1
|
Jansen D, Franke S, Bauer CC, Binder T, Dahl-Jensen D, Eichler J, Eisen O, Hu Y, Kerch J, Llorens MG, Miller H, Neckel N, Paden J, de Riese T, Sachau T, Stoll N, Weikusat I, Wilhelms F, Zhang Y, Bons PD. Shear margins in upper half of Northeast Greenland Ice Stream were established two millennia ago. Nat Commun 2024; 15:1193. [PMID: 38331888 PMCID: PMC10853536 DOI: 10.1038/s41467-024-45021-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 01/09/2024] [Indexed: 02/10/2024] Open
Abstract
Only a few localised ice streams drain most of the ice from the Greenland Ice Sheet. Thus, understanding ice stream behaviour and its temporal variability is crucially important to predict future sea-level change. The interior trunk of the 700 km-long North-East Greenland Ice Stream (NEGIS) is remarkable due to the lack of any clear bedrock channel to explain its presence. Here, we present a 3-dimensional analysis of the folding and advection of its stratigraphic horizons, which shows that the localised flow and shear margins in the upper NEGIS were fully developed only ca 2000 years ago. Our results contradict the assumption that the ice stream has been stable throughout the Holocene in its current form and show that upper NEGIS-type development of ice streaming, with distinct shear margins and no bed topography relationship, can be established on time scales of hundreds of years, which is a major challenge for realistic mass-balance and sea-level rise projections.
Collapse
Affiliation(s)
- Daniela Jansen
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
| | - Steven Franke
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | | | - Tobias Binder
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Now at ATLAS ELEKTRONIK GmbH, Bremen, Germany
| | - Dorthe Dahl-Jensen
- Niels Bohr Institute, Physics of Ice, Climate and Earth, University of Copenhagen, Copenhagen, Denmark
- Center for Earth Observation Sciences, University of Manitoba, Winnipeg, Canada
| | - Jan Eichler
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Now at Laboratoire de Géologie de Lyon: Terre, Planètes, Environnement (LGL-TPE), ENS Lyon, Université Claude Bernard Lyon 1, CNRS, Villeurbanne, France
| | - Olaf Eisen
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- University of Bremen, Bremen, Germany
| | - Yuanbang Hu
- Department of Geosciences, Tübingen University, Tübingen, Germany
- College of Earth Science, Chengdu University of Technology, Chengdu, China
| | - Johanna Kerch
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Geoscience Centre, University of Göttingen, Göttingen, Germany
| | | | - Heinrich Miller
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Niklas Neckel
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - John Paden
- Center for Remote Sensing and Integrated Systems (CReSIS), University of Kansas, Lawrence, KS, USA
| | - Tamara de Riese
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Till Sachau
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Nicolas Stoll
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Now at Department of Environmental Sciences, Informatics and Statistics, Ca'Foscari University Venice, Venice, Italy
| | - Ilka Weikusat
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Frank Wilhelms
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Geoscience Centre, University of Göttingen, Göttingen, Germany
| | - Yu Zhang
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Paul D Bons
- Department of Geosciences, Tübingen University, Tübingen, Germany.
- School of Earth Science and Resources, China University of Geosciences (Beijing), Beijing, China.
| |
Collapse
|
2
|
Christ AJ, Rittenour TM, Bierman PR, Keisling BA, Knutz PC, Thomsen TB, Keulen N, Fosdick JC, Hemming SR, Tison JL, Blard PH, Steffensen JP, Caffee MW, Corbett LB, Dahl-Jensen D, Dethier DP, Hidy AJ, Perdrial N, Peteet DM, Steig EJ, Thomas EK. Deglaciation of northwestern Greenland during Marine Isotope Stage 11. Science 2023; 381:330-335. [PMID: 37471537 DOI: 10.1126/science.ade4248] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 06/21/2023] [Indexed: 07/22/2023]
Abstract
Past interglacial climates with smaller ice sheets offer analogs for ice sheet response to future warming and contributions to sea level rise; however, well-dated geologic records from formerly ice-free areas are rare. Here we report that subglacial sediment from the Camp Century ice core preserves direct evidence that northwestern Greenland was ice free during the Marine Isotope Stage (MIS) 11 interglacial. Luminescence dating shows that sediment just beneath the ice sheet was deposited by flowing water in an ice-free environment 416 ± 38 thousand years ago. Provenance analyses and cosmogenic nuclide data and calculations suggest the sediment was reworked from local materials and exposed at the surface <16 thousand years before deposition. Ice sheet modeling indicates that ice-free conditions at Camp Century require at least 1.4 meters of sea level equivalent contribution from the Greenland Ice Sheet.
Collapse
Affiliation(s)
- Andrew J Christ
- Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA
- Gund Institute for Environment, University of Vermont, Burlington, VT 05405, USA
| | - Tammy M Rittenour
- Department of Geosciences, Utah State University, Logan, UT 84322, USA
| | - Paul R Bierman
- Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA
- Gund Institute for Environment, University of Vermont, Burlington, VT 05405, USA
| | - Benjamin A Keisling
- University of Texas Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78754, USA
| | - Paul C Knutz
- Geological Survey of Denmark and Greenland, 1350 Copenhagen, Denmark
| | - Tonny B Thomsen
- Geological Survey of Denmark and Greenland, 1350 Copenhagen, Denmark
| | - Nynke Keulen
- Geological Survey of Denmark and Greenland, 1350 Copenhagen, Denmark
| | - Julie C Fosdick
- Department of Earth Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Sidney R Hemming
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA
| | - Jean-Louis Tison
- Laboratoire de Glaciologie, DGES-IGEOS, Université Libre de Bruxelles, 1050 Brussels, Belgium
| | - Pierre-Henri Blard
- Laboratoire de Glaciologie, DGES-IGEOS, Université Libre de Bruxelles, 1050 Brussels, Belgium
- Centre de Recherches Pétrographiques et Géochimiques, CNRS, Université de Lorraine, 54500 Nancy, France
| | - Jørgen P Steffensen
- Centre for Ice and Climate, PICE, Niels Bohr Institute, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Marc W Caffee
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907, USA
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Lee B Corbett
- Gund Institute for Environment, University of Vermont, Burlington, VT 05405, USA
| | - Dorthe Dahl-Jensen
- Centre for Ice and Climate, PICE, Niels Bohr Institute, University of Copenhagen, 2200 Copenhagen, Denmark
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - David P Dethier
- Department of Geosciences, Williams College, Williamstown, MA 01267, USA
| | - Alan J Hidy
- Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Nicolas Perdrial
- Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA
- Department of Geography and Geosciences, University of Vermont, Burlington, VT 05405, USA
| | - Dorothy M Peteet
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA
- NASA Goddard Institute for Space Studies, New York, NY 10025, USA
| | - Eric J Steig
- Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195, USA
| | | |
Collapse
|
3
|
Gerber TA, Lilien DA, Rathmann NM, Franke S, Young TJ, Valero-Delgado F, Ershadi MR, Drews R, Zeising O, Humbert A, Stoll N, Weikusat I, Grinsted A, Hvidberg CS, Jansen D, Miller H, Helm V, Steinhage D, O'Neill C, Paden J, Gogineni SP, Dahl-Jensen D, Eisen O. Crystal orientation fabric anisotropy causes directional hardening of the Northeast Greenland Ice Stream. Nat Commun 2023; 14:2653. [PMID: 37156772 PMCID: PMC10167229 DOI: 10.1038/s41467-023-38139-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 04/12/2023] [Indexed: 05/10/2023] Open
Abstract
The dynamic mass loss of ice sheets constitutes one of the biggest uncertainties in projections of ice-sheet evolution. One central, understudied aspect of ice flow is how the bulk orientation of the crystal orientation fabric translates to the mechanical anisotropy of ice. Here we show the spatial distribution of the depth-averaged horizontal anisotropy and corresponding directional flow-enhancement factors covering a large area of the Northeast Greenland Ice Stream onset. Our results are based on airborne and ground-based radar surveys, ice-core observations, and numerical ice-flow modelling. They show a strong spatial variability of the horizontal anisotropy and a rapid crystal reorganisation on the order of hundreds of years coinciding with the ice-stream geometry. Compared to isotropic ice, parts of the ice stream are found to be more than one order of magnitude harder for along-flow extension/compression while the shear margins are potentially softened by a factor of two for horizontal-shear deformation.
Collapse
Affiliation(s)
- Tamara Annina Gerber
- Section for the Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
| | - David A Lilien
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, Canada
| | - Nicholas Mossor Rathmann
- Section for the Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Steven Franke
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Tun Jan Young
- Scott Polar Research Institute, University of Cambridge, Cambridge, United Kingdom
- School of Geography & Sustainable Development, University of St Andrews, St Andrews, KY16 9AL, United Kingdom
| | - Fernando Valero-Delgado
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - M Reza Ershadi
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Reinhard Drews
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Ole Zeising
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Angelika Humbert
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Department of Geosciences, University of Bremen, Bremen, Germany
| | - Nicolas Stoll
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Department of Geosciences, University of Bremen, Bremen, Germany
| | - Ilka Weikusat
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Department of Geosciences, Tübingen University, Tübingen, Germany
| | - Aslak Grinsted
- Section for the Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Christine Schøtt Hvidberg
- Section for the Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Daniela Jansen
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Heinrich Miller
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Veit Helm
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Daniel Steinhage
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | | | - John Paden
- Centre for Remote Sensing and Integrated Systems (CReSIS), University of Kansas, Lawrence, KS, USA
| | | | - Dorthe Dahl-Jensen
- Section for the Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, Canada
| | - Olaf Eisen
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
- Department of Geosciences, University of Bremen, Bremen, Germany.
| |
Collapse
|
4
|
Rathmann NM, Grinsted A, Mosegaard K, Lilien DA, Westhoff J, Hvidberg CS, Prior DJ, Lutz F, Thomas RE, Dahl-Jensen D. Elastic wave propagation in anisotropic polycrystals: inferring physical properties of glacier ice. Proc Math Phys Eng Sci 2022. [DOI: 10.1098/rspa.2022.0574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
An optimization problem is proposed for inferring physical properties of polycrystals given ultrasonic (elastic) wave velocity measurements, made across multiple sample orientations. The feasibility of the method is demonstrated by inferring both the effective grain elastic parameters and the grain
c
-axis orientation distribution function (ODF) of ice-core samples from Priestley glacier, Antarctica. The method relies on expanding the ODF in terms of a spherical harmonic series, which allows for a non-parametric estimation of the sample ODF. Moreover, any linear combination of the Voigt (strain) and Reuss (stress) homogenization scheme is allowed, although for glacier ice, the exact choice is found to matter little for bulk elastic behaviour, and thus for inferred physical properties, too. Finally, the accuracy of the inferred grain elastic parameters is discussed, including the well-posedness and shortcomings of the inverse problem, relevant for future adoptions in glaciology, geology and elsewhere.
Collapse
Affiliation(s)
| | - Aslak Grinsted
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Klaus Mosegaard
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - David A. Lilien
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, Canada
| | - Julien Westhoff
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | | | - David J. Prior
- Department of Geology, University of Otago, Dunedin, New Zealand
| | - Franz Lutz
- Department of Geology, University of Otago, Dunedin, New Zealand
| | - Rilee E. Thomas
- Department of Geology, University of Otago, Dunedin, New Zealand
| | - Dorthe Dahl-Jensen
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, Canada
| |
Collapse
|
5
|
Grinsted A, Hvidberg CS, Lilien DA, Rathmann NM, Karlsson NB, Gerber T, Kjær HA, Vallelonga P, Dahl-Jensen D. Accelerating ice flow at the onset of the Northeast Greenland Ice Stream. Nat Commun 2022; 13:5589. [PMID: 36151072 PMCID: PMC9508143 DOI: 10.1038/s41467-022-32999-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 08/25/2022] [Indexed: 12/05/2022] Open
Abstract
Mass loss near the ice-sheet margin is evident from remote sensing as frontal retreat and increases in ice velocities. Velocities in the ice sheet interior are orders of magnitude smaller, making it challenging to detect velocity change. Here, we analyze a 35-year record of remotely sensed velocities, and a 6-year record of repeated GPS observations, at the East Greenland Ice-core Project (EastGRIP), located in the middle of the Northeast-Greenland Ice Stream (NEGIS). We find that the shear margins of NEGIS are accelerating, indicating a widening of the ice stream. We demonstrate that the widening of the ice stream is unlikely to be a response to recent changes at the outlets of NEGIS. Modelling indicates that the observed spatial fingerprint of acceleration is more consistent with a softening of the shear margin, e.g. due to evolving fabric or temperature, than a response to external forcing at the surface or bed. A new study finds that the North East Greenland ice stream is not as stable as previously thought and that this will affect its future evolution.
Collapse
Affiliation(s)
- Aslak Grinsted
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
| | | | - David A Lilien
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, Canada
| | | | | | - Tamara Gerber
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | | | - Paul Vallelonga
- Oceans Graduate School, The University of Western Australia, Perth, Australia
| | - Dorthe Dahl-Jensen
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.,Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, Canada
| |
Collapse
|
6
|
Fordham DA, Jackson ST, Brown SC, Huntley B, Brook BW, Dahl-Jensen D, Gilbert MTP, Otto-Bliesner BL, Svensson A, Theodoridis S, Wilmshurst JM, Buettel JC, Canteri E, McDowell M, Orlando L, Pilowsky J, Rahbek C, Nogues-Bravo D. Using paleo-archives to safeguard biodiversity under climate change. Science 2020; 369:369/6507/eabc5654. [PMID: 32855310 DOI: 10.1126/science.abc5654] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/30/2020] [Indexed: 12/29/2022]
Abstract
Strategies for 21st-century environmental management and conservation under global change require a strong understanding of the biological mechanisms that mediate responses to climate- and human-driven change to successfully mitigate range contractions, extinctions, and the degradation of ecosystem services. Biodiversity responses to past rapid warming events can be followed in situ and over extended periods, using cross-disciplinary approaches that provide cost-effective and scalable information for species' conservation and the maintenance of resilient ecosystems in many bioregions. Beyond the intrinsic knowledge gain such integrative research will increasingly provide the context, tools, and relevant case studies to assist in mitigating climate-driven biodiversity losses in the 21st century and beyond.
Collapse
Affiliation(s)
- Damien A Fordham
- The Environment Institute and School of Biological Sciences, University of Adelaide, South Australia 5005, Australia. .,Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark
| | - Stephen T Jackson
- Southwest and South Central Climate Adaptation Science Centers, U.S. Geological Survey, Tucson, AZ 85721, USA.,Department of Geosciences and School of Natural Resources and the Environment, University of Arizona, Tucson, AZ 85721, USA
| | - Stuart C Brown
- The Environment Institute and School of Biological Sciences, University of Adelaide, South Australia 5005, Australia
| | - Brian Huntley
- Department of Biosciences, Durham University, Durham, DH1 3LE, UK
| | - Barry W Brook
- School of Natural Sciences and ARC Centre of Excellence for Australian Biodiversity and Heritage, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Dorthe Dahl-Jensen
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen Ø 2100, Denmark.,Centre for Earth Observation Science, University of Manitoba, Winnipeg MB R3T 2N2, Canada
| | - M Thomas P Gilbert
- Center for Evolutionary Hologenomics, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark.,University Museum, Norwegian University of Science and Technology, Trondheim, Norway
| | - Bette L Otto-Bliesner
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO 80307-3000, USA
| | - Anders Svensson
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen Ø 2100, Denmark
| | - Spyros Theodoridis
- Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark
| | - Janet M Wilmshurst
- Long-Term Ecology Laboratory, Manaaki Whenua-Landcare Research, Lincoln 7640, New Zealand.,School of Environment, The University of Auckland, Auckland 1142, New Zealand
| | - Jessie C Buettel
- School of Natural Sciences and ARC Centre of Excellence for Australian Biodiversity and Heritage, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Elisabetta Canteri
- The Environment Institute and School of Biological Sciences, University of Adelaide, South Australia 5005, Australia.,Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark
| | - Matthew McDowell
- School of Natural Sciences and ARC Centre of Excellence for Australian Biodiversity and Heritage, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Ludovic Orlando
- Laboratoire d'Anthropobiologie Moléculaire et d'Imagerie de Synthèse UMR 5288, Université de Toulouse, CNRS, Université Paul Sabatier, France.,Section for GeoGenetics, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark
| | - Julia Pilowsky
- The Environment Institute and School of Biological Sciences, University of Adelaide, South Australia 5005, Australia.,Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark
| | - Carsten Rahbek
- Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark.,Department of Life Sciences, Imperial College London, Ascot SL5 7PY, UK.,Danish Institute for Advanced Study, University of Southern Denmark, Odense, Denmark.,Institute of Ecology, Peking University, Beijing 100871, China
| | - David Nogues-Bravo
- Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen Ø 2100, Denmark
| |
Collapse
|
7
|
Abstract
Fifty years ago, Willi Dansgaard and colleagues discovered several abrupt climate change events in Greenland during the last glacial period. Since then, several ice cores retrieved from the Greenland ice sheet have verified the existence of 25 abrupt climate warming events now known as Dansgaard-Oeschger events. These events are characterized by a rapid 10-15°C warming over a few decades followed by a stable period of centuries or millennia before a gradual return to full glacial conditions. Similar warming events have been identified in other paleo-archives in the Northern hemisphere. These findings triggered wide interest in abrupt climate change and its impact on biological diversity, but ambiguous definitions have constrained our ability to assign biotic responses to the different types of climate change. Here, we provide a coherent definition for different types of climatic change, including 'abrupt climate change', and a summary of past abrupt climate-change events. We then review biotic responses to abrupt climate change, from the genetic to the ecosystem level, and show that abrupt climatic and ecological changes have been instrumental in shaping biodiversity. We also identify open questions, such as what causes species resilience after an abrupt change. However, identifying causal relationships between past climate change and biological responses remains difficult. We need to formalize and unify the definition of abrupt change across disciplines and further investigate past abrupt climate change periods to better anticipate and mitigate the impacts on biodiversity and society wrought by human-made climate change.
Collapse
Affiliation(s)
- Filippo Botta
- Center for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Tagensvej 16, 2200, Copenhagen, Denmark; Center for Macroecology, Evolution and Climate, GLOBE Institute, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark.
| | - Dorthe Dahl-Jensen
- Center for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Tagensvej 16, 2200, Copenhagen, Denmark
| | - Carsten Rahbek
- Center for Macroecology, Evolution and Climate, GLOBE Institute, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark; Department of Life Sciences, Imperial College London, Ascot SL5 7PY, UK; Danish Institute for Advanced Study, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Anders Svensson
- Center for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Tagensvej 16, 2200, Copenhagen, Denmark
| | - David Nogués-Bravo
- Center for Macroecology, Evolution and Climate, GLOBE Institute, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark.
| |
Collapse
|
8
|
Schüpbach S, Fischer H, Bigler M, Erhardt T, Gfeller G, Leuenberger D, Mini O, Mulvaney R, Abram NJ, Fleet L, Frey MM, Thomas E, Svensson A, Dahl-Jensen D, Kettner E, Kjaer H, Seierstad I, Steffensen JP, Rasmussen SO, Vallelonga P, Winstrup M, Wegner A, Twarloh B, Wolff K, Schmidt K, Goto-Azuma K, Kuramoto T, Hirabayashi M, Uetake J, Zheng J, Bourgeois J, Fisher D, Zhiheng D, Xiao C, Legrand M, Spolaor A, Gabrieli J, Barbante C, Kang JH, Hur SD, Hong SB, Hwang HJ, Hong S, Hansson M, Iizuka Y, Oyabu I, Muscheler R, Adolphi F, Maselli O, McConnell J, Wolff EW. Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene. Nat Commun 2018; 9:1476. [PMID: 29662058 PMCID: PMC5902614 DOI: 10.1038/s41467-018-03924-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 03/21/2018] [Indexed: 11/16/2022] Open
Abstract
The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. Separating source and transport effects, we find strongly reduced terrestrial biogenic emissions during glacial times reflecting net loss of vegetated area in North America. Rapid climate changes during the glacial have little effect on terrestrial biogenic aerosol emissions. A strong increase in terrestrial dust emissions during the coldest intervals indicates higher aridity and dust storm activity in East Asian deserts. Glacial sea salt aerosol emissions in the North Atlantic region increase only moderately (50%), likely due to sea ice expansion. Lower aerosol concentrations in Eemian ice compared to the Holocene are mainly due to shortened atmospheric residence time, while emissions changed little. Past climate changes in Greenland ice were accompanied by large aerosol concentration changes. Here, the authors show that by correcting for transport effects, reliable source changes for biogenic aerosol from North America, sea salt aerosol from the North Atlantic, and dust from East Asian deserts can be derived.
Collapse
Affiliation(s)
- S Schüpbach
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - H Fischer
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland.
| | - M Bigler
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - T Erhardt
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - G Gfeller
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - D Leuenberger
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - O Mini
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - R Mulvaney
- British Antarctic Survey, National Environment Research Council, High Cross Madingley Road, Cambridge, CB3 0ET, UK
| | - N J Abram
- British Antarctic Survey, National Environment Research Council, High Cross Madingley Road, Cambridge, CB3 0ET, UK.,Research School of Earth Sciences, The Australian National University, Canberra, ACT 2602, Australia
| | - L Fleet
- British Antarctic Survey, National Environment Research Council, High Cross Madingley Road, Cambridge, CB3 0ET, UK
| | - M M Frey
- British Antarctic Survey, National Environment Research Council, High Cross Madingley Road, Cambridge, CB3 0ET, UK
| | - E Thomas
- British Antarctic Survey, National Environment Research Council, High Cross Madingley Road, Cambridge, CB3 0ET, UK
| | - A Svensson
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - D Dahl-Jensen
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - E Kettner
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - H Kjaer
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - I Seierstad
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - J P Steffensen
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - S O Rasmussen
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - P Vallelonga
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - M Winstrup
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen K, Denmark
| | - A Wegner
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar-und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany
| | - B Twarloh
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar-und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany
| | - K Wolff
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar-und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany
| | - K Schmidt
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar-und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany
| | - K Goto-Azuma
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8518, Japan
| | - T Kuramoto
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8518, Japan.,Fukushima Prefectural Centre for Environmental Creation, 10-2 Fukasaku, Miharu Town, Fukushima, 963-7700, Japan
| | - M Hirabayashi
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8518, Japan
| | - J Uetake
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8518, Japan.,Department of Atmospheric Science, Colorado State University, 200 West Lake Street, 1371 Campus Delivery, Fort Collins, CO, 80523-1371, USA
| | - J Zheng
- Natural Resources Canada, Geological Survey of Canada, 601 Booth Street, Ottawa, K1A 0E8, Canada
| | - J Bourgeois
- Natural Resources Canada, Geological Survey of Canada, 601 Booth Street, Ottawa, K1A 0E8, Canada
| | - D Fisher
- Department of Earth Sciences, Environment and Geomatics, University of Ottawa, Ottawa, ON, Canada
| | - D Zhiheng
- State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - C Xiao
- State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - M Legrand
- Institut des Géosciences de l'Environnement, Université Grenoble Alpes, CS 40 700, 38058, Grenoble Cedex 9, France
| | - A Spolaor
- Institute for the Dynamics of Environmental Processes-CNR, University of Venice, via Torino, 155, 30172, Venice-Mestre, Italy
| | - J Gabrieli
- Institute for the Dynamics of Environmental Processes-CNR, University of Venice, via Torino, 155, 30172, Venice-Mestre, Italy
| | - C Barbante
- Institute for the Dynamics of Environmental Processes-CNR, University of Venice, via Torino, 155, 30172, Venice-Mestre, Italy
| | - J-H Kang
- Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - S D Hur
- Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - S B Hong
- Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - H J Hwang
- Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - S Hong
- Department of Ocean Sciences, Inha University, 100 Inha-ro, Nam-gu, Incheon, 22212, Republic of Korea
| | - M Hansson
- Department of Physical Geography, Stockholm University, S-106 91, Stockholm, Sweden
| | - Y Iizuka
- Department of Physical Geography, Stockholm University, S-106 91, Stockholm, Sweden
| | - I Oyabu
- Department of Physical Geography, Stockholm University, S-106 91, Stockholm, Sweden
| | - R Muscheler
- Department of Geology, Lund University, Solvegatan 12, SE-22362, Lund, Sweden
| | - F Adolphi
- Climate and Environmental Physics, Physics Institute & Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland.,Department of Geology, Lund University, Solvegatan 12, SE-22362, Lund, Sweden
| | - O Maselli
- Desert Research Institute, Nevada System of Higher Education, Reno, NV, 89512, USA
| | - J McConnell
- Desert Research Institute, Nevada System of Higher Education, Reno, NV, 89512, USA
| | - E W Wolff
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, UK
| |
Collapse
|
9
|
Weikusat I, Jansen D, Binder T, Eichler J, Faria SH, Wilhelms F, Kipfstuhl S, Sheldon S, Miller H, Dahl-Jensen D, Kleiner T. Physical analysis of an Antarctic ice core-towards an integration of micro- and macrodynamics of polar ice. Philos Trans A Math Phys Eng Sci 2017; 375:rsta.2015.0347. [PMID: 28025296 PMCID: PMC5179957 DOI: 10.1098/rsta.2015.0347] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/02/2016] [Indexed: 06/06/2023]
Abstract
Microstructures from deep ice cores reflect the dynamic conditions of the drill location as well as the thermodynamic history of the drill site and catchment area in great detail. Ice core parameters (crystal lattice-preferred orientation (LPO), grain size, grain shape), mesostructures (visual stratigraphy) as well as borehole deformation were measured in a deep ice core drilled at Kohnen Station, Dronning Maud Land (DML), Antarctica. These observations are used to characterize the local dynamic setting and its rheological as well as microstructural effects at the EDML ice core drilling site (European Project for Ice Coring in Antarctica in DML). The results suggest a division of the core into five distinct sections, interpreted as the effects of changing deformation boundary conditions from triaxial deformation with horizontal extension to bedrock-parallel shear. Region 1 (uppermost approx. 450 m depth) with still small macroscopic strain is dominated by compression of bubbles and strong strain and recrystallization localization. Region 2 (approx. 450-1700 m depth) shows a girdle-type LPO with the girdle plane being perpendicular to grain elongations, which indicates triaxial deformation with dominating horizontal extension. In this region (approx. 1000 m depth), the first subtle traces of shear deformation are observed in the shape-preferred orientation (SPO) by inclination of the grain elongation. Region 3 (approx. 1700-2030 m depth) represents a transitional regime between triaxial deformation and dominance of shear, which becomes apparent in the progression of the girdle to a single maximum LPO and increasing obliqueness of grain elongations. The fully developed single maximum LPO in region 4 (approx. 2030-2385 m depth) is an indicator of shear dominance. Region 5 (below approx. 2385 m depth) is marked by signs of strong shear, such as strong SPO values of grain elongation and strong kink folding of visual layers. The details of structural observations are compared with results from a numerical ice sheet model (PISM, isotropic) for comparison of strain rate trends predicted from the large-scale geometry of the ice sheet and borehole logging data. This comparison confirms the segmentation into these depth regions and in turn provides a wider view of the ice sheet.This article is part of the themed issue 'Microdynamics of ice'.
Collapse
Affiliation(s)
- Ilka Weikusat
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
- Department of Geosciences, Eberhard Karls University, Tübingen, Germany
| | - Daniela Jansen
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Tobias Binder
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Jan Eichler
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Sérgio H Faria
- BC3-Basque Centre for Climate Change, Ikerbasque, Bilbao, Spain
- NUT-Nagaoka University of Technology Nagaoka, Niigata, Japan
| | - Frank Wilhelms
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
- Georg-August-Universität Göttingen, Göttingen, Germany
| | - Sepp Kipfstuhl
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Simon Sheldon
- CIC, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Heinrich Miller
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Dorthe Dahl-Jensen
- CIC, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Kleiner
- AWI-Glaciology, Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| |
Collapse
|
10
|
Sturevik-Storm A, Aldahan A, Possnert G, Berggren AM, Muscheler R, Dahl-Jensen D, Vinther BM, Usoskin I. 10Be climate fingerprints during the Eemian in the NEEM ice core, Greenland. Sci Rep 2014; 4:6408. [PMID: 25266953 PMCID: PMC4179124 DOI: 10.1038/srep06408] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 08/19/2014] [Indexed: 11/09/2022] Open
Abstract
Several deep Greenland ice cores have been retrieved, however, capturing the Eemian period has been problematic due to stratigraphic disturbances in the ice. The new Greenland deep ice core from the NEEM site (77.45 °N, 51.06 °W, 2450 m.a.s.l) recovered a relatively complete Eemian record. Here we discuss the cosmogenic (10)Be isotope record from this core. The results show Eemian average (10)Be concentrations about 0.7 times lower than in the Holocene which suggests a warmer climate and approximately 65-90% higher precipitation in Northern Greenland compared to today. Effects of shorter solar variations on (10)Be concentration are smoothed out due to coarse time resolution, but occurrence of a solar maximum at 115.26-115.36 kyr BP is proposed. Relatively high (10)Be concentrations are found in the basal ice sections of the core which may originate from the glacial-interglacial transition and relate to a geomagnetic excursion about 200 kyr BP.
Collapse
Affiliation(s)
- Anna Sturevik-Storm
- Uppsala University, Department of Earth Sciences, Villavägen 16 B, 752 36 Uppsala, Sweden
| | - Ala Aldahan
- 1] Uppsala University, Department of Earth Sciences, Villavägen 16 B, 752 36 Uppsala, Sweden [2] Department of Geology, United Arab Emirates University, Al Ain, UAE
| | - Göran Possnert
- Tandem Laboratory, Uppsala University, Lägerhyddsvägen 1, 751 20 Uppsala, Sweden
| | - Ann-Marie Berggren
- Uppsala University, Department of Earth Sciences, Villavägen 16 B, 752 36 Uppsala, Sweden
| | - Raimund Muscheler
- Department of Geology, Lund University, Sölvegatan 12, 223 62 Lund, Sweden
| | - Dorthe Dahl-Jensen
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen K, Denmark
| | - Bo M Vinther
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen K, Denmark
| | - Ilya Usoskin
- Sodankylä Geophysical Observatory (Oulu unit) and Physics Dept., 90014 University of Oulu, Finland
| |
Collapse
|
11
|
|
12
|
Vincent WF, Callaghan TV, Dahl-Jensen D, Johansson M, Kovacs KM, Michel C, Prowse T, Reist JD, Sharp M. Ecological Implications of Changes in the Arctic Cryosphere. Ambio 2011; 40:87-99. [PMCID: PMC3357775 DOI: 10.1007/s13280-011-0218-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Snow, water, ice, and permafrost are showing evidence of substantial change in the Arctic, with large variations among different geographical areas. As a result of these changes, some habitats and their associated ecosystems are expanding, while others are undergoing rapid contraction. The warming of the Arctic cryosphere is limiting the range for cold-adapted biota, and less specialized taxa including invasive species from the south are likely to become increasingly common. Extreme climate events such as winter thawing are likely to become more frequent, and may accelerate shifts in community structure and processes. Many Arctic ecosystems are interdependent, and changes in the cryosphere are altering physical, biogeochemical, and biological linkages, as well as causing positive feedback effects on atmospheric warming. All of these climate-related effects are compounded by rapid socio-economic development in the North, creating additional challenges for northern communities and indigenous lifestyles that depend on Arctic ecosystem services.
Collapse
Affiliation(s)
- Warwick F. Vincent
- Département de Biologie & Centre d’Études Nordiques (CEN), Laval University, Québec City, QC G1V 0A6 Canada
| | | | - Dorthe Dahl-Jensen
- Niels Bohr Institutet, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Margareta Johansson
- Department of Earth and Ecosystem Sciences, Division of Physical Geography and Ecosystem Analyses, Lund University, Sölvegatan 12, 223 62 Lund, Sweden
| | | | - Christine Michel
- Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB R3T 2N6 Canada
| | - Terry Prowse
- Environment Canada, Department of Geography, University of Victoria, Victoria, BC V8P 5C2 Canada
| | - James D. Reist
- Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB R3T 2N6 Canada
| | - Martin Sharp
- Earth and Atmospheric Sciences, University of Alberta, Edmonton AB, T6G 2E3 Canada
| |
Collapse
|
13
|
Olsen MS, Callaghan TV, Reist JD, Reiersen LO, Dahl-Jensen D, Granskog MA, Goodison B, Hovelsrud GK, Johansson M, Kallenborn R, Key J, Klepikov A, Meier W, Overland JE, Prowse TD, Sharp M, Vincent WF, Walsh J. The Changing Arctic Cryosphere and Likely Consequences: An Overview. Ambio 2011. [PMID: 0 PMCID: PMC3357772 DOI: 10.1007/s13280-011-0220-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The Arctic cryosphere is a critically important component of the earth system, affecting the energy balance, atmospheric and ocean circulation, freshwater storage, sea level, the storage, and release of large quantities of greenhouse gases, economy, infrastructure, health, and indigenous and non-indigenous livelihoods, culture and identity. Currently, components of the Arctic cryosphere are subjected to dramatic change due to global warming. The need to document, understand, project, and respond to changes in the cryosphere and their consequences stimulated a comprehensive international assessment called “SWIPA”: Snow, Water, Ice, Permafrost in the Arctic. Some of the extensive key SWIPA chapters have been summarized and made more widely available to a global audience with multi-disciplinary interests in this Special Report of Ambio. In this article, an overview is provided of this Special Report in the context of the more detailed and wider scope of the SWIPA Report. Accelerated changes in major components of the Arctic cryosphere are documented. Evidence of feedback mechanisms between the cryosphere and other parts of the climate system are identified as contributing factors to enhanced Arctic warming while the growing importance of Arctic land-based ice as a contributor to global sea-level rise is quantified. Cryospheric changes will result in multifaceted and cascading effects for people within and beyond the Arctic presenting both challenges and opportunities.
Collapse
Affiliation(s)
- M. S. Olsen
- Danish Energy Agency, Amaliegade 44, 1256 Copenhagen, Denmark
| | | | - J. D. Reist
- Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB R3T 2N6 Canada
| | | | - D. Dahl-Jensen
- Niels Bohr Institutet, University of Copenhagen, 2100 Copenhagen, Denmark
| | - M. A. Granskog
- Norwegian Polar Institute, Fram Centre, 9296 Tromsø, Norway
| | - B. Goodison
- World Meteorological Organization, 7 bis, Avenue de la Paix, Case Postale 2300, 1211 Geneva, Switzerland
| | - G. K. Hovelsrud
- Nordland Research Institute, P.O. Box 1490, 8049 Bodø, Norway
| | - M. Johansson
- Division of Physical Geography and Ecosystem Analyses, Department of Earth and Ecosystem Sciences, Lund University, Sölvegatan 12, 223 62 Lund, Sweden
| | - R. Kallenborn
- Department of Chemistry, Biotechnology and Food Science (IKBM), Norwegian University of Life Sciences (UMB), Christian Magnus Falsen vei 1, Postbox 5003, 1432 Ås, Norway
| | - J. Key
- NOAA/NESDIS, 1225 West Dayton Street, Madison, WI 53706 USA
| | - A. Klepikov
- Arctic and Antarctic Research Institute, 38 Bering Street, St. Petersburg, Russia 199397
| | - W. Meier
- NSIDC, University of Colorado, 449 UCB, Boulder, CO 80309 USA
| | - J. E. Overland
- Pacific Marine Environmental Laboratory, NOAA, Seattle, WA USA
| | - T. D. Prowse
- Environment Canada, Victoria, BC Canada
- Department of Geography, University of Victoria, Victoria, BC V8P 5C2 Canada
| | - M. Sharp
- Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3 Canada
| | - W. F. Vincent
- Département de Biologie & Centre d’Études Nordiques (CEN), Laval University, Quebec, QC G1V 0A6 Canada
| | - J. Walsh
- International Arctic Research Center, University of Alaska, Fairbanks, AK USA
| |
Collapse
|
14
|
Steen-Larsen HC, Masson-Delmotte V, Sjolte J, Johnsen SJ, Vinther BM, Bréon FM, Clausen HB, Dahl-Jensen D, Falourd S, Fettweis X, Gallée H, Jouzel J, Kageyama M, Lerche H, Minster B, Picard G, Punge HJ, Risi C, Salas D, Schwander J, Steffen K, Sveinbjörnsdóttir AE, Svensson A, White J. Understanding the climatic signal in the water stable isotope records from the NEEM shallow firn/ice cores in northwest Greenland. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014311] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
15
|
Andersen ML, Larsen TB, Nettles M, Elosegui P, van As D, Hamilton GS, Stearns LA, Davis JL, Ahlstrøm AP, de Juan J, Ekström G, Stenseng L, Khan SA, Forsberg R, Dahl-Jensen D. Spatial and temporal melt variability at Helheim Glacier, East Greenland, and its effect on ice dynamics. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jf001760] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
16
|
Vinther BM, Clausen HB, Johnsen SJ, Rasmussen SO, Steffensen JP, Andersen KK, Buchardt SL, Dahl-Jensen D, Seierstad IK, Svensson AM, Siggaard-Andersen ML, Olsen J, Heinemeier J. Reply to comment by J. S. Denton and N. J. G. Pearce on “A synchronized dating of three Greenland ice cores throughout the Holocene”. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009083] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
17
|
Steffensen JP, Andersen KK, Bigler M, Clausen HB, Dahl-Jensen D, Fischer H, Goto-Azuma K, Hansson M, Johnsen SJ, Jouzel J, Masson-Delmotte V, Popp T, Rasmussen SO, Röthlisberger R, Ruth U, Stauffer B, Siggaard-Andersen ML, Sveinbjörnsdóttir AE, Svensson A, White JWC. High-resolution Greenland ice core data show abrupt climate change happens in few years. Science 2008; 321:680-4. [PMID: 18566247 DOI: 10.1126/science.1157707] [Citation(s) in RCA: 653] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The last two abrupt warmings at the onset of our present warm interglacial period, interrupted by the Younger Dryas cooling event, were investigated at high temporal resolution from the North Greenland Ice Core Project ice core. The deuterium excess, a proxy of Greenland precipitation moisture source, switched mode within 1 to 3 years over these transitions and initiated a more gradual change (over 50 years) of the Greenland air temperature, as recorded by stable water isotopes. The onsets of both abrupt Greenland warmings were slightly preceded by decreasing Greenland dust deposition, reflecting the wetting of Asian deserts. A northern shift of the Intertropical Convergence Zone could be the trigger of these abrupt shifts of Northern Hemisphere atmospheric circulation, resulting in changes of 2 to 4 kelvin in Greenland moisture source temperature from one year to the next.
Collapse
Affiliation(s)
- Jørgen Peder Steffensen
- Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen OE, Denmark.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Vinther BM, Clausen HB, Fisher DA, Koerner RM, Johnsen SJ, Andersen KK, Dahl-Jensen D, Rasmussen SO, Steffensen JP, Svensson AM. Synchronizing ice cores from the Renland and Agassiz ice caps to the Greenland Ice Core Chronology. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009143] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
19
|
Iizuka Y, Horikawa S, Sakurai T, Johnson S, Dahl-Jensen D, Steffensen JP, Hondoh T. A relationship between ion balance and the chemical compounds of salt inclusions found in the Greenland Ice Core Project and Dome Fuji ice cores. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009018] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
20
|
Willerslev E, Cappellini E, Boomsma W, Nielsen R, Hebsgaard MB, Brand TB, Hofreiter M, Bunce M, Poinar HN, Dahl-Jensen D, Johnsen S, Steffensen JP, Bennike O, Schwenninger JL, Nathan R, Armitage S, de Hoog CJ, Alfimov V, Christl M, Beer J, Muscheler R, Barker J, Sharp M, Penkman KEH, Haile J, Taberlet P, Gilbert MTP, Casoli A, Campani E, Collins MJ. Ancient biomolecules from deep ice cores reveal a forested southern Greenland. Science 2007; 317:111-4. [PMID: 17615355 PMCID: PMC2694912 DOI: 10.1126/science.1141758] [Citation(s) in RCA: 333] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
It is difficult to obtain fossil data from the 10% of Earth's terrestrial surface that is covered by thick glaciers and ice sheets, and hence, knowledge of the paleoenvironments of these regions has remained limited. We show that DNA and amino acids from buried organisms can be recovered from the basal sections of deep ice cores, enabling reconstructions of past flora and fauna. We show that high-altitude southern Greenland, currently lying below more than 2 kilometers of ice, was inhabited by a diverse array of conifer trees and insects within the past million years. The results provide direct evidence in support of a forested southern Greenland and suggest that many deep ice cores may contain genetic records of paleoenvironments in their basal sections.
Collapse
Affiliation(s)
- Eske Willerslev
- Centre for Ancient Genetics, University of Copenhagen, Denmark.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
|
22
|
Fisher DA, Wake C, Kreutz K, Yalcin K, Steig E, Mayewski P, Anderson L, Zheng J, Rupper S, Zdanowicz C, Demuth M, Waszkiewicz M, Dahl-Jensen D, Goto-Azuma K, Bourgeois JB, Koerner RM, Sekerka J, Osterberg E, Abbott MB, Finney BP, Burns SJ. Stable Isotope Records from Mount Logan, Eclipse Ice Cores and Nearby Jellybean Lake. Water Cycle of the North Pacific Over 2000 Years and Over Five Vertical Kilometres: Sudden Shifts and Tropical Connections. ACTA ACUST UNITED AC 2006. [DOI: 10.7202/013147ar] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Abstract
Three ice cores recovered on or near Mount Logan, together with a nearby lake record (Jellybean Lake), cover variously 500 to 30 000 years. This suite of records offers a unique view of the lapse rate in stable isotopes from the lower to upper troposphere. The region is climatologically important, being beside the Cordilleran pinning-point of the Rossby Wave system and the Aleutian Low. Comparison of stable isotope series over the last 2000 years and model simulations suggest sudden and persistent shifts between modern (mixed) and zonal flow regimes of water vapour transport to the Pacific Northwest. The last such shift was in A.D. 1840. Model simulations for modern and “pure” zonal flow suggest that these shifts are consistent regime changes between these flow types, with predominantly zonal flow prior to ca. A.D. 1840 and modern thereafter. The 5.4 and 0.8 km asl records show a shift at A.D. 1840 and another at A.D. 800. It is speculated that the A.D. 1840 regime shift coincided with the end of the Little Ice Age and the A.D. 800 shift with the beginning of the European Medieval Warm Period. The shifts are very abrupt, taking only a few years at most.
Collapse
Affiliation(s)
- D. A. Fisher
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | - C. Wake
- Climate Change Research Center, Morse Hall, University of New Hampshire, Durham, New Hampshire 03824, United States
| | - K. Kreutz
- Climate Change Institute and Department of Earth Sciences, University of Maine, Orono, Maine 04469, United States
| | - K. Yalcin
- Climate Change Research Center, Morse Hall, University of New Hampshire, Durham, New Hampshire 03824, United States
| | - E. Steig
- Quaternary Research Center, 19 Johnson Hall, Box 1360, University of Washington, Seattle, Washington 98195, United States
| | - P. Mayewski
- Climate Change Institute and Department of Earth Sciences, University of Maine, Orono, Maine 04469, United States
| | - L. Anderson
- Department of Geosciences, University of Massachusetts-Amherst, Amherst, Massachusetts 01003, United States
| | - J. Zheng
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | - S. Rupper
- Quaternary Research Center, 19 Johnson Hall, Box 1360, University of Washington, Seattle, Washington 98195, United States
| | - C. Zdanowicz
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | - M. Demuth
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | | | - D. Dahl-Jensen
- Niels Bohr Institute, Juliane Maries Vej 30, University of Copenhagen, DK‑2100, Copenhagen East, Danemark
| | - K. Goto-Azuma
- National Institute of Polar Research, Tokyo 173‑8515, Japan
| | - J. B. Bourgeois
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | - R. M. Koerner
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | - J. Sekerka
- Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8
| | - E. Osterberg
- Climate Change Institute and Department of Earth Sciences, University of Maine, Orono, Maine 04469, United States
| | - M. B. Abbott
- Department of Geology and Planetary Science, University of Pittsburg; Pittsburg, Pennsylvania 15260; United States
| | - B. P. Finney
- Institute of Marine Sciences, University of Alaska Fairbanks, Fairbanks, Alaska 99775, United States
| | - S. J. Burns
- Department of Geosciences, University of Massachusetts-Amherst, Amherst, Massachusetts 01003, United States
| |
Collapse
|
23
|
Vinther BM, Clausen HB, Johnsen SJ, Rasmussen SO, Andersen KK, Buchardt SL, Dahl-Jensen D, Seierstad IK, Siggaard-Andersen ML, Steffensen JP, Svensson A, Olsen J, Heinemeier J. A synchronized dating of three Greenland ice cores throughout the Holocene. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006921] [Citation(s) in RCA: 433] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
24
|
Rasmussen SO, Andersen KK, Svensson AM, Steffensen JP, Vinther BM, Clausen HB, Siggaard-Andersen ML, Johnsen SJ, Larsen LB, Dahl-Jensen D, Bigler M, Röthlisberger R, Fischer H, Goto-Azuma K, Hansson ME, Ruth U. A new Greenland ice core chronology for the last glacial termination. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006079] [Citation(s) in RCA: 1250] [Impact Index Per Article: 69.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
25
|
Masson-Delmotte V, Landais A, Stievenard M, Cattani O, Falourd S, Jouzel J, Johnsen SJ, Dahl-Jensen D, Sveinsbjornsdottir A, White JWC, Popp T, Fischer H. Holocene climatic changes in Greenland: Different deuterium excess signals at Greenland Ice Core Project (GRIP) and NorthGRIP. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004jd005575] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- V. Masson-Delmotte
- l'Institut Pierre-Simon Laplace/Commissariat à l'Energie Atomique; CNRS Laboratoire des Sciences du Climat et de l'Environnement; Gif-sur-Yvette France
| | - A. Landais
- l'Institut Pierre-Simon Laplace/Commissariat à l'Energie Atomique; CNRS Laboratoire des Sciences du Climat et de l'Environnement; Gif-sur-Yvette France
| | - M. Stievenard
- l'Institut Pierre-Simon Laplace/Commissariat à l'Energie Atomique; CNRS Laboratoire des Sciences du Climat et de l'Environnement; Gif-sur-Yvette France
| | - O. Cattani
- l'Institut Pierre-Simon Laplace/Commissariat à l'Energie Atomique; CNRS Laboratoire des Sciences du Climat et de l'Environnement; Gif-sur-Yvette France
| | - S. Falourd
- l'Institut Pierre-Simon Laplace/Commissariat à l'Energie Atomique; CNRS Laboratoire des Sciences du Climat et de l'Environnement; Gif-sur-Yvette France
| | - J. Jouzel
- l'Institut Pierre-Simon Laplace/Commissariat à l'Energie Atomique; CNRS Laboratoire des Sciences du Climat et de l'Environnement; Gif-sur-Yvette France
| | - S. J. Johnsen
- Niels Bohr Institute; University of Copenhagen; Copenhagen Denmark
| | - D. Dahl-Jensen
- Niels Bohr Institute; University of Copenhagen; Copenhagen Denmark
| | | | - J. W. C. White
- Geological Sciences Department; University of Colorado; Boulder Colorado USA
| | - T. Popp
- Geological Sciences Department; University of Colorado; Boulder Colorado USA
| | - H. Fischer
- Alfred Wegener Institute for Polar and Marine Research; Bremerhaven Germany
| |
Collapse
|
26
|
Andersen KK, Azuma N, Barnola JM, Bigler M, Biscaye P, Caillon N, Chappellaz J, Clausen HB, Dahl-Jensen D, Fischer H, Flückiger J, Fritzsche D, Fujii Y, Goto-Azuma K, Grønvold K, Gundestrup NS, Hansson M, Huber C, Hvidberg CS, Johnsen SJ, Jonsell U, Jouzel J, Kipfstuhl S, Landais A, Leuenberger M, Lorrain R, Masson-Delmotte V, Miller H, Motoyama H, Narita H, Popp T, Rasmussen SO, Raynaud D, Rothlisberger R, Ruth U, Samyn D, Schwander J, Shoji H, Siggard-Andersen ML, Steffensen JP, Stocker T, Sveinbjörnsdóttir AE, Svensson A, Takata M, Tison JL, Thorsteinsson T, Watanabe O, Wilhelms F, White JWC. High-resolution record of Northern Hemisphere climate extending into the last interglacial period. Nature 2004; 431:147-51. [PMID: 15356621 DOI: 10.1038/nature02805] [Citation(s) in RCA: 313] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2004] [Accepted: 06/30/2004] [Indexed: 11/08/2022]
Abstract
Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time.
Collapse
Affiliation(s)
- K K Andersen
- Niels Bohr Institute for Astronomy, Physics and Geophysics, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen OE, Denmark
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Augustin L, Barbante C, Barnes PRF, Barnola JM, Bigler M, Castellano E, Cattani O, Chappellaz J, Dahl-Jensen D, Delmonte B, Dreyfus G, Durand G, Falourd S, Fischer H, Flückiger J, Hansson ME, Huybrechts P, Jugie G, Johnsen SJ, Jouzel J, Kaufmann P, Kipfstuhl J, Lambert F, Lipenkov VY, Littot GC, Longinelli A, Lorrain R, Maggi V, Masson-Delmotte V, Miller H, Mulvaney R, Oerlemans J, Oerter H, Orombelli G, Parrenin F, Peel DA, Petit JR, Raynaud D, Ritz C, Ruth U, Schwander J, Siegenthaler U, Souchez R, Stauffer B, Steffensen JP, Stenni B, Stocker TF, Tabacco IE, Udisti R, Van De Wal RSW, Van Den Broeke M, Weiss J, Wilhelms F, Winther JG, Wolff EW, Zucchelli M. Eight glacial cycles from an Antarctic ice core. Nature 2004; 429:623-8. [PMID: 15190344 DOI: 10.1038/nature02599] [Citation(s) in RCA: 323] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Accepted: 04/22/2004] [Indexed: 11/09/2022]
Abstract
The Antarctic Vostok ice core provided compelling evidence of the nature of climate, and of climate feedbacks, over the past 420,000 years. Marine records suggest that the amplitude of climate variability was smaller before that time, but such records are often poorly resolved. Moreover, it is not possible to infer the abundance of greenhouse gases in the atmosphere from marine records. Here we report the recovery of a deep ice core from Dome C, Antarctica, that provides a climate record for the past 740,000 years. For the four most recent glacial cycles, the data agree well with the record from Vostok. The earlier period, between 740,000 and 430,000 years ago, was characterized by less pronounced warmth in interglacial periods in Antarctica, but a higher proportion of each cycle was spent in the warm mode. The transition from glacial to interglacial conditions about 430,000 years ago (Termination V) resembles the transition into the present interglacial period in terms of the magnitude of change in temperatures and greenhouse gases, but there are significant differences in the patterns of change. The interglacial stage following Termination V was exceptionally long--28,000 years compared to, for example, the 12,000 years recorded so far in the present interglacial period. Given the similarities between this earlier warm period and today, our results may imply that without human intervention, a climate similar to the present one would extend well into the future.
Collapse
Affiliation(s)
- Laurent Augustin
- Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS, BP 96, 38402 St Martin d'Hères Cedex, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Abstract
The Greenland Ice Sheet holds a substantial part of Earth's fresh water, and melting of the sheet contributes to sea level rise. Dahl-Jensen discusses the reports by Krabill et al. and Thomas et al., which shed light on short- and long-term surface elevation changes of the ice sheet. Low-altitude areas are melting, but high-altitude areas show no net reduction over both the short and the long term.
Collapse
|
29
|
Clifford SM, Crisp D, Fisher DA, Herkenhoff KE, Smrekar SE, Thomas PC, Wynn-Williams DD, Zurek RW, Barnes JR, Bills BG, Blake EW, Calvin WM, Cameron JM, Carr MH, Christensen PR, Clark BC, Clow GD, Cutts JA, Dahl-Jensen D, Durham WB, Fanale FP, Farmer JD, Forget F, Gotto-Azuma K, Zwally HJ. The state and future of Mars polar science and exploration. Icarus 2000; 144:210-242. [PMID: 11543391 DOI: 10.1006/icar.1999.6290] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of approximately 10(6) km2 and total as much as 3-4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young--preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust over the past approximately 10(5)-10(8) years. For this reason, the martian polar deposits may serve as a Rosetta Stone for understanding the geologic and climatic history of the planet--documenting variations in insolation (due to quasiperiodic oscillations in the planet's obliquity and orbital elements), volatile mass balance, atmospheric composition, dust storm activity, volcanic eruptions, large impacts, catastrophic floods, solar luminosity, supernovae, and perhaps even a record of microbial life. Beyond their scientific value, the polar regions may soon prove important for another reason--providing a valuable and accessible reservoir of water to support the long-term human exploration of Mars. In this paper we assess the current state of Mars polar research, identify the key questions that motivate the exploration of the polar regions, discuss the extent to which current missions will address these questions, and speculate about what additional capabilities and investigations may be required to address the issues that remain outstanding.
Collapse
Affiliation(s)
- S M Clifford
- Lunar and Planetary Institute, Houston, Texas 77058, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Abstract
A Monte Carlo inverse method has been used on the temperature profiles measured down through the Greenland Ice Core Project (GRIP) borehole, at the summit of the Greenland Ice Sheet, and the Dye 3 borehole 865 kilometers farther south. The result is a 50, 000-year-long temperature history at GRIP and a 7000-year history at Dye 3. The Last Glacial Maximum, the Climatic Optimum, the Medieval Warmth, the Little Ice Age, and a warm period at 1930 A.D. are resolved from the GRIP reconstruction with the amplitudes -23 kelvin, +2.5 kelvin, +1 kelvin, -1 kelvin, and +0.5 kelvin, respectively. The Dye 3 temperature is similar to the GRIP history but has an amplitude 1.5 times larger, indicating higher climatic variability there. The calculated terrestrial heat flow density from the GRIP inversion is 51.3 milliwatts per square meter.
Collapse
Affiliation(s)
- D Dahl-Jensen
- D. Dahl-Jensen, K. Mosegaard, N. Gundestrup, S. J. Johnsen, A. W. Hansen, Niels Bohr Institute for Astronomy, Physics and Geophysics, Department of Geophysics, Juliane Maries Vej 30, DK-2100 Copenhagen OE, Denmark. G. D. Clow, USGS-Climate Program
| | | | | | | | | | | | | |
Collapse
|
31
|
Johnsen SJ, Clausen HB, Dansgaard W, Gundestrup NS, Hammer CU, Andersen U, Andersen KK, Hvidberg CS, Dahl-Jensen D, Steffensen JP, Shoji H, Sveinbjörnsdóttir ÁE, White J, Jouzel J, Fisher D. The δ18O record along the Greenland Ice Core Project deep ice core and the problem of possible Eemian climatic instability. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jc00167] [Citation(s) in RCA: 391] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
32
|
Dahl-Jensen D, Thorsteinsson T, Alley R, Shoji H. Flow properties of the ice from the Greenland Ice Core Project ice core: The reason for folds? ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jc01266] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
33
|
Hvidberg CS, Dahl-Jensen D, Waddington ED. Ice flow between the Greenland Ice Core Project and Greenland Ice Sheet Project 2 boreholes in central Greenland. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jc00268] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
34
|
Clausen HB, Hammer CU, Hvidberg CS, Dahl-Jensen D, Steffensen JP, Kipfstuhl J, Legrand M. A comparison of the volcanic records over the past 4000 years from the Greenland Ice Core Project and Dye 3 Greenland ice cores. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jc00587] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
35
|
Taylor KC, Hammer CU, Alley RB, Clausen HB, Dahl-Jensen D, Gow AJ, Gundestrup NS, Kipfstuh J, Moore JC, Waddington ED. Electrical conductivity measurements from the GISP2 and GRIP Greenland ice cores. Nature 1993. [DOI: 10.1038/366549a0] [Citation(s) in RCA: 218] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
36
|
Dansgaard W, Johnsen SJ, Clausen HB, Dahl-Jensen D, Gundestrup NS, Hammer CU, Hvidberg CS, Steffensen JP, Sveinbjörnsdottir AE, Jouzel J, Bond G. Evidence for general instability of past climate from a 250-kyr ice-core record. Nature 1993. [DOI: 10.1038/364218a0] [Citation(s) in RCA: 3455] [Impact Index Per Article: 111.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
37
|
Dansgaard W, Johnsen S, Clausen H, Dahl-Jensen D, Gundestrup N, Hammer C, Oeschger H. North Atlantic climatic oscillations revealed by deep Greenland ice cores. Climate Processes and Climate Sensitivity 1984. [DOI: 10.1029/gm029p0288] [Citation(s) in RCA: 165] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
|