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The Deglaciation of the Americas During the Last Glacial Termination

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The Deglaciation of the Americas During the Last Glacial Termination The deglaciation of the Americas during the Last Glacial Termination David Palacios, Chris Stokes, Fred Phillips, John Clague, Jesús Alcalá-Reygosa, Nuria Andrés, Isandra Angel, Pierre-Henri Blard, Jason Briner, Brenda Hall, et al. To cite this version: David Palacios, Chris Stokes, Fred Phillips, John Clague, Jesús Alcalá-Reygosa, et al.. The deglacia- tion of the Americas during the Last Glacial Termination. Earth-Science Reviews, Elsevier, 2020, 203, pp.103113. 10.1016/j.earscirev.2020.103113. hal-02627368 HAL Id: hal-02627368 https://hal-cnrs.archives-ouvertes.fr/hal-02627368 Submitted on 15 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 1 2 3 4 5 1 The Deglaciation of the Americas 6 7 8 9 2 during the Last Glacial Termination 10 11 12 3 13 14 4 David Palacios(1), Chris R. Stokes(2), Fred M. Phillips(3), John J. Clague(4), Jesus Alcalá- 15 5 Reygosa(5), Nuria Andres(1), Isandra Angel(6), Pierre-Henri Blard(7.a,b), Jason P. Briner(8), 16 17 6 Brenda L. Hall(9), Dennis Dahms(10), Andrew S. Hein(11), Vincent Jomelli(12), Bryan G. 18 (13) (14.a,b,c) (15) (16) (17) 19 7 Mark , Mateo A. Martini , Patricio Moreno , Jon Riedel , Esteban Sagredo , 20 8 Nathan D. Stansell(18), Lorenzo Vazquez-Selem(19), Mathias Vuille(20), Dylan J. Ward(21). 21 22 9 23 24 10 (1) Department of Geography, Complutense University, 28040 Madrid, Spain. 25 26 11 (2) Department of Geography, Durham University, Durham, DH1 3LE, UK 27 28 12 3) Earth & Environmental Science Department, New Mexico Institute of Mining & Technology, 801 Leroy 29 13 Place, Socorro NM 87801, USA. 30 31 14 (4) Department of Earth Sciences, Simon Fraser University, 8888 University Dr., Burnaby, Brtish 32 15 Columbia V5A 1S6, Canada. 33 34 16 (5) Facultad de Filosofía y Letras, Universidad Nacional Autónoma de México, Ciudad Universitaria, 35 17 04510 Ciudad de México, México. 36 37 18 (6) Departamento de Ciencias de la Tierra, Universidad Simón Bolívar, 89000, Caracas 1081-A, Venezuela. 38 39 19 (7.a) Centre de Recherches Pétrographiques et Géochimiques (CRPG), UMR 7358, CNRS - Université de 40 20 Lorraine, 15 rue Notre Dame des Pauvres, 54500 Vandoeuvre-lès-Nancy, France. (7.b) Laboratoire de 41 21 Glaciologie, DGES-IGEOS, Université Libre de Bruxelles, 1050 Bruxelles, Belgium. 42 43 22 (8) Department of Geology, University at Buffalo, Buffalo, NY 14260, USA 44 45 23 (9) Department of Earth Sciences and the Climate Change Institute, University of Maine, Orono, ME 46 24 04469, USA 47 48 25 (10) Department of Geography, University of Northern Iowa, Cedar Falls, IA 50614-0406 49 50 26 (11) School of GeoSciences, University of Edinburgh, Drummond Street, Edinburgh, EH8 9XP, UK. 51 52 27 (12) Université Paris 1 Panthéon-Sorbonne, CNRS Laboratoire de Géographie Physique, 92195 Meudon, 53 28 France. 54 55 29 (13) Byrd Polar and Climate Research Center, Ohio State University, 108 Scott Hall 1090 Carmack Rd., 56 30 Columbus, OH 43210 USA 57 58 1 59 60 61 62 31 (14.a) Millennium Nucleus Paleoclimate. Universidad de Chile, Las Palmeras 3425, Ñuñoa, Chile. (14.b) 63 64 32 Instituto de Geografía, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436 65 33 Macul, Chile. (14.c) Centro de Investigaciones en Ciencias de la Tierra (CONICET-Facultad de Ciencias 66 34 Exactas, Físicas y Naturales, UNC), Vélez Sársfled 1611, X5016GCA, Córdoba, Argentina. 67 68 35 (15) Millennium Nucleus Paleoclimate, Center for Climate Research and Resilience, Institute of Ecology 69 36 and Biodiversity, and Department of Ecological Sciences, Universidad de Chile, Las Palmeras 3425, 70 71 37 Ñuñoa, Santiago, Chile 72 38 (16) North Cascades National Park, U.S. National Park Service, SedroWoolley, WA, USA 73 74 39 (17) Millennium Nucleus Paleoclimate and Instituto de Geografía Pontificia Universidad Católica de Chile, 75 76 40 Santiago, Chile 77 41 (18) Geology and Environmental Geosciences, Northern Illinois University, DeKalb, Illinois, IL 60115, 78 79 42 USA 80 43 (19) Instituto de Geografía, Universidad Nacional Autónoma de México, Ciudad Unversitaria, 04510 81 82 44 Ciudad de México, México. 83 84 45 (20) Department of Atmospheric and Environmental Sciences, University at Albany, State University of 85 46 New York (SUNY), Albany, NY 12222, USA 86 87 47 (21) Department of Geology, University of Cincinnati, Cincinnati, OH 45224, USA 88 89 48 90 91 49 Abstract 92 93 50 This paper reviews current understanding of deglaciation in North, Central and South 94 51 America from the Last Glacial Maximum to the beginning of the Holocene. Together 95 96 52 with paleoclimatic and paleoceanographic data, we compare and contrast the pace of 97 deglaciation and the response of glaciers to major climate events. During the Global Last 98 53 99 54 Glacial Maximum (GLGM, 26.5-19 ka), average temperatures decreased 4º to 8ºC in the 100 101 55 Americas, but precipitation varied strongly throughout this large region. Many glaciers 102 56 in North and Central America achieved their maximum extent during the GLGM, whereas 103 104 57 others advanced even farther during the subsequent Heinrich Stadial 1 (HS-1). Glaciers 105 58 in the Andes also expanded during the GLGM, but that advance was not the largest, 106 107 59 except on Tierra del Fuego. HS-1 (17.5-14.6 ka) was a time of general glacier thickening 108 109 60 and advance throughout most of North and Central America, and in the tropical Andes; 110 61 however, glaciers in the temperate and subpolar Andes thinned and retreated during this 111 112 62 period. During the Bølling-Allerød interstadial (B-A, 14.6-12.9 ka), glaciers retreated 113 63 throughout North and Central America and, in some cases, completely disappeared. Many 114 115 64 glaciers advanced during the Antarctic Cold Reversal (ACR, 14.6-12.9 ka) in the tropical 116 117 2 118 119 120 121 65 Andes and Patagonia. There were small advances of glaciers in North America, Central 122 123 66 America and in northern South America (Venezuela) during the Younger Dryas (12.9- 124 125 67 11.7 ka), but glaciers in central and southern South America retreated during this period, 126 68 except on the Altiplano where advances were driven by an increase in precipitation. 127 128 69 Taken together, we suggest that there was a climate compensation effect, or ‘seesaw’, 129 70 between the hemispheres, which affected not only marine currents and atmospheric 130 131 71 circulation, but also the behavior of glaciers. This seesaw is consistent with the opposing 132 133 72 behavior of many glaciers in the Northern and Southern Hemispheres. 134 135 73 Key Words: Deglaciation, Termination-I, Americas, Late Pleistocene, Glacial 136 74 Chronology 137 138 75 139 140 76 1. Introduction 141 142 77 This paper focuses on the evolution of glaciation in the Americas during the Last Glacial 143 144 78 Termination. The American continents extend 15,000 km from 70ºN to 55ºS and are 145 146 79 characterized on their Pacific margins by mountain ranges that are continuous over this 147 80 distance and, in most cases, now have glaciers or had them during the last glacial period 148 149 81 of the Pleistocene. Knowledge of the activity of these glaciers has increased enormously 150 82 in recent years (Palacios, 2017). This knowledge provides us an opportunity to study how 151 152 83 American glaciers behaved during the Last Glacial Termination in the context of the 153 84 asynchronous climatic setting of the two hemispheres. The largely north-south orientation 154 155 85 and nearly continuous extent of mountain ranges in the Americas provide a unique 156 157 86 opportunity to understand synoptic latitudinal variations in global paleoclimate. 158 159 87 The Last Glacial Termination is generally considered to span the time period between the 160 88 Global Last Glacial Maximum (GLGM) and the beginning of the current interglacial 161 162 89 period, the Holocene (Cheng et al., 2009; Denton et al., 2010). It has also been referred 163 to as Termination I, given that it is the last in a series of similar transitions between 164 90 165 91 Pleistocene glacials and interglacials (Emiliani, 1955; Broecker and van Donk, 1970; 166 167 92 Cheng et al., 2009; Deaney et al., 2017). 168 169 93 The motivation for this review paper is that there have been few attempts to summarize, 170 94 synthesize, and compare evidence for late Pleistocene glacier activity across the entire 171 172 95 extent of the Americas. Our objective is to review current understanding of the evolution 173 of glaciers in both North and South America throughout the Last Glacial Termination and 174 96 175 176 3 177 178 179 180 97 discuss whether the contrasts between the hemispheres implied by paleoclimatic and 181 182 98 paleooceanographic models are reflected in the behavior of the glaciers. Given the 183 184 99 continuous nature of the processes involved in the planet’s recent glacial history, parsing 185 100 deglaciation into periods requires simplification of the climatic mechanisms. Different 186 187 101 and opposite changes may occur at different latitudes, with variable response times. In 188 102 the present article, we have however selected deglaciation phases in accordance with the 189 190 103 current state of knowledge and with scientific tradition.
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