökologie und Klimageschichte der Ariden Diagonale Südamerikas im Jungquartär, Bamberger Geographische Schriften, 15, 1998. Garreaud, R., Vuille, M., and Clement, A. C.: The climate of the Altiplano: observed current conditions and mechanisms of past changes, Palaeogeography, Palaeoclimatology, Palaeoecology, 194(1–3), 5–22, 2003. Gasse, F.: Hydrological changes in the African tropics since the Last Glacial Maximum, Quat. Sci. Rev., 19, 189–211, 2000. Geyh, M. A., Grosjean, M., Nunez, L., and Schotterer, U.: Radiocarbon Reservoir Effect and the Timing of the Late-Glacial/Early Holocene Humid Phase in the Atacama Desert (Northern Chile), Quaternary Research, 52, 143–153, 1999. Gosse, J. C. and Phillips, F. M.: Terrestrial in situ cosmogenic nuclides: theory and application, Quat. Sci. Rev., 20, 1475–1560, 2001. Grosjean, M., Cartajena, I., Geyh, M. A., and Nunez, L.: From proxy data to paleoclimate interpretation: the mid-Holocene paradox of the Atacama Desert, northern Chile, Palaeogeography, Palaeoclimatology, Palaeoecology, 194(1–3), 247–258, 2003. Grosjean, M., Van Leeuwen, J. F. N., Van Der Knaap, W. O., Geyh, M. A., Ammann, B., Tanner, W., Messerli, B., and Veit, H.: A 22,000 14C yr BP sediment and pollen record of climate change from Laguna Miscanti 231S, northern Chile, Global and Planetary Change, 28, 35–51, 2001. Guyodo, Y. and Valet, J.-P.: Relative variations in geomagnetic intensity from sedimentary records: the past 200.000 years, Earth Planet. Sci. Lett., 143, 23–26, 1996. Hallet, B. and Putkonen, J.: Surface dating of dynamic landforms: young boulders on aging moraines, Science, 265, 937–940, 1994. Harrison, S. P.: The Pleistocene glaciations of Chile, in: Quaternary Glaciations – Extent and Chronology. Part III: South America, Asia, Africa, Australasia, Antarctica, edited by: Ehlers, J. and Gibbard, P. L., Cambridge, 2004. Heine, K.: Late Quaternary glaciations of Bolivia, in: : Quaternary Glaciations – Extent and Chronology. Part III: South America, Asia, Africa, Australasia, Antarctica, edited by: Ehlers, J. and Gibbard, P. L., Cambridge, 2004. Heisinger, B., Lal, D., Jull, A. J. T., Kubik, P., Ivy-Ochs, S., Knie, K., and Nolte, E.: Production of selected cosmogenic radionuclides by muons 2. Capture of negative muons, Earth Planet. Sci. Lett., 200, 357–369, 2002a. Heisinger, B., Lal, D., Jull, A. J. T., Kubik, P., Ivy-Ochs, S., Neumaier, S., Knie, K., Lazarev, V., and Nolte, E.: Production of selected cosmogenic radionuclides by muons 1. Fast muons, Earth Planet. Sci. Lett., 200, 345–355, 2002b. Heusser, C. J.: Southern westerlies during the last glacial maximum, Quaternary Research, 31, 423–425, 1989. Heusser, C. J.: Ice Age Southern Andes – A Chronicle of Paleoecological Events, Elsevier, pp 240, 2003. Ivy-Ochs, S.: The dating of rock surface using in situ produced 10Be, 26Al and 36Cl, with examples from Antarctica and the Swiss Alps, Dissertation ETH No. 11763, Zürich, 197 pp., 1996. Jenny, B. and Kammer, K.: Climate Change in den trockenen Anden: Jungquartäre Vergletscherung, Geographica Bernensia, G46, 1–80, 1996. Kaser, G.: Glacier-climate interaction at low latitudes, Journal of Glaciology, 47(157), 195–204, 2001. Kubik, P. and Ivy-Ochs, S.: A re-evaluation of the 0–10 ka 10Be production rate for exposure dating obtained from the Köfels (Austria) landslide, Nuclear Instruments and Methods in Physics Research B, 223–224, 618–622, 2004. Kubik, P. W., Ivy-Ochs, S., Masarik, J., Frank, M., and Schlüchter, C.: 10Be and 26Al production rates deduced from an instantaneous event within the dendro-calibration curve, the landslide of Köfels, Ötz Valley, Austria, Earth Planet. Sci. Lett., 161, 231–241, 1998. Kull, C.: Modellierung paläoklimatischer Verhältnisse basierend auf der jungpleistozänen Vergletscherung in Nordchile – Ein Fallbeispiel aus den Nordchilenische Anden, Z. Gletscherk. Glazialgeol., 35, 35–64, 1999. Kull, C. and Grosjean, M.: Late Pleistocene climate conditions in the North Chilean Andes drawn from a Climate-Glacier Model, Journal of Glaciology, 46, 622–632, 2000. Kull, C., Grosjean, M., and Veit, H.: Modeling Modern and Late Pleistocene Glacio-Climatological Conditions in the North Chilean Andes (29–30°), Climatic Change, 52, 359–381, 2002. Kull, C., Hanni, F., Grosjean, M., and Veit, H.: Evidence of an LGM cooling in NW-Argentina (22° S) derived from a glacier climate model, Quaternary International, 108(1), 3–11, 2003. Lowell, T. V., Heusser, C. J., Andersen, B. G., Moreno, P. I., Hauser, A., Heusser, L. E., Schlüchter, C., Marchant, D. R., and Denton, G. H.: Interhemispheric correlations of Late Pleistocene glacial events, Science, 269, 1541–1549, 1995. Maldonado, A., Betancourt, J. L., Latorre, C., and Villagran, C.: Pollen analyses from a 50~000-yr rodent midden series in the southern Atacama Desert (25°30$'$ S), Journal of Quaternary Science, 20(5), 493–507, 2005. Mark, B. G., Seltzer, G. O., and Rodbell, D. T.: Late Quaternary glaciations of Ecuador, Peru and Bolivia, in: Quaternary Glaciations – Extent and Chronology. Part III: South America, Asia, Africa, Australasia, Antarctica, edited by: Ehlers, J. and Gibbard, P. L., Cambridge, 2004. Markgraf, V.: Reply to C. J. Heusser's "Southern Westerlies during the Last Glacial Maximum", Quaternary Research, 28, 426–432, 1989. Markgraf, V., Baumgartner, T. R., Bradbury, J. P., Diaz, H. F., B. Dunbar, R., Luckman, B. H., Seltzer, G. O., Swetnam, T. W., and Villalba, R.: Paleoclimate reconstruction along the Pole-Equator-Pole transect of the Americas (PEP 1), Quat. Sci. Rev., 19(1–5), 125–140, 2000. Masarik, J. and Reedy, R. C.: Terrestrial cosmogenic-nuclide production systematics calculated from numerical simulations, Earth Planet. Sci. Lett., 136, 381–395, 1995. Mcelhinny, M. W. and Senanayake, W. E.: Variations in the geomagnetic dipole 1: The past 50.000 years, Journal of Geomagnetism and Geoelectricity, 34, 39–51, 1982. Messerli, B.: Problems of vertical and horizontal arrangement in the high mountains of the extreme arid zone (Central Sahara), Arctic and Alpine Research, 5(A), 139–47, 1973. Mosola, A. B. and Anderson, J. B.: Expansion and rapid retreat of the West Antarctic Ice Sheet in eastern Ross Sea: possible consequence of over-extended ice streams?, Quat. Sci. Rev., 25(17–18), 2177-2196, 2006. Ngrip Members: High-resolution record of Northern Hemisphere climate extending into the last interglacial period, Nature, 431, 147–151, 2004. Ohno, M. and Hamano, Y.: Geomagnetic poles over the past 10.000 years, Geophys. Res. Lett., 19, 1715–1718, 1992. Owen, L. A., Finkel, R. C., Barnard, P. L., Haizhou, M., Asahi, K., Caffee, M. W., and Derbyshire, E.: Climatic and topographic controls on the style and timing of Late Quaternary glaciation throughout Tibet and the Himalaya defined by 10Be cosmogenic radionuclide surface exposure dating, Quat. Sci. Rev., 24(12–13), 1391–1411, 2005. Petit, J. R., Jouzel, J., Raynaud, D., Barkov, N. I., Barnola, J.-M., Basile, I., Bender, M., Chappellaz, J., Davis, M., Delaygue, G., Delmotte, M., Kotlyakov, V. M., Legrand, M., Lipenkov, V. Y., Lorius, C., Pepin, L., Ritz, C., Saltzman, E., and Stievenard, M.: Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica, Nature, 399(6735), 429–436, 1999. Pigati, J. S. and Lifton, N. A.: Geomagnetic effects on time-integrated cosmogenic nuclide production with emphasis on in situ 14C and 10Be, Earth Planet. Sci. Lett., 226, 193–205, 2004. Placzek, C., Quade, J., and Patchett, P. J.: Geochronology and stratigraphy of late Pleistocene lake cycles on the southern Bolivian Altiplano: Implications for causes of tropical climate change, GSA Bulletin, 118(5), 515–532, 2006. Putkonen, J. and Swanson, T.: Accuracy of cosmogenic ages for moraines, Quaternary Research, 59, 255–261, 2003. Shanahan, T. M. and Zreda, M.: Chronology of Quaternary glaciations in East Africa, Earth Planet. Sci. Lett., 177, 23–42, 2000. Shulmeister, J., Fink, D., and Augustinus, P. C.: A cosmogenic nuclide chronology of the last glacial transition in North-West Nelson, New Zealand–new insights in Southern Hemisphere climate forcing during the last deglaciation, Earth Planet. Sci. Lett., 233(3–4), 455–466, 2005. Singer, B.: 40Ar/39Ar evidence for early deglaciation of the central Chilenian Andes, Geophysical Research Letters, 27(11), 1663–1666, 2000. Smith, J. A., Seltzer, G. O., Farber, D. L., Rodbell, D. T., and Finkel, R. C.: Early Local Last Glacial Maximum in the Tropical Andes, Science, 308, 678–681, 2005. Stone, J. O.: Air pressure and cosmogenic isotope production, J. Geophys. Res., 105, 23 753–23 759, 2000. Stuut, J.-B. W. and Lamy, F.: Climate variability at the southern boundaries of the Namib (southwestern Africa) and Atacama (northern Chile) coastal deserts during the last 120,000 yr, Quaternary Research, 62(3), 301–309, 2004. Stuut, J.-B. W., Marchant, D. R., Kaiser, J., Lamy, F., Mohtadi, M., Romero, O. E., and Hebbeln, D.: The Late Quaternary paleoenvironment of Chile as seen from marine archives, Geographica Helvetica, 61, 135–151, 2006. Sylvestre, F., Servant, M., Servant-Vildary, S., Causse, C., Fournier, M. and Ybert, J.-P.: Lake-Level Chronology on the Southern Bolivian Altiplano (18–23 S) during Late-Glacial Time and the Early Holocene, Quaternary Research, 51, 54–66, 1999. Valdes, P. J.: South American palaeoclimate model simulations: how reliable are the models?, Journal of Quaternary Science, 15(4), 357–368, 2000. Valero-Garcés, B. L., Jenny, B., Rondanelli, M., Delgado-Huertas, A., Burns, S. J., Veit, H., and Moreno, A.: Palaeohydrology of Laguna de Tagua Tagua (34°30$'$ S) and moisture fluctuations in Central Chile for the last 46~000~yr, Journal of Quaternary Science, 20(7–8), 625–641, 2005. Veit, H.: Jungquartäre Landschafts- und Klimaentwicklung der zentralen Anden und ihres westlichen Vorlandes: Kenntnisse und Probleme, Geomethodica, 20, 163–194, 1995. Veit, H.: Quartäre Landschaft- und Klimageschichte Südamerikas, in: Naturraum Lateinamerika, edited by: Borsdorf, A. and Hödl, W., Wien, 2006. Vuille, M. and Ammann, C.: Regional Snowfall Patterns in the High, Arid Andes (South America), Clim. Change, 36, 413–423, 1997. Vuille, M. and Keimig, F.: Interannual Variability of Summertime Convective Cloudiness and Precipitation in the Central Andes Derived from ISCCP-B3 Data, J. Clim., 17(17), 3334–3348, 2004. Wang, X., Auler, A. S., Edwards, R. L., Cheng, H., Ito, E., and Solheid, M.: Interhemispheric anti-phasing of rainfall during the last glacial period, Quat. Sci. Rev., in press, 2007. Wang, Y. J., Cheng, H., Edwards, R. L., An, Z. S., Wu, J. Y., Shen, C.-C., and Dorale, J. A.: A High-Resolution Absolute-Dated Late Pleistocene Monsoon Record from Hulu Cave, China, Science, 294(5550), 2345–2348, 2001. Wyrwoll, K.-H., Dong, B., and Valdes, P.: On the Position of Southern Hemisphere Westerlies at the Last Glacial Maximum: An Outline of AGCM Simulation Results and Evaluation of their Implications, Quat. Sci. Rev., 19, 881–898, 2000. Yuan, D., Cheng, H., Edwards, R. L., Dykoski, C. A., Kelly, M. J., Zhang, M., Qing, J., Lin, Y., Wang, Y., Wu, J., Dorale, J. A., An, Z., and Cai, Y.: Timing, Duration, and Transitions of the Last Interglacial Asian Monsoon, Science, 304(5670), 575–578, 2004. Zech, R., Glaser, B., Sosin, P., Kubik, P. W., and Zech, W.: Evidence for long-lasting landform surface instability on hummocky moraines in the Pamir Mountains from surface exposure dating, Earth Planet. Sci. Lett., 237, 453–461, 2005. Zech, R., Kull, C., and Veit, H.: Late Quaternary glacial history in the Encierro Valley, Northern Chile (29° S), deduced from 10Be surface exposure dating, Palaeogeography, Palaeoclimatology, Palaeoecology, 234(2–4), 277–286, 2006. Zhou, J. and Lau, K.-M.: Does a monsoon climate exist over South America?, J. Clim., 11(5), 1020–1040, 1998.