Physical Properties of Shallow Ice Cores from Antarctic and Sub-Antarctic Islands
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Region 19 Antarctica Pg.781
Appendix B – Region 19 Country and regional profiles of volcanic hazard and risk: Antarctica S.K. Brown1, R.S.J. Sparks1, K. Mee2, C. Vye-Brown2, E.Ilyinskaya2, S.F. Jenkins1, S.C. Loughlin2* 1University of Bristol, UK; 2British Geological Survey, UK, * Full contributor list available in Appendix B Full Download This download comprises the profiles for Region 19: Antarctica only. For the full report and all regions see Appendix B Full Download. Page numbers reflect position in the full report. The following countries are profiled here: Region 19 Antarctica Pg.781 Brown, S.K., Sparks, R.S.J., Mee, K., Vye-Brown, C., Ilyinskaya, E., Jenkins, S.F., and Loughlin, S.C. (2015) Country and regional profiles of volcanic hazard and risk. In: S.C. Loughlin, R.S.J. Sparks, S.K. Brown, S.F. Jenkins & C. Vye-Brown (eds) Global Volcanic Hazards and Risk, Cambridge: Cambridge University Press. This profile and the data therein should not be used in place of focussed assessments and information provided by local monitoring and research institutions. Region 19: Antarctica Description Figure 19.1 The distribution of Holocene volcanoes through the Antarctica region. A zone extending 200 km beyond the region’s borders shows other volcanoes whose eruptions may directly affect Antarctica. Thirty-two Holocene volcanoes are located in Antarctica. Half of these volcanoes have no confirmed eruptions recorded during the Holocene, and therefore the activity state is uncertain. A further volcano, Mount Rittmann, is not included in this count as the most recent activity here was dated in the Pleistocene, however this is geothermally active as discussed in Herbold et al. -
Calving Processes and the Dynamics of Calving Glaciers ⁎ Douglas I
Earth-Science Reviews 82 (2007) 143–179 www.elsevier.com/locate/earscirev Calving processes and the dynamics of calving glaciers ⁎ Douglas I. Benn a,b, , Charles R. Warren a, Ruth H. Mottram a a School of Geography and Geosciences, University of St Andrews, KY16 9AL, UK b The University Centre in Svalbard, PO Box 156, N-9171 Longyearbyen, Norway Received 26 October 2006; accepted 13 February 2007 Available online 27 February 2007 Abstract Calving of icebergs is an important component of mass loss from the polar ice sheets and glaciers in many parts of the world. Calving rates can increase dramatically in response to increases in velocity and/or retreat of the glacier margin, with important implications for sea level change. Despite their importance, calving and related dynamic processes are poorly represented in the current generation of ice sheet models. This is largely because understanding the ‘calving problem’ involves several other long-standing problems in glaciology, combined with the difficulties and dangers of field data collection. In this paper, we systematically review different aspects of the calving problem, and outline a new framework for representing calving processes in ice sheet models. We define a hierarchy of calving processes, to distinguish those that exert a fundamental control on the position of the ice margin from more localised processes responsible for individual calving events. The first-order control on calving is the strain rate arising from spatial variations in velocity (particularly sliding speed), which determines the location and depth of surface crevasses. Superimposed on this first-order process are second-order processes that can further erode the ice margin. -
Article Is Available On- J.: the International Bathymetric Chart of the Southern Ocean Line At
The Cryosphere, 14, 1399–1408, 2020 https://doi.org/10.5194/tc-14-1399-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Getz Ice Shelf melt enhanced by freshwater discharge from beneath the West Antarctic Ice Sheet Wei Wei1, Donald D. Blankenship1, Jamin S. Greenbaum1, Noel Gourmelen2, Christine F. Dow3, Thomas G. Richter1, Chad A. Greene4, Duncan A. Young1, SangHoon Lee5, Tae-Wan Kim5, Won Sang Lee5, and Karen M. Assmann6,a 1Institute for Geophysics and Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, Texas, USA 2School of GeoSciences, University of Edinburgh, Edinburgh, UK 3Department of Geography and Environmental Management, University of Waterloo, Waterloo, Ontario, Canada 4Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA 5Korea Polar Research Institute, Incheon, South Korea 6Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden apresent address: Institute of Marine Research, Tromsø, Norway Correspondence: Wei Wei ([email protected]) Received: 18 July 2019 – Discussion started: 26 July 2019 Revised: 8 March 2020 – Accepted: 10 March 2020 – Published: 27 April 2020 Abstract. Antarctica’s Getz Ice Shelf has been rapidly thin- 1 Introduction ning in recent years, producing more meltwater than any other ice shelf in the world. The influx of fresh water is The Getz Ice Shelf (Getz herein) in West Antarctica is over known to substantially influence ocean circulation and bi- 500 km long and 30 to 100 km wide; it produces more fresh ological productivity, but relatively little is known about water than any other source in Antarctica (Rignot et al., 2013; the factors controlling basal melt rate or how basal melt is Jacobs et al., 2013), and in recent years its melt rate has spatially distributed beneath the ice shelf. -
A Globally Complete Inventory of Glaciers
Journal of Glaciology, Vol. 60, No. 221, 2014 doi: 10.3189/2014JoG13J176 537 The Randolph Glacier Inventory: a globally complete inventory of glaciers W. Tad PFEFFER,1 Anthony A. ARENDT,2 Andrew BLISS,2 Tobias BOLCH,3,4 J. Graham COGLEY,5 Alex S. GARDNER,6 Jon-Ove HAGEN,7 Regine HOCK,2,8 Georg KASER,9 Christian KIENHOLZ,2 Evan S. MILES,10 Geir MOHOLDT,11 Nico MOÈ LG,3 Frank PAUL,3 Valentina RADICÂ ,12 Philipp RASTNER,3 Bruce H. RAUP,13 Justin RICH,2 Martin J. SHARP,14 THE RANDOLPH CONSORTIUM15 1Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA 2Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA 3Department of Geography, University of ZuÈrich, ZuÈrich, Switzerland 4Institute for Cartography, Technische UniversitaÈt Dresden, Dresden, Germany 5Department of Geography, Trent University, Peterborough, Ontario, Canada E-mail: [email protected] 6Graduate School of Geography, Clark University, Worcester, MA, USA 7Department of Geosciences, University of Oslo, Oslo, Norway 8Department of Earth Sciences, Uppsala University, Uppsala, Sweden 9Institute of Meteorology and Geophysics, University of Innsbruck, Innsbruck, Austria 10Scott Polar Research Institute, University of Cambridge, Cambridge, UK 11Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA 12Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada 13National Snow and Ice Data Center, University of Colorado, Boulder, CO, USA 14Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada 15A complete list of Consortium authors is in the Appendix ABSTRACT. The Randolph Glacier Inventory (RGI) is a globally complete collection of digital outlines of glaciers, excluding the ice sheets, developed to meet the needs of the Fifth Assessment of the Intergovernmental Panel on Climate Change for estimates of past and future mass balance. -
Glaciers and Their Significance for the Earth Nature - Vladimir M
HYDROLOGICAL CYCLE – Vol. IV - Glaciers and Their Significance for the Earth Nature - Vladimir M. Kotlyakov GLACIERS AND THEIR SIGNIFICANCE FOR THE EARTH NATURE Vladimir M. Kotlyakov Institute of Geography, Russian Academy of Sciences, Moscow, Russia Keywords: Chionosphere, cryosphere, glacial epochs, glacier, glacier-derived runoff, glacier oscillations, glacio-climatic indices, glaciology, glaciosphere, ice, ice formation zones, snow line, theory of glaciation Contents 1. Introduction 2. Development of glaciology 3. Ice as a natural substance 4. Snow and ice in the Nature system of the Earth 5. Snow line and glaciers 6. Regime of surface processes 7. Regime of internal processes 8. Runoff from glaciers 9. Potentialities for the glacier resource use 10. Interaction between glaciation and climate 11. Glacier oscillations 12. Past glaciation of the Earth Glossary Bibliography Biographical Sketch Summary Past, present and future of glaciation are a major focus of interest for glaciology, i.e. the science of the natural systems, whose properties and dynamics are determined by glacial ice. Glaciology is the science at the interfaces between geography, hydrology, geology, and geophysics. Not only glaciers and ice sheets are its subjects, but also are atmospheric ice, snow cover, ice of water basins and streams, underground ice and aufeises (naleds). Ice is a mono-mineral rock. Ten crystal ice variants and one amorphous variety of the ice are known.UNESCO Only the ice-1 variant has been – reve EOLSSaled in the Nature. A cryosphere is formed in the region of interaction between the atmosphere, hydrosphere and lithosphere, and it is characterized bySAMPLE negative or zero temperature. CHAPTERS Glaciology itself studies the glaciosphere that is a totality of snow-ice formations on the Earth's surface. -
FRISP 2018 PROGRAM (Abstracts Below)
FRISP 2018 PROGRAM (Abstracts below) Monday 3rd 19h00: Arrival in Aussois. 20h00: Dinner. Tuesday 4th 7h30 – 8h30: Breakfast. 8h30 – 8h40: Welcome and Introduction (JB. Sallée & N. Joudain) 8h40 – 10h20: 5 presentations. [Weddell/FRIS, 1st part] • Svenja Ryan. • Markus Janout. • Tore Hattermann. • Camille Akhoudas. • Kaitlin Naughten. 10h20 – 10h40: Tea or coffee Break. 10h40 – 12h00: 4 presentations. [Weddell/FRIS, 2nd part] • Kjersti Daae. • Keith Nicholls. • Ole Zeising. • Lukrecia Stulic. 12h00 – 14h00: Lunch. 14h00 – 16h00: 6 presentations. [Greenland] • Lu An. • Jérémie Mouginot. • Irena Vankova. • Fiama Straneo. • Julia Christmann. • Donald Slater. 16h00 – 18h00: Posters. 19h00: Dinner. Wednesday 5th 7h30 – 8h30: Breakfast. 8h30 – 10h10: 5 presentations. [Processes and parameterizations] • Lionel Favier. • Adrian Jenkins. • Catherine Vreugdenhil. • Lucie Vignes. • Stephen Warren. 10h10 – 10h40: Tea or coffee break. 10h40 – 12h00: 4 presentations. [Ross] • Stevens Craig. • Alena Malyarenko. • Carolyn Branecky Begeman. • Justin Lawrence. 12h00 – 14h00: Lunch. 14h00 – 16h00: 6 presentations. [Amundsen] • Karen Assmann. • Tae-Wan Kim. • Yoshihiro Nakayama. • Paul Holland. • Alessandro Silvano. • Won Sang Lee. 16h00 – 18h00: Posters. 19h00: Dinner. Thursday 6th 7h30 – 8h30: Breakfast. 8h30 – 9h50: 4 presentations. [Antarctic ice sheet/Southern Ocean] • Ole Richter. • Xylar Asay-Davis. • Bertie Miles. • William Lipscomb. 9h50 – 10h20: Tea or coffee Break. 10h20 – 11h20: 3 presentations [East Antarctica] • Minowa Masahiro. • Chad Greene. -
Edges of Ice-Sheet Glaciology
Important Things Ice Sheets Do, but Ice Sheet Models Don’t Dr. Robert Bindschadler Chief Scientist Hydrospheric and Biospheric Sciences Laboratory NASA Goddard Space Flight Center [email protected] I’ll talk about • Why we need models – from a non-modeler • Why we need good models – recent observations have destroyed confidence in present models • Recent ice-sheet surprises • Responsible physical processes “…understanding of (possible future rapid dynamical changes in ice flow) is too limited to assess their likelihood or provide a best estimate or an upper bound for sea level rise.” IPCC Fourth Assessment Report, Summary for Policy Makers (2007) Future Sea Level is likely underestimated A1B IPCC AR4 (2007) Ice Sheets matter Globally Source: CReSIS and NASA Land area lost by 1-meter rise in sea level Impact of 1-meter sea level rise: Source: Anthoff et al., 2006 Maldives 20th Century Greenland Ice Sheet Sea level Change (mm/a) -1 0 +1 accumulation 450 Gt/a melting 225 Gt/a ice flow 225 Gt/a Approximately in “mass balance” 21st Century Greenland Ice Sheet Sea level Change (mm/a) -1 0 +1 accumulation melting ice flow Things could get a little better or a lot worse Increased ice flow will dominate the future rate of change A History Lesson • Less ice in HIGH SEA LEVEL Less warmer ice climates • Ice sheets More shrink faster LOW ice than they TEMPERATURE WARM grow • Sea level change is not COLD THEN NOW smooth Time Decreasing Mass Balance (Source: Luthcke et al., unpub.) Greenland Ice Sheet Mass Balance GREENLAND (Source: IPCC FAR) Antarctic Ice Sheet Mass Balance ANTARCTICA (Source: IPCC FAR) Pace of ice sheet changes have astonished experts is the common agent behind these changes Ice sheets HATE water! Fastest Flow at the Edges Interior: 1000’s meters thick and slow Perimeter: 100’s meters thick and fast Source: Rignot and Thomas Response time and speed of perturbation propagation are tied directly to ice flow speed 1. -
New Zealand Subantarctic Islands Research Strategy
New Zealand Subantarctic Islands Research Strategy SOUTHLAND CONSERVANCY New Zealand Subantarctic Islands Research Strategy Carol West MAY 2005 Cover photo: Recording and conservation treatment of Butterfield Point fingerpost, Enderby Island, Auckland Islands Published by Department of Conservation PO Box 743 Invercargill, New Zealand. CONTENTS Foreword 5 1.0 Introduction 6 1.1 Setting 6 1.2 Legal status 8 1.3 Management 8 2.0 Purpose of this research strategy 11 2.1 Links to other strategies 12 2.2 Monitoring 12 2.3 Bibliographic database 13 3.0 Research evaluation and conditions 14 3.1 Research of benefit to management of the Subantarctic islands 14 3.2 Framework for evaluation of research proposals 15 3.2.1 Research criteria 15 3.2.2 Risk Assessment 15 3.2.3 Additional points to consider 16 3.2.4 Process for proposal evaluation 16 3.3 Obligations of researchers 17 4.0 Research themes 18 4.1 Theme 1 – Natural ecosystems 18 4.1.1 Key research topics 19 4.1.1.1 Ecosystem dynamics 19 4.1.1.2 Population ecology 20 4.1.1.3 Disease 20 4.1.1.4 Systematics 21 4.1.1.5 Biogeography 21 4.1.1.6 Physiology 21 4.1.1.7 Pedology 21 4.2 Theme 2 – Effects of introduced biota 22 4.2.1 Key research topics 22 4.2.1.1 Effects of introduced animals 22 4.2.1.2 Effects of introduced plants 23 4.2.1.3 Exotic biota as agents of disease transmission 23 4.2.1.4 Eradication of introduced biota 23 4.3 Theme 3 – Human impacts and social interaction 23 4.3.1 Key research topics 24 4.3.1.1 History and archaeology 24 4.3.1.2 Human interactions with wildlife 25 4.3.1.3 -
Antarctic Treaty Handbook
Annex Proposed Renumbering of Antarctic Protected Areas Existing SPA’s Existing Site Proposed Year Annex V No. New Site Management Plan No. Adopted ‘Taylor Rookery 1 101 1992 Rookery Islands 2 102 1992 Ardery Island and Odbert Island 3 103 1992 Sabrina Island 4 104 Beaufort Island 5 105 Cape Crozier [redesignated as SSSI no.4] - - Cape Hallet 7 106 Dion Islands 8 107 Green Island 9 108 Byers Peninsula [redesignated as SSSI no. 6] - - Cape Shireff [redesignated as SSSI no. 32] - - Fildes Peninsula [redesignated as SSSI no.5] - - Moe Island 13 109 1995 Lynch Island 14 110 Southern Powell Island 15 111 1995 Coppermine Peninsula 16 112 Litchfield Island 17 113 North Coronation Island 18 114 Lagotellerie Island 19 115 New College Valley 20 116 1992 Avian Island (was SSSI no. 30) 21 117 ‘Cryptogram Ridge’ 22 118 Forlidas and Davis Valley Ponds 23 119 Pointe-Geologic Archipelago 24 120 1995 Cape Royds 1 121 Arrival Heights 2 122 Barwick Valley 3 123 Cape Crozier (was SPA no. 6) 4 124 Fildes Peninsula (was SPA no. 12) 5 125 Byers Peninsula (was SPA no. 10) 6 126 Haswell Island 7 127 Western Shore of Admiralty Bay 8 128 Rothera Point 9 129 Caughley Beach 10 116 1995 ‘Tramway Ridge’ 11 130 Canada Glacier 12 131 Potter Peninsula 13 132 Existing SPA’s Existing Site Proposed Year Annex V No. New Site Management Plan No. Adopted Harmony Point 14 133 Cierva Point 15 134 North-east Bailey Peninsula 16 135 Clark Peninsula 17 136 North-west White Island 18 137 Linnaeus Terrace 19 138 Biscoe Point 20 139 Parts of Deception Island 21 140 ‘Yukidori Valley’ 22 141 Svarthmaren 23 142 Summit of Mount Melbourne 24 118 ‘Marine Plain’ 25 143 Chile Bay 26 144 Port Foster 27 145 South Bay 28 146 Ablation Point 29 147 Avian Island [redesignated as SPA no. -
Glacier Change Along West Antarctica's Marie Byrd Land Sector
Glacier change along West Antarctica’s Marie Byrd Land Sector and links to inter-decadal atmosphere-ocean variability Frazer D.W. Christie1, Robert G. Bingham1, Noel Gourmelen1, Eric J. Steig2, Rosie R. Bisset1, Hamish D. Pritchard3, Kate Snow1 and Simon F.B. Tett1 5 1School of GeoSciences, University of Edinburgh, Edinburgh, UK 2Department of Earth & Space Sciences, University of Washington, Seattle, USA 3British Antarctic Survey, Cambridge, UK Correspondence to: Frazer D.W. Christie ([email protected]) Abstract. Over the past 20 years satellite remote sensing has captured significant downwasting of glaciers that drain the West 10 Antarctic Ice Sheet into the ocean, particularly across the Amundsen Sea Sector. Along the neighbouring Marie Byrd Land Sector, situated west of Thwaites Glacier to Ross Ice Shelf, glaciological change has been only sparsely monitored. Here, we use optical satellite imagery to track grounding-line migration along the Marie Byrd Land Sector between 2003 and 2015, and compare observed changes with ICESat and CryoSat-2-derived surface elevation and thickness change records. During the observational period, 33% of the grounding line underwent retreat, with no significant advance recorded over the remainder 15 of the ~2200 km long coastline. The greatest retreat rates were observed along the 650-km-long Getz Ice Shelf, further west of which only minor retreat occurred. The relative glaciological stability west of Getz Ice Shelf can be attributed to a divergence of the Antarctic Circumpolar Current from the continental-shelf break at 135° W, coincident with a transition in the morphology of the continental shelf. Along Getz Ice Shelf, grounding-line retreat reduced by 68% during the CryoSat-2 era relative to earlier observations. -
Late Quaternary Volcanic Activity in Marie Byrd Land: Potential 40Ar/39Ar-Dated Time Horizons in West Antarctic Ice and Marine Cores
Late Quaternary volcanic activity in Marie Byrd Land: Potential 40Ar/39Ar-dated time horizons in West Antarctic ice and marine cores T. I. Wilch* Department of Geological Sciences, Albion College, Albion, Michigan 49224 W. C. McIntosh Department of Earth and Environmental Science, New Mexico Institute of Mining and Technology, and New Mexico Bureau of Mines and Mineral Resources, Socorro, New Mexico 87801 N. W. Dunbar New Mexico Bureau of Mines and Mineral Resources, Socorro, New Mexico 87801 ABSTRACT More than 12 40Ar/39Ar-dated tephra lay- ies is to determine the basal age of the ice sheet. ers, exposed in bare ice on the summit ice cap The 1968 Byrd Station ice core in the West Late Quaternary volcanic activity at three of Mount Moulton, 30 km from their inferred Antarctic Ice Sheet has an inferred basal age of major alkaline composite volcanoes in Marie source at Mount Berlin, range in age from 492 only 74 ka (Hammer et al., 1994). The exten- Byrd Land, West Antarctica, is dominated by to 15 ka. These englacial tephra layers provide sive lateral flow of ice from the ice divide area explosive eruptions, many capable of deposit- a minimum age of 492 ka for the oldest iso- to Byrd Station may have removed or disturbed ing ash layers as regional time-stratigraphic topically dated ice in West Antarctica. This much of the basal ice record. Consequently, the horizons in the West Antarctic Ice Sheet and well-dated section of locally derived glacial ice 74 ka date of the Byrd core provides only a in Southern Ocean marine sediments. -
Balleny Paper
XXIII ATCM/WP31 May, 1999 Original: English Agenda Item 7f) CEP II Agenda Item 5e) Proposed Balleny Island Specially Protected Area Submitted by New Zealand Error! Reference source not found. Proposed Balleny Island Specially Protected Area Summary New Zealand proposes that consideration be given to Specially Protected Area No.4 concerning Sabrina Island in the Balleny Islands being enlarged to include other Balleny Islands, together with a marine area surrounding the islands. A copy of the draft management plan is provided for information and consultation. The designation of an enlarged SPA is considered necessary to protect the unique and special ecological, scientific and aesthetic values of the area and to establish an archipelagic SPA in the Ross Sea region. Background At the Fourth Antarctic Treaty Consultative Meeting in Santiago in 1966, a small island in the Balleny Islands was designated as Specially Protected Area No. 4. Sabrina Island was accorded this status in recognition that the Balleny Islands are the most northerly Antarctic land in the Ross Sea region and support fauna and flora which reflect many circumpolar distributions at this latitude. The Balleny Islands (together with Scott Island) are the only truly marine or oceanic islands (rather than continental islands) on this side of Antarctica making them distinctive from any neighbouring areas. Located 250km off the coast of Antarctica in the northern Ross Sea, the Balleny Islands are a rare “oasis” of land in the Southern Ocean and their position is far enough north to be directly in the path of circumpolar ocean currents. Consequently their presence is likely to create upwellings, which tend to bring nutrient-rich deep water closer to the surface, which in turn makes the area biologically very productive.