Antarctic Ice Sheet Balance Velocities from Merged Point and Vector Data Abstract
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Early Break-Up of the Norwegian Channel Ice Stream During the Last Glacial Maximum
Quaternary Science Reviews 107 (2015) 231e242 Contents lists available at ScienceDirect Quaternary Science Reviews journal homepage: www.elsevier.com/locate/quascirev Early break-up of the Norwegian Channel Ice Stream during the Last Glacial Maximum * John Inge Svendsen a, , Jason P. Briner b, Jan Mangerud a, Nicolas E. Young c a Department of Earth Science, University of Bergen and Bjerknes Centre for Climate Research, Postbox 7803, N-5020 Bergen, Norway b Department of Geology, University at Buffalo, Buffalo, NY 14260, USA c Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA article info abstract Article history: We present 18 new cosmogenic 10Be exposure ages that constrain the breakup time of the Norwegian Received 11 June 2014 Channel Ice Stream (NCIS) and the initial retreat of the Scandinavian Ice Sheet from the Southwest coast Received in revised form of Norway following the Last Glacial Maximum (LGM). Seven samples from glacially transported erratics 31 October 2014 on the island Utsira, located in the path of the NCIS about 400 km up-flow from the LGM ice front Accepted 3 November 2014 position, yielded an average 10Be age of 22.0 ± 2.0 ka. The distribution of the ages is skewed with the 4 Available online youngest all within the range 20.2e20.8 ka. We place most confidence on this cluster of ages to constrain the timing of ice sheet retreat as we suspect the 3 oldest ages have some inheritance from a previous ice Keywords: Norwegian Channel Ice Stream free period. Three additional ages from the adjacent island Karmøy provided an average age of ± 10 Scandinavian Ice Sheet 20.9 0.7 ka, further supporting the new timing of retreat for the NCIS. -
Ribbed Bedforms in Palaeo-Ice Streams Reveal Shear Margin
https://doi.org/10.5194/tc-2020-336 Preprint. Discussion started: 21 November 2020 c Author(s) 2020. CC BY 4.0 License. Ribbed bedforms in palaeo-ice streams reveal shear margin positions, lobe shutdown and the interaction of meltwater drainage and ice velocity patterns Jean Vérité1, Édouard Ravier1, Olivier Bourgeois2, Stéphane Pochat2, Thomas Lelandais1, Régis 5 Mourgues1, Christopher D. Clark3, Paul Bessin1, David Peigné1, Nigel Atkinson4 1 Laboratoire de Planétologie et Géodynamique, UMR 6112, CNRS, Le Mans Université, Avenue Olivier Messiaen, 72085 Le Mans CEDEX 9, France 2 Laboratoire de Planétologie et Géodynamique, UMR 6112, CNRS, Université de Nantes, 2 rue de la Houssinière, BP 92208, 44322 Nantes CEDEX 3, France 10 3 Department of Geography, University of Sheffield, Sheffield, UK 4 Alberta Geological Survey, 4th Floor Twin Atria Building, 4999-98 Ave. Edmonton, AB, T6B 2X3, Canada Correspondence to: Jean Vérité ([email protected]) Abstract. Conceptual ice stream landsystems derived from geomorphological and sedimentological observations provide 15 constraints on ice-meltwater-till-bedrock interactions on palaeo-ice stream beds. Within these landsystems, the spatial distribution and formation processes of ribbed bedforms remain unclear. We explore the conditions under which these bedforms develop and their spatial organisation with (i) an experimental model that reproduces the dynamics of ice streams and subglacial landsystems and (ii) an analysis of the distribution of ribbed bedforms on selected examples of paleo-ice stream beds of the Laurentide Ice Sheet. We find that a specific kind of ribbed bedforms can develop subglacially 20 from a flat bed beneath shear margins (i.e., lateral ribbed bedforms) and lobes (i.e., submarginal ribbed bedforms) of ice streams. -
A Review of Ice-Sheet Dynamics in the Pine Island Glacier Basin, West Antarctica: Hypotheses of Instability Vs
Pine Island Glacier Review 5 July 1999 N:\PIGars-13.wp6 A review of ice-sheet dynamics in the Pine Island Glacier basin, West Antarctica: hypotheses of instability vs. observations of change. David G. Vaughan, Hugh F. J. Corr, Andrew M. Smith, Adrian Jenkins British Antarctic Survey, Natural Environment Research Council Charles R. Bentley, Mark D. Stenoien University of Wisconsin Stanley S. Jacobs Lamont-Doherty Earth Observatory of Columbia University Thomas B. Kellogg University of Maine Eric Rignot Jet Propulsion Laboratories, National Aeronautical and Space Administration Baerbel K. Lucchitta U.S. Geological Survey 1 Pine Island Glacier Review 5 July 1999 N:\PIGars-13.wp6 Abstract The Pine Island Glacier ice-drainage basin has often been cited as the part of the West Antarctic ice sheet most prone to substantial retreat on human time-scales. Here we review the literature and present new analyses showing that this ice-drainage basin is glaciologically unusual, in particular; due to high precipitation rates near the coast Pine Island Glacier basin has the second highest balance flux of any extant ice stream or glacier; tributary ice streams flow at intermediate velocities through the interior of the basin and have no clear onset regions; the tributaries coalesce to form Pine Island Glacier which has characteristics of outlet glaciers (e.g. high driving stress) and of ice streams (e.g. shear margins bordering slow-moving ice); the glacier flows across a complex grounding zone into an ice shelf coming into contact with warm Circumpolar Deep Water which fuels the highest basal melt-rates yet measured beneath an ice shelf; the ice front position may have retreated within the past few millennia but during the last few decades it appears to have shifted around a mean position. -
A New Bed Elevation Model for the Weddell Sea Sector of the West Antarctic Ice Sheet
Earth Syst. Sci. Data, 10, 711–725, 2018 https://doi.org/10.5194/essd-10-711-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. A new bed elevation model for the Weddell Sea sector of the West Antarctic Ice Sheet Hafeez Jeofry1,2, Neil Ross3, Hugh F. J. Corr4, Jilu Li5, Mathieu Morlighem6, Prasad Gogineni7, and Martin J. Siegert1 1Grantham Institute and Department of Earth Science and Engineering, Imperial College London, South Kensington, London, UK 2School of Marine Science and Environment, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia 3School of Geography, Politics and Sociology, Newcastle University, Claremont Road, Newcastle Upon Tyne, UK 4British Antarctic Survey, Natural Environment Research Council, Cambridge, UK 5Center for the Remote Sensing of Ice Sheets, University of Kansas, Lawrence, Kansas, USA 6Department of Earth System Science, University of California, Irvine, Irvine, California, USA 7Department of Electrical and Computer Engineering, The University of Alabama, Tuscaloosa, Alabama 35487, USA Correspondence: Hafeez Jeofry ([email protected]) and Martin J. Siegert ([email protected]) Received: 11 August 2017 – Discussion started: 26 October 2017 Revised: 26 October 2017 – Accepted: 5 February 2018 – Published: 9 April 2018 Abstract. We present a new digital elevation model (DEM) of the bed, with a 1 km gridding, of the Weddell Sea (WS) sector of the West Antarctic Ice Sheet (WAIS). The DEM has a total area of ∼ 125 000 km2 covering the Institute, Möller and Foundation ice streams, as well as the Bungenstock ice rise. In comparison with the Bedmap2 product, our DEM includes new aerogeophysical datasets acquired by the Center for Remote Sensing of Ice Sheets (CReSIS) through the NASA Operation IceBridge (OIB) program in 2012, 2014 and 2016. -
Ilulissat Icefjord
World Heritage Scanned Nomination File Name: 1149.pdf UNESCO Region: EUROPE AND NORTH AMERICA __________________________________________________________________________________________________ SITE NAME: Ilulissat Icefjord DATE OF INSCRIPTION: 7th July 2004 STATE PARTY: DENMARK CRITERIA: N (i) (iii) DECISION OF THE WORLD HERITAGE COMMITTEE: Excerpt from the Report of the 28th Session of the World Heritage Committee Criterion (i): The Ilulissat Icefjord is an outstanding example of a stage in the Earth’s history: the last ice age of the Quaternary Period. The ice-stream is one of the fastest (19m per day) and most active in the world. Its annual calving of over 35 cu. km of ice accounts for 10% of the production of all Greenland calf ice, more than any other glacier outside Antarctica. The glacier has been the object of scientific attention for 250 years and, along with its relative ease of accessibility, has significantly added to the understanding of ice-cap glaciology, climate change and related geomorphic processes. Criterion (iii): The combination of a huge ice sheet and a fast moving glacial ice-stream calving into a fjord covered by icebergs is a phenomenon only seen in Greenland and Antarctica. Ilulissat offers both scientists and visitors easy access for close view of the calving glacier front as it cascades down from the ice sheet and into the ice-choked fjord. The wild and highly scenic combination of rock, ice and sea, along with the dramatic sounds produced by the moving ice, combine to present a memorable natural spectacle. BRIEF DESCRIPTIONS Located on the west coast of Greenland, 250-km north of the Arctic Circle, Greenland’s Ilulissat Icefjord (40,240-ha) is the sea mouth of Sermeq Kujalleq, one of the few glaciers through which the Greenland ice cap reaches the sea. -
Ice-Flow Structure and Ice Dynamic Changes in the Weddell Sea Sector
Bingham RG, Rippin DM, Karlsson NB, Corr HFJ, Ferraccioli F, Jordan TA, Le Brocq AM, Rose KC, Ross N, Siegert MJ. Ice-flow structure and ice-dynamic changes in the Weddell Sea sector of West Antarctica from radar-imaged internal layering. Journal of Geophysical Research: Earth Surface 2015, 120(4), 655-670. Copyright: ©2015 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. DOI link to article: http://dx.doi.org/10.1002/2014JF003291 Date deposited: 04/06/2015 This work is licensed under a Creative Commons Attribution 4.0 International License Newcastle University ePrints - eprint.ncl.ac.uk PUBLICATIONS Journal of Geophysical Research: Earth Surface RESEARCH ARTICLE Ice-flow structure and ice dynamic changes 10.1002/2014JF003291 in the Weddell Sea sector of West Antarctica Key Points: from radar-imaged internal layering • RES-sounded internal layers in Institute/Möller Ice Streams show Robert G. Bingham1, David M. Rippin2, Nanna B. Karlsson3, Hugh F. J. Corr4, Fausto Ferraccioli4, fl ow changes 4 5 6 7 8 • Ice-flow reconfiguration evinced in Tom A. Jordan , Anne M. Le Brocq , Kathryn C. Rose , Neil Ross , and Martin J. Siegert Bungenstock Ice Rise to higher 1 2 tributaries School of GeoSciences, University of Edinburgh, Edinburgh, UK, Environment Department, University of York, York, UK, • Holocene dynamic reconfiguration 3Centre for Ice and Climate, Niels Bohr Institute, University -
Glacial Processes and Landforms-Transport and Deposition
Glacial Processes and Landforms—Transport and Deposition☆ John Menziesa and Martin Rossb, aDepartment of Earth Sciences, Brock University, St. Catharines, ON, Canada; bDepartment of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON, Canada © 2020 Elsevier Inc. All rights reserved. 1 Introduction 2 2 Towards deposition—Sediment transport 4 3 Sediment deposition 5 3.1 Landforms/bedforms directly attributable to active/passive ice activity 6 3.1.1 Drumlins 6 3.1.2 Flutes moraines and mega scale glacial lineations (MSGLs) 8 3.1.3 Ribbed (Rogen) moraines 10 3.1.4 Marginal moraines 11 3.2 Landforms/bedforms indirectly attributable to active/passive ice activity 12 3.2.1 Esker systems and meltwater corridors 12 3.2.2 Kames and kame terraces 15 3.2.3 Outwash fans and deltas 15 3.2.4 Till deltas/tongues and grounding lines 15 Future perspectives 16 References 16 Glossary De Geer moraine Named after Swedish geologist G.J. De Geer (1858–1943), these moraines are low amplitude ridges that developed subaqueously by a combination of sediment deposition and squeezing and pushing of sediment along the grounding-line of a water-terminating ice margin. They typically occur as a series of closely-spaced ridges presumably recording annual retreat-push cycles under limited sediment supply. Equifinality A term used to convey the fact that many landforms or bedforms, although of different origins and with differing sediment contents, may end up looking remarkably similar in the final form. Equilibrium line It is the altitude on an ice mass that marks the point below which all previous year’s snow has melted. -
The Ministry for the Future / Kim Stanley Robinson
This book is a work of fiction. Names, characters, places, and incidents are the product of the author’s imagination or are used fictitiously. Any resemblance to actual events, locales, or persons, living or dead, is coincidental. Copyright © 2020 Kim Stanley Robinson Cover design by Lauren Panepinto Cover images by Trevillion and Shutterstock Cover copyright © 2020 by Hachette Book Group, Inc. Hachette Book Group supports the right to free expression and the value of copyright. The purpose of copyright is to encourage writers and artists to produce the creative works that enrich our culture. The scanning, uploading, and distribution of this book without permission is a theft of the author’s intellectual property. If you would like permission to use material from the book (other than for review purposes), please contact [email protected]. Thank you for your support of the author’s rights. Orbit Hachette Book Group 1290 Avenue of the Americas New York, NY 10104 www.orbitbooks.net First Edition: October 2020 Simultaneously published in Great Britain by Orbit Orbit is an imprint of Hachette Book Group. The Orbit name and logo are trademarks of Little, Brown Book Group Limited. The publisher is not responsible for websites (or their content) that are not owned by the publisher. The Hachette Speakers Bureau provides a wide range of authors for speaking events. To find out more, go to www.hachettespeakersbureau.com or call (866) 376-6591. Library of Congress Cataloging-in-Publication Data Names: Robinson, Kim Stanley, author. Title: The ministry for the future / Kim Stanley Robinson. Description: First edition. -
This Article Appeared in a Journal Published by Elsevier. the Attached
This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier’s archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Author's personal copy Palaeogeography, Palaeoclimatology, Palaeoecology 299 (2011) 363–384 Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo The Mendel Formation: Evidence for Late Miocene climatic cyclicity at the northern tip of the Antarctic Peninsula Daniel Nývlt a,⁎, Jan Košler b,c, Bedřich Mlčoch b, Petr Mixa b, Lenka Lisá d, Miroslav Bubík a, Bart W.H. Hendriks e a Czech Geological Survey, Brno branch, Leitnerova 22, 658 69 Brno, Czechia b Czech Geological Survey, Klárov 3, 118 21 Praha 1, Czechia c Department of Earth Science, University of Bergen, Allegaten 41, Bergen, Norway d Institute of Geology of the Czech Academy of Sciences, v.v.i., Rozvojová 269, 165 02 Praha, Czechia e Geological Survey of Norway, Leiv Eirikssons vei 39, 7491 Trondheim, Norway article info abstract Article history: A detailed description of the newly defined Mendel Formation is presented. This Late Miocene (5.9–5.4 Ma) Received 31 May 2010 sedimentary sequence with an overall thickness of more than 80 m comprises cyclic deposition in terrestrial Received in revised form 9 November 2010 glacigenic, glaciomarine and marine environments. -
Davis Valley and Forlidas Pond, Dufek Massif
Measure 2 (2005) Annex D Management Plan for Antarctic Specially Protected Area No. 119 DAVIS VALLEY AND FORLIDAS POND, DUFEK MASSIF 1. Description of Values to be Protected Forlidas Pond (82°27'28"S, 51°16'48"W) and several ponds along the northern ice margin of the Davis Valley (82°27'30"S, 51°05'W), in the Dufek Massif, Pensacola Mountains, were originally designated as a Specially Protected Area through Recommendation XVI-9 (1991, SPA No. 23) after a proposal by the United States of America. The Area was designated on the grounds that it “contains some of the most southerly freshwater ponds known in Antarctica containing plant life” which “should be protected as examples of unique near-pristine freshwater ecosystems and their catchments”. The original Area comprised two sections approximately 500 metres apart with a combined total area of around 6 km2. It included Forlidas Pond and the meltwater ponds along the ice margin at the northern limit of the Davis Valley. The site has been rarely visited and until recently there has been little information available on the ecosystems within the Area. This Management Plan reaffirms the original reason for designation of the Area, recognizing the ponds and their associated plant life as pristine examples of a southerly freshwater habitat. However, following a field visit made in December 2003 (Hodgson and Convey, 2004) the values identified for special protection and the boundaries for the Area have been expanded as described below. The Davis Valley and the adjacent ice-free valleys is one of the most southerly ‘dry valley’ systems in Antarctica and, as of May 2005, is the most southerly protected area in Antarctica. -
Here Westerlies in Patagonia and South Georgia Island; Kreutz K (PI), Campbell S (Co-PI) $11,952
Seth William Campbell University of Maine Juneau Icefield Research Program Climate Change Institute The Foundation for Glacier School of Earth & Climate Sciences & Environmental Research 202 Sawyer Hall 4616 25th Avenue NE, Suite 302 Orono, Maine 04469-5790 Seattle, Washington 98105 [email protected] [email protected] 207-581-3927 www.alpinesciences.net Education 2014 Ph.D. Earth & Climate Sciences University of Maine, Orono 2010 M.S. Earth Sciences University of Maine, Orono 2008 B.S. Earth Sciences University of Maine, Orono 2005 M. Business Administration University of Maine, Orono 2001 B.A. Environmental Science, Minor: Geology University of Maine, Farmington Current Employment 2018 – Present University of Maine, Assistant Professor of Glaciology; Climate Change Institute and School of Earth & Climate Sciences 2018 – Present Juneau Icefield Research Program, Director of Academics & Research 2016 – Present ERDC-CRREL, Research Geophysicist (Intermittent Status) Prior Employment 2015 – 2018 University of Maine, Research Assistant Professor 2016 – 2018 University of Washington, Post-Doctoral Research Associate 2014 – 2016 ERDC-CRREL, Research Geophysicist 2014 – 2017 University of California, Davis, Research Associate 2011 – 2014 University of Maine, Graduate Research Assistant 2009 – 2014 ERDC-CRREL, Research Physical Scientist 2010 – 2012 University of Washington, Professional Research Staff 2008 – 2009 University of Maine, Graduate Teaching Assistant 2000 E/Pro Engineering & Environmental Consulting, Survey Technician 1999 -
Glaciers of the Canadian Rockies
Glaciers of North America— GLACIERS OF CANADA GLACIERS OF THE CANADIAN ROCKIES By C. SIMON L. OMMANNEY SATELLITE IMAGE ATLAS OF GLACIERS OF THE WORLD Edited by RICHARD S. WILLIAMS, Jr., and JANE G. FERRIGNO U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1386–J–1 The Rocky Mountains of Canada include four distinct ranges from the U.S. border to northern British Columbia: Border, Continental, Hart, and Muskwa Ranges. They cover about 170,000 km2, are about 150 km wide, and have an estimated glacierized area of 38,613 km2. Mount Robson, at 3,954 m, is the highest peak. Glaciers range in size from ice fields, with major outlet glaciers, to glacierets. Small mountain-type glaciers in cirques, niches, and ice aprons are scattered throughout the ranges. Ice-cored moraines and rock glaciers are also common CONTENTS Page Abstract ---------------------------------------------------------------------------- J199 Introduction----------------------------------------------------------------------- 199 FIGURE 1. Mountain ranges of the southern Rocky Mountains------------ 201 2. Mountain ranges of the northern Rocky Mountains ------------ 202 3. Oblique aerial photograph of Mount Assiniboine, Banff National Park, Rocky Mountains----------------------------- 203 4. Sketch map showing glaciers of the Canadian Rocky Mountains -------------------------------------------- 204 5. Photograph of the Victoria Glacier, Rocky Mountains, Alberta, in August 1973 -------------------------------------- 209 TABLE 1. Named glaciers of the Rocky Mountains cited in the chapter