Michelle Rebecca Koutnik

Total Page:16

File Type:pdf, Size:1020Kb

Michelle Rebecca Koutnik Michelle Rebecca Koutnik Department of Earth and Space Sciences University of Washington, Box 351310, Seattle, WA 98195 (206) 221-5041 [email protected] ________________________________________________________________________ EDUCATION Ph.D. in Geophysics Nov 2009 University of Washington, Seattle Ph.D. thesis: Inferring histories of accumulation rate, ice thickness, and ice flow from internal layers in glaciers and ice sheets B.S. in Astrophysics, minor in Geophysics/Planetary Science June 2001 University of California, Los Angeles RESEARCH EXPERIENCE Research assistant professor July 2013 – present University of Washington Research associate Oct 2012 – June 2013 University of Washington Postdoctoral Research Fellow Feb 2010 – Sept 2012 University of Copenhagen, Host: Dorthe Dahl-Jensen Graduate Research Assistant Sept 2002 – Nov 2009 University of Washington, Advisor: Ed Waddington International Research Exchange Aug - Oct 2007 Centre for Ice and Climate, Copenhagen, Denmark Funded by the Center for Remote Sensing of Ice Sheets, Univ. of Kansas Fulbright Fellow Sept 2001-Aug 2002 University of Calgary, Canada, Advisor: Shawn Marshall Visiting appointment in Planetary Science 2001-2008 Caltech Undergraduate Research Assistant June 2000 – Sept 2001 Caltech, Advisor: Bruce Murray Undergraduate Research Assistant June 1999 – Dec 2000 Mars Polar Lander, UCLA, assisted the Mars Microphone and Light Detection and Ranging (LIDAR) teams, Advisor: David Paige 1 Research interests: Glacier and ice-sheet dynamics; ice masses on Mars; interpretation of radar data; ice-flow modeling and geophysical inverse methods to understand ice and climate histories FIELD EXPERIENCE Beardmore Glacier, Antarctica Oct – Dec 2012 Part of a five-person field team (including Howard Conway and Paul Winberry); Collected ground and airborne radar data and conducted active and passive seismic experiments Central West Antarctica Nov – Dec 2011 Led five-person field team on 500 km snow machine traverse, similar to 2010 campaign Greenland, NEEM ice-core site May – June 2011 Assisted with core processing of deep ice; assisted drilling a new 400-meter ice core at the North Greenland Eemian (NEEM) camp Central West Antarctica Nov – Dec 2010 Assisted Lora Koenig (NASA) and Summer Rupper (Brigham Young University); Drilled shallow ice cores and collected radar data on a traverse across West Antarctic Divide Zermatt, Switzerland May 2010 Assisted Summer Rupper (Brigham Young University); Collected radar data, survey, drilled shallow ice cores on Zwillings Glacier Blue Glacier, Olympic Mountains, Washington summer trips in 2002-2008 Collaborated with Howard Conway and Al Rasmussen; Collected and processed GPS data, installed and maintained temperature sensors and snow-depth sensor llulissat, West Greenland October 2007 Assisted Ginny Catania (Univ. of Texas, Austin); Retrieved GPS units Dry Valleys, Antarctica Nov 2004 – Feb 2005 Assisted Erin Pettit (Univ. of Alaska, Fairbanks); Installed six seismometers, assisted with wiring, calibration, and installation of tilt sensors and temperature sensors, assisted with collection and processing of shallow ice cores Haig Glacier, Canada winter trip 2001, spring and summer trips 2002 Assisted Shawn Marshall (Univ. of Calgary); Mass-balance measurements, snow-pit analysis, and weather-station installation and maintenance TEACHING EXPERIENCE Instructor, Workshop on Applications of Radar Data 12-16 March 2012 SVALI course hosted by Centre for Ice and Climate, Copenhagen Co-instructor, Exploration Seminar to Greenland 12 Aug - 2 Sept 2008 University of Washington, Department of Earth and Space Sciences Co-instructed with Gerard Roe; developed new study-abroad undergraduate course with a focus on ice, climate, and culture of Greenland, and travel to Greenland 2 Teaching Assistant, Introductory Seismology Winter 2002 and 2003 University of Washington, Department of Earth and Space Sciences Teaching Assistant, Introductory Space Physics Fall 2002 and 2003 University of Washington, Department of Earth and Space Sciences Teaching Assistant, Introductory Geology Fall 2002 University of Washington, Department of Earth and Space Sciences AWARDS National Science Foundation International Research Fellowship 2009 Two-year postdoctoral position at Centre for Ice and Climate, Univ. of Copenhagen, Denmark Johnston Award for Research 2006 University of Washington, Earth and Space Sciences Graduate research award 2004-2007 University of Washington, Earth and Space Sciences National Science Foundation Graduate Research Fellowship 2004 Three-year graduate fellowship at University of Washington Evolving Earth Foundation Graduate Research Grant 2003 David Bonderman International Travel Fellowship 2003 University of Washington; four months explorative travel to Canada, Iceland, and Greenland Fulbright Fellowship, United States-Canada 2001 Caltech Summer Undergraduate Research Award 2000 INVITED LECTURES Inferring histories of accumulation, ice thickness and ice-divide position Oct 2010 British Antarctic Survey, Cambridge Inferring histories of accumulation rate, ice thickness, and ice flow May 2010 from ice-sheet internal layers Centre for Ice and Climate, University of Copenhagen Using ice-surface topography and internal layers Feb 2010 to infer past ice-flow rates and past mass balance on Mars University of Texas Institute for Geophysics, Austin Fifty years at Blue Glacier and South Cascade Glacier 24 May 2007 with Al Rasmussen, University of Washington Climate Impacts Group 3 Blue Glacier and its response to climate change 14 March 2006 with Howard Conway, Olympic National Park lecture series ACTIVITIES Lectures to undergraduate students May 2011 and Aug 2012 Introduction to ice-sheet modeling Summer-course participant 8-19 June 2010 Advanced Climate Dynamics Course, Norway, topic: Marine/Ice Sheet Interactions Invited participant October 2008 International Space Science Institute (Bern, Switzerland) funded workshop on Mars Polar Ice and Climate Referee Since 2005 Geophysical Research Letters, Icarus, Journal of Geophysical Research, Journal of Glaciology, Mars Journal, Quaternary Research Summer-course participant 15-26 June 2003 Grand Combin Summer School, Italy, topic: Paleoclimate Observations and Modelling PUBLICATIONS 1. Winebrenner, D.P., A.V. Pathare, E.D. Waddington, M.R. Koutnik. Stratigraphy and topography on Gemina Lingula reveal a history of episodic ice flow. In preparation. 2. NEEM Community Members (including M.R. Koutnik). 2013. Eemian interglacial reconstructed from a Greenland folded NEEM ice core strata. Nature 493, 489-494. 3. Burgener, L., S. Rupper, L. Koenig, R. Forster, W. Christensen, J. Williams, M.R. Koutnik, C. Miége, E. Steig. 2013. An observed negative trend in West Antarctic accumulation rates from 1975 to 2010: evidence from new observed and simulated records. Submitted to Journal of Geophysical Research 118, doi:10.1002/jgrd.50362. 4. Koutnik, M.R., E.D. Waddington, D.P. Winebrenner, and A.V. Pathare. 2013. Response timescales for Martian ice masses and implications for ice flow on Mars. Icarus 225, 949-959. 5. McBride, J., S. Rupper, S. Ritter, D. Tingey, M.R. Koutnik, A Quick, T. Morris, R. Keach, II, L. Burgener, A. McKean, J. Williams, J. Maurer, D. Keeler, R. Windell. 2012. Relationship between wave ogives and radar scattering in an alpine glacier. Geosphere 8 (5), 1054-1077. 4 6. Koutnik, M.R. and E.D. Waddington. 2012. Well-posed boundary conditions for limited-domain models of transient ice flow near an ice divide. Journal of Glaciology 58 (211), 1008-1020. 7. Steen-Larsen, H.C., E.D. Waddington, and M.R. Koutnik. 2010. Formulating an inverse problem to infer the accumulation-rate pattern from deep internal layering in an ice sheet using a Monte-Carlo Approach. Journal of Glaciology 56 (196), 318-332. 8. Koutnik, M.R., E.D. Waddington, and D.P. Winebrenner. 2009. A method to infer past surface mass balance and topography from internal layers in Martian Polar Layered Deposits. Icarus 204, 458-470. 9. MacGregor, J.A., K. Matsuoka, M.R. Koutnik, E.D. Waddington, M. Studinger, and D.P. Winebrenner. 2009. Mapping millennially averaged accumulation rates for the Lake Vostok region using deep internal layers and inverse methods. Annals of Glaciology 50 (51), 25-34. 10. Fishbaugh, K.E., C.S. Hvidberg, D. Beaty, S. Clifford, A. Haldermann, J.W. Head, M. Hecht, M.R. Koutnik, and K. Tanaka. 2008. Introduction to the 4th Mars Polar Science and Exploration Conference Special Issue: Five top questions in Mars Polar Science. Icarus 196, 305-317. 11. Winebrenner, D.P., M.R. Koutnik, E.D. Waddington, A.V. Pathare, B.C. Murray, S. Byrne, J.L. Bamber. 2007. Evidence for ice flow prior to trough formation in the Martian North Polar Layered Deposits. Icarus 195, 90-105. 12. Waddington, E.D., T.A. Neumann, M.R. Koutnik, H.P. Marshall, D.L. Morse. 2007. Inference of accumulation-rate patterns from deep internal layers. Journal of Glaciology 53, 694-712. 13. Marshall, S. and M.R. Koutnik. 2006. Ice sheet action versus reaction: Distinguishing between Heinrich events and Dansgaard-Oeschger cycles in the North Atlantic. Paleoceanography 21, doi:10.1029/2005PA001247. 14. Koutnik, M.R., S. Byrne, B. Murray, A. Toigo, and Z. Crawford, 2005. Eolian controlled modification of the martian south polar layered deposits. Icarus 174, 490-501. 15. Koutnik, M.R., S. Byrne, and B. Murray, 2002. The South Polar Layered Deposits of Mars: The Cratering Record. Journal of Geophysical Research, 107 (E11), 5100-5112. 16. Murray, B., M.R. Koutnik,
Recommended publications
  • Reframing an Arctic Image, out of the Sublime
    University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2016-01-26 Reframing an Arctic Image, Out of the Sublime Thoreson, Kristine, Nicole Thoreson, K. (2016). Reframing an Arctic Image, Out of the Sublime (Unpublished doctoral thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/27572 http://hdl.handle.net/11023/2779 doctoral thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Reframing an Arctic Image, Out of the Sublime by Kristine Thoreson A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY GRADUATE PROGRAM OF ART CALGARY, ALBERTA January, 2016 © Kristine Thoreson 2016 Abstract A proliferation of sublime, mythic and nearly vacant landscape photographs of Arctic regions are circulating in museums and galleries internationally; artist monographs of these photographs are also readily available in major booksellers. Although the photographs are artfully crafted and technically superior, there is the question of what an accretion of so many sublime landscape images of the North accomplishes in terms of perceptions of place, community and culture? It is true that creating awe-inspiring photographs that promote an appreciation for polar-regions is legitimate work.
    [Show full text]
  • Perennial Ice and Snow Masses
    " :1 i :í{' ;, fÎ :~ A contribution to the International Hydrological' Decade Perennial ice and snow masses A guide for , compilation and assemblage of data for a world inventory unesco/iash " ' " I In this series: '1 Perennial Ice and Snow Masses. A Guide for Compilation and Assemblage of Data for a World Inventory. 2 Seasonal Snow Cower. A Guide for Measurement, Compilation and Assemblage of Data. 3 Variations of Existing Glaciers. A Guide to International Practices for their Measurement.. 4 Antartie Glaciology in the International Hydrological Decade. S Combined Heat, Ice and Water Balances at Selected Glacier Basins. A Guide for Compilation and Assemblage of Data for Glacier Mass Balance ( Measurements. (- ~------------------ ", _.::._-~,.:- r- ,.; •.'.:-._ ': " :;-:"""':;-iij .if( :-:.:" The selection and presentation of material and the opinions expressed in this publication are the responsibility of the authors concerned 'and do not necessarily reflect , , the views of Unesco. Nor do the designations employed or the presentation of the material imply the expression of any opinion whatsoever on the part of Unesco concerning the legal status of any country or territory, or of its authorities, or concerning the frontiers of any country or territory. Published in 1970 by the United Nations Bducational, Scientific and Cultal al OrganIzatIon, Place de Fontenoy, 75 París-r-. Printed by Imprimerie-Reliure Marne. © Unesco/lASH 1970 Printed in France SC.6~/XX.1/A. ...•.•• :. ;'::'~~"::::'??<;~;~8~~~ (,: :;H,.,Wfuif:: Preface The International Hydrological Decade _(IHD) As part of Unesco's contribution to the achieve- 1965-1974was launched hy the General Conference ment of the objectives of, the IHD the General of Unesco at its thirteenth session to promote Conference authorized the Director-General to international co-operation in research and studies collect, exchange and disseminate information and the training of specialists and technicians in concerning research on scientific hydrology and to scientific hydrology.
    [Show full text]
  • Perennial Ice and Snow Masses
    Technical papers in hydrology 1 In this series: 1 Perennial Ice and Snow Masses. A Guide for Compilation and Assemblage of Data for a World Inventory. 2 Seasonal Snow Cower. A Guide for Measurement, Compilation and Assemblage of Data. 3 Variations of Existing Glaciers. A Guide to International Practices for their Measurement. 4 Antartic Glaciology in the International Hydrological Decade. 5 Combined Heat, Ice and Water Balances at Selected Glacier Basins. A Guide for Compilation and Assemblage of Data for Glacier Mass Balance Measurements. A contribution to the International Hydrological Decade Perennial ice and snow masses A guide for compilation and assemblage of data for a world inventory nesco/iash The selection and presentation of material and the opinions expressed in this publication are the responsibility of the authors concerned and do not necessarily reflect the views of Unesco. Nor do the designations employed or the presentation of the material imply the expression of any opinion whatsoever on the part of Unesco concerning the legal status of any country or territory, or of its authorities, or concerning the frontiers of any country or territory. Published in 1970 by the United Nations Educational, Scientific and Cultural Organization, Place de Fontenoy, 75 Paris-7C. Printed by Imprimerie-Reliure Mame. © Unesco/I ASH 1970 Printed in France SC.68/XX.1/A. Preface The International Hydrological Decade (IHD) As part of Unesco's contribution to the achieve­ 1965-1974 was launched by the General Conference ment of the objectives of the IHD the General of Unesco at its thirteenth session to promote Conference authorized the Director-General to international co-operation in research and studies collect, exchange and disseminate information and the training of specialists and technicians in concerning research on scientific hydrology and to scientific hydrology.
    [Show full text]
  • Hydrologic and Mass-Movement Hazards Near Mccarthy Wrangell-St
    Hydrologic and Mass-Movement Hazards near McCarthy Wrangell-St. Elias National Park and Preserve, Alaska By Stanley H. Jones and Roy L Glass U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 93-4078 Prepared in cooperation with the NATIONAL PARK SERVICE Anchorage, Alaska 1993 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY ROBERT M. HIRSCH, Acting Director For additional information write to: Copies of this report may be purchased from: District Chief U.S. Geological Survey U.S. Geological Survey Earth Science Information Center 4230 University Drive, Suite 201 Open-File Reports Section Anchorage, Alaska 99508-4664 Box 25286, MS 517 Denver Federal Center Denver, Colorado 80225 CONTENTS Abstract ................................................................ 1 Introduction.............................................................. 1 Purpose and scope..................................................... 2 Acknowledgments..................................................... 2 Hydrology and climate...................................................... 3 Geology and geologic hazards................................................ 5 Bedrock............................................................. 5 Unconsolidated materials ............................................... 7 Alluvial and glacial deposits......................................... 7 Moraines........................................................ 7 Landslides....................................................... 7 Talus..........................................................
    [Show full text]
  • The Dynamics and Mass Budget of Aretic Glaciers
    DA NM ARKS OG GRØN L ANDS GEO L OG I SKE UNDERSØGELSE RAP P ORT 2013/3 The Dynamics and Mass Budget of Aretic Glaciers Abstracts, IASC Network of Aretic Glaciology, 9 - 12 January 2012, Zieleniec (Poland) A. P. Ahlstrøm, C. Tijm-Reijmer & M. Sharp (eds) • GEOLOGICAL SURVEY OF D EN MARK AND GREENLAND DANISH MINISTAV OF CLIMATE, ENEAGY AND BUILDING ~ G E U S DANMARKS OG GRØNLANDS GEOLOGISKE UNDERSØGELSE RAPPORT 201 3 / 3 The Dynamics and Mass Budget of Arctic Glaciers Abstracts, IASC Network of Arctic Glaciology, 9 - 12 January 2012, Zieleniec (Poland) A. P. Ahlstrøm, C. Tijm-Reijmer & M. Sharp (eds) GEOLOGICAL SURVEY OF DENMARK AND GREENLAND DANISH MINISTRY OF CLIMATE, ENERGY AND BUILDING Indhold Preface 5 Programme 6 List of participants 11 Minutes from a special session on tidewater glaciers research in the Arctic 14 Abstracts 17 Seasonal and multi-year fluctuations of tidewater glaciers cliffson Southern Spitsbergen 18 Recent changes in elevation across the Devon Ice Cap, Canada 19 Estimation of iceberg to the Hansbukta (Southern Spitsbergen) based on time-lapse photos 20 Seasonal and interannual velocity variations of two outlet glaciers of Austfonna, Svalbard, inferred by continuous GPS measurements 21 Discharge from the Werenskiold Glacier catchment based upon measurements and surface ablation in summer 2011 22 The mass balance of Austfonna Ice Cap, 2004-2010 23 Overview on radon measurements in glacier meltwater 24 Permafrost distribution in coastal zone in Hornsund (Southern Spitsbergen) 25 Glacial environment of De Long Archipelago
    [Show full text]
  • West Antarctic Ice Sheet Divide Ice Core Climate, Ice Sheet History, Cryobiology
    WAIS DIVIDE SCIENCE COORDINATION OFFICE West Antarctic Ice Sheet Divide Ice Core Climate, Ice Sheet History, Cryobiology A GUIDE FOR THE MEDIA AND PUBLIC Field Season 2011-2012 WAIS (West Antarctic Ice Sheet) Divide is a United States deep ice coring project in West Antarctica funded by the National Science Foundation (NSF). WAIS Divide’s goal is to examine the last ~100,000 years of Earth’s climate history by drilling and recovering a deep ice core from the ice divide in central West Antarctica. Ice core science has dramatically advanced our understanding of how the Earth’s climate has changed in the past. Ice cores collected from Greenland have revolutionized our notion of climate variability during the past 100,000 years. The WAIS Divide ice core will provide the first Southern Hemisphere climate and greenhouse gas records of comparable time resolution and duration to the Greenland ice cores enabling detailed comparison of environmental conditions between the northern and southern hemispheres, and the study of greenhouse gas concentrations in the paleo-atmosphere, with a greater level of detail than previously possible. The WAIS Divide ice core will also be used to test models of WAIS history and stability, and to investigate the biological signals contained in deep Antarctic ice cores. 1 Additional copies of this document are available from the project website at http://www.waisdivide.unh.edu Produced by the WAIS Divide Science Coordination Office with support from the National Science Foundation, Office of Polar Programs. 2 Contents
    [Show full text]
  • Glaciation in Alaska
    SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1931 GLACIATION IN ALASKA By STEPHEN R. CAPPS INTRODUCTION examination. Interior Alaska, on tke other The history of glaciation in Alaska offers a fas­ presents a great driftless area, in the basins o* the cinating field for study. Because of the remarkable Yukon, Tanana, and Kuskokwim Rivers, where low development and easy accessibility of valley and pied­ relief and dry climate prohibited the formation of mont glaciers in the coastal mountains, Alaska has glaciers. This unglaciated region was encrorehed long been popularly conceived as a land of ice and snow, upon by the continental ice sheets from the eas* and a concept that is only slowly being corrected. To by mountain glaciers from the north and s^utfe. the student of glaciation, however, Alaska affords a Along its margins at several localities there have unique opportunity to observe the formation, move­ already been found evidences of glacial advances ment, and dissipation of the many living glaciers, to preceding the last great glaciation, and it seems ee^ain examine the results of glacial erosion on a gigantic that future studies will bring additional observa tieas scale, and to discover and work out the sequence of that will shed much light on the glacial history cf the Pleistocene events as shown by the topographic forms continent. in both glaciated and unglaciated areas and by the * There is an extensive literature on glaciation in deposits left by ice and water during earlier stages of Alaska, yet in view of the great area of the Terrf.tory, glaciation. the number and size of its living glaciers, and the The evidence for successive glacial advances in extensive area covered by ice during Pleistocene time, many parts of the world during Pleistocene time has it must be confessed that little more than a beginning been largely obtained in regions not far from the outer has been made toward an adequate understanding of margin reached by the glaciers during the different its glacial history.
    [Show full text]
  • Rapid Ice Sheet Retreat Triggered by Ice Stream Debuttressing: Evidence from the North Sea
    Rapid ice sheet retreat triggered by ice stream debuttressing: Evidence from the North Sea Hans Petter Sejrup1, Chris D. Clark2, and Berit O. Hjelstuen1 1Department of Earth Science, University of Bergen, Allegaten 41, 5007 Bergen, Norway 2Department of Geography, University of Sheffield, Sheffield S10 2TN, UK ABSTRACT DATA AND METHODS Using high-resolution bathymetric and shallow seismic data from the North Sea, we have Seabed imagery and bathymetric informa- mapped hitherto unknown glacial landforms that connect and resolve longstanding gaps in tion were obtained from the Olex database (Olex the Quaternary geological history of the basin. We use these data combined with published AS, www.olex.no), representing the seafloor as information and dates from sediment cores to reconstruct the extent of the Fennoscandian a series of 5 × 5 m cells with a vertical accu- and British Ice Sheets (FIS and BIS) in the North Sea during the last phases of the last glacial racy of <1 m (Fig. 1A). Approximately 12,800 stage. It is concluded that the BIS occupied a much larger part of the North Sea than previ- km of subbottom profiles, acquired between ously suggested and that North Sea ice underwent a dramatic disintegration ~18,500 yr ago. 2005 and 2014 by the University of Bergen This was triggered by grounding-line retreat of the Norwegian Channel Ice Stream, which (Norway) with R/V G.O. Sars using a Kongs- debuttressed adjacent ice masses, and led to an unzipping of the BIS and FIS accompanied by berg TOPAS (parametric subbottom profiler) drainage of a large ice-dammed lake.
    [Show full text]
  • Deglaciation of Nova Scotia: Stratigraphy and Chronology of Lake Sediment Cores and Buried Organic Sections
    Document generated on 09/28/2021 4:12 a.m. Géographie physique et Quaternaire Deglaciation of Nova Scotia: Stratigraphy and chronology of lake sediment cores and buried organic sections La déglaciation en Nouvelle-Écosse : stratigraphie et chronologie à partir de carottes sédimentaires lacustres et de coupes de matériaux organiques enfouies. Die Enteisung von Nova Scotia: Stratigraphie und Chronologie von See-Sedimentkernen und Torf-Profilen. Rudolph R. Stea and Robert J. Mott Volume 52, Number 1, 1998 Article abstract The deglaciation of Nova Scotia is reconstructed using the AMS-dated URI: https://id.erudit.org/iderudit/004871ar chronology of lake sediments and buried organic sections exposed in the DOI: https://doi.org/10.7202/004871ar basins of former glacial lakes. Ice cleared out of the Bay of Fundy around 13.5 ka, punctuated by a brief read- vance ca. 13-12.5 ka (Ice Flow Phase 4). Glacial See table of contents Lake Shubenacadie (1) formed in central Nova Scotia, impounded by a lobe of ice covering the northern Bay of Fundy outlet. Drainage was re-routed to the Atlantic Ocean until the Fundy outlet became ice free after 12 ka. When this Publisher(s) lake drained, bogs and fens formed on the lake plain during climatic warming. Organic sediment (gyttja) began to accumulate in lake basins throughout Nova Les Presses de l'Université de Montréal Scotia. Glacierization during the Younger Dryas period (ca. 10.8 ka) resulted in the inundation of lakes and lake plains with mineral sediment. The nature and ISSN intensity of this mineral sediment flux or "oscillation" varies from south to northern regions.
    [Show full text]
  • Modeling the Deglaciation of the Green Bay Lobe of the Southern Laurentide Ice Sheet
    Modeling the deglaciation of the Green Bay Lobe of the southern Laurentide Ice Sheet CORNELIA WINGUTH, DAVID M. MICKELSON, PATRICK M. COLGAN AND BENJAMIN J. C. LAABS Winguth, C., Mickelson, D. M., Colgan, P. M. & Laabs, B. J. C. 2004 (February): Modeling the deglaciation of the Green Bay Lobe of the southern Laurentide Ice Sheet. Boreas, Vol. 33, pp. 34–47. Oslo. ISSN 0300- 9483. We use a time-dependent two-dimensional ice-flow model to explore the development of the Green Bay Lobe, an outlet glacier of the southern Laurentide Ice Sheet, leading up to the time of maximum ice extent and during subsequent deglaciation (c. 30 to 8 cal. ka BP). We focus on conditions at the ice-bed interface in order to evaluate their possible impact on glacial landscape evolution. Air temperatures for model input have been reconstructed using the GRIP 18O record calibrated to speleothem records from Missouri that cover the time periods of c.65to 30 cal. ka BP and 13.25 to 12.4 cal. ka BP. Using that input, the known ice extents during maximum glaciation and early deglaciation can be reproduced reasonably well. The model fails, however, to reproduce short-term ice margin retreat and readvance events during later stages of deglaciation. Model results indicate that the area exposed after the retreat of the Green Bay Lobe was characterized by permafrost until at least 14 cal. ka BP. The extensive drumlin zones that formed behind the ice margins of the outermost Johnstown phase and the later Green Lake phase are associated with modeled ice margins that were stable for at least 1000 years, high basal shear stresses (c.
    [Show full text]
  • Nunataks As Barriers to Ice Flow: Implications for Palaeo Ice-Sheet
    https://doi.org/10.5194/tc-2021-173 Preprint. Discussion started: 11 June 2021 c Author(s) 2021. CC BY 4.0 License. Nunataks as barriers to ice flow: implications for palaeo ice-sheet reconstructions Martim Mas e Braga1,2, Richard Selwyn Jones3,4, Jennifer C. H. Newall1,2, Irina Rogozhina5, Jane L. Andersen6, Nathaniel A. Lifton7,8, and Arjen P. Stroeven1,2 1Geomorphology & Glaciology, Department of Physical Geography, Stockholm University, Stockholm, Sweden 2Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden 3Department of Geography, Durham University, Durham, UK 4School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia 5Department of Geography, Norwegian University of Science and Technology, Trondheim, Norway 6Department of Geoscience, Aarhus University, Aarhus, Denmark 7Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, USA 8Department of Physics and Astronomy, Purdue University, West Lafayette, USA Correspondence: Martim Mas e Braga ([email protected]) Abstract. Numerical models predict that discharge from the polar ice sheets will become the largest contributor to sea level rise over the coming centuries. However, the predicted amount of ice discharge and associated thinning depends on how well ice sheet models reproduce glaciological processes, such as ice flow in regions of large topographic relief, where ice flows around bedrock summits (i.e. nunataks) and through outlet glaciers. The ability of ice sheet models to capture long-term ice loss is 5 best tested by comparing model simulations against geological data. A benchmark for such models is ice surface elevation change, which has been constrained empirically at nunataks and along margins of outlet glaciers using cosmogenic exposure dating.
    [Show full text]
  • Teacher's Guide for FACES
    Teacher’s Guide for FACES January 2015: Why Greenland Matters Prepared by Heather Bode Heather Bode enjoys writing non-fiction for children and general interest articles for adults. She worked in education for 16 years before switching her focus to writing. Heather lives in Montana with her husband and five children. Getting Started Read “About the Cover” below the Mystery Photo. Compare/contrast the population of Greenland to your country/state/city/town. Pose the question: Why DOES Greenland matter? Play Two Truths and a Lie: Read the following statements. Students must guess which statements are true and which one is a lie. Greenland is the largest island on earth. Greenland is an independent nation. Greenland is mostly covered in ice. (The second statement is the lie. Decide whether you want to reveal the answer or have the students figure it out as they make their way through the issue.) High Five (RI1) Classify the five points using the FACES tagline. What does each point discuss: the people, places, or culture of Greenland? At a Glance (RL3) Describe Greenland’s geography in five words or less. Describe the geography of your region in five words or less. Compare/contrast the two. (RL1/RI1) Geography Theme: Location! Find Greenland’s absolute location using latitude and longitude. Describe Greenland’s relative location. Unicorns of the Sea: Narwhals (RL4) Vocabulary: plankton, echolocation, spiral, incisor, tusk, scepter, pods (RL7) Use the pictures accompanying the article to discuss attributes of narwhals that aid their survival. (W1) What’s your opinion? What is the purpose of the narwhal’s tusk? Support your opinion with reasons.
    [Show full text]