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Palynology of Site 1166, Prydz Bay, East Antarctica1
Cooper, A.K., O’Brien, P.E., and Richter, C. (Eds.) Proceedings of the Ocean Drilling Program, Scientific Results Volume 188 3. PALYNOLOGY OF SITE 1166, PRYDZ BAY, EAST ANTARCTICA1 M.K. Macphail2 and E.M. Truswell3 ABSTRACT Twenty-three core catcher samples from Site 1166 (Hole 1166A) in Prydz Bay were analyzed for their palynomorph content, with the aims of determining the ages of the sequence penetrated, providing informa- tion on the vegetation of the Antarctic continent at this time, and determining the environments under which deposition occurred. Di- nocysts, pollen and spores, and foraminiferal test linings were recov- ered from most samples in the interval from 142.5 to 362.03 meters below seafloor (mbsf). The interval from 142.5 to 258.72 mbsf yielded 1Macphail, M.K., and Truswell, E.M., palynomorphs indicative of a middle–late Eocene age, equivalent to the 2004. Palynology of Site 1166, Prydz lower–middle Nothofagidites asperus Zone of the Gippsland Basin of Bay, East Antarctica. In Cooper, A.K., southeastern Australia. The Prydz Bay sequence represents the first well- O’Brien, P.E., and Richter, C. (Eds.), dated section of this age from East Antarctica. Proc. ODP, Sci. Results, 188, 1–43 Dinocysts belonging to the widespread “Transantarctic Flora” give a [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/ more confident late Eocene age for the interval 142.5–220.5 mbsf. The publications/188_SR/VOLUME/ uppermost two cores within this interval, namely, those from 142.5 and CHAPTERS/013.PDF>. [Cited YYYY- 148.36 mbsf, show significantly higher frequencies of dinocysts than MM-DD] the cores below and suggest that an open marine environment pre- 2Department of Archaeology and vailed at the time of deposition. -
Weather and Climate in the Amundsen Sea Embayment
WEATHER AND CLIMATE IN THE AMUNDSEN SEA EMBAYMENT,WEST ANTARCTICA:OBSERVATIONS, REANALYSES AND HIGH RESOLUTION MODELLING A thesis submitted to the School of Environmental Sciences of the University of East Anglia in partial fulfilment of the requirements for the degree of Doctor of Philosophy RICHARD JONES JANUARY 2018 © This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that use of any information derived there from must be in accordance with current UK Copyright Law. In addition, any quotation or extract must include full attribution. © Copyright 2018 Richard Jones iii ABSTRACT Glaciers within the Amundsen Sea Embayment (ASE) are rapidly retreating and so contributing 10% of current global sea level rise, primarily through basal melting. » Here the focus is atmospheric features that influence the mass balance of these glaciers and their representation in atmospheric models. New radiosondes and surface-based observations show that global reanalysis products contain relatively large biases in the vicinity of Pine Island Glacier (PIG), e.g. near-surface temperatures 1.8 ±C (ERA-I) to 6.8 ±C (MERRA) lower than observed. The reanalyses all underestimate wind speed during orographically-forced strong wind events and struggle to reproduce low-level jets. These biases would contribute to errors in surface heat fluxes and thus the simulated supply of ocean heat leading to PIG melting. Ten new ice cores show that there is no significant trend in accumulation on PIG between 1979 and 2013. RACMO2.3 and four global reanalysis products broadly reproduce the observed time series and the lack of any significant trend. -
Operation Deep Freeze Deep Operation
OPERATION CASE STUDY DEEP FREEZE RESUPPLY OF MCMURDO STATION, ANTARCTICA PROJECT LOCATION: U.S. West Coast, New Zealand, and Antarctica CLIENT: National Science Foundation and US Navy VESSEL: M/V Ocean Giant DURATION: December 2017 to January 2018 CARGO Scientific equipment, ice core samples, and a year’s worth of station supplies. A total of 550 pieces of cargo, weighing in at nearly seven million pounds; including food, building supplies, vehicles, electrical equipment, and parts. OVERVIEW Resupply and return of equipment from Antarctica. The Ocean Giant was preceded by the USCGC Polar Star who cut a resupply channel through more than 60 miles of Antarctic ice in the Ross Sea. This allowed for the annual delivery of operating supplies and fuel for two of the National Science Foundation’s three U.S. research stations in Antarctica. The supplies amounted to nearly 80 percent of the materials needed for the winter period. REGION: THE ARCTIC OPERATION DEEP FREEZE CASE STUDY SYNOPSIS In December 2017, U.S. flag vessel, M/V Ocean Giant departed Port Hueneme, California, loaded with a year’s worth of supplies to support multiple activities in Antarctica. En route, she called Lyttelton, New Zealand, for fuel and to load cargo to support New Zealand’s activities in Antarctica. While underway she proceeded into the polar waters of the Ross Sea and rendezvoused with the ice breaker Polar Star for the final 60 mile transit into McMurdo Station. The channel through the Ross Sea is only navigable for two weeks a year during the southern hemisphere summer. While in McMurdo, she discharged her cargo at one of the most isolated spots in the world to a pier made from ice. -
JTF-SFA Meteorological Support for Operation DEEP FREEZE 2017-2018
Evaluation of Meteorological and Oceanographic support for Joint Task Force Support Forces Antarctica (Operation DEEP FREEZE) Captain Lauren S. Hogg 17 July 2018 Overview • Purpose of Visit • Meteorology Community, Products, and Equipment • Key Findings • JTF-SFA Commander Response Actions • Formal requests for National Science Foundation • Takeaways for Meteorological Community • Acknowledgements Purpose of Visit The goal of this visit was to observe the meteorology and oceanography (METOC) program as a whole and determine what can be done to improve support to JTF-SFA. Primary Focus Areas: • Increase safety of flight, ground, and maritime missions • Improve completion rate of intertheater missions Meteorology Community JMO Navy METOC SOPP Field Camp METOC AMRC Other Science Groups International Partners Lt Col Steven Randle SRC ASC-PAE Dr. Matthew Lazzara and LDB forecasters New Zealand Forecasters Italian Forecasters JMCC UK Forecasters 17th Operational Wx Sq AUS Forecasters ROF (Charleston) ~56 AWSs AWSs 5 Forecasters A-S South Pole Station 3 Observers Eyes-Forward McMurdo Station Observations 1 Met Manager Shackleton Glacier 1 Flight Briefer 2 Observer + 3 Forecasters Augmentee(s) McMurdo Station WAIS Divide 4 Observers 1 Observer + Augmentee(s) Williams Field 1 Observer (Night ops + Sunday) Siple Dome 0 Cert’d Observers Phoenix Field 1 Observer Meteorology in direct support of JTF-SFA (During Ops only) JTF-SFA Meteorology not located in Antarctica USAP Meteorology not directly aligned with JTF-SFA *NOTE: This was specific to the -
1. Leg 189 Summary1
Exon, N.F., Kennett, J.P., Malone, M.J., et al., 2001 Proceedings of the Ocean Drilling Program, Initial Reports Volume 189 1. LEG 189 SUMMARY1 Shipboard Scientific Party2 ABSTRACT The Cenozoic Era is unusual in its development of major ice sheets. Progressive high-latitude cooling during the Cenozoic eventually formed major ice sheets, initially on Antarctica and later in the North- ern Hemisphere. In the early 1970s, a hypothesis was proposed that cli- matic cooling and an Antarctic cryosphere developed as the Antarctic Circumpolar Current progressively thermally isolated the Antarctic continent. This current resulted from the opening of the Tasmanian Gateway south of Tasmania during the Paleogene and the Drake Pas- sage during the earliest Neogene. The five Leg 189 drill sites, in 2463 to 3568 m water depths, tested, refined, and extended the above hypothesis, greatly improving under- standing of Southern Ocean evolution and its relation with Antarctic climatic development. The relatively shallow region off Tasmania is one of the few places where well-preserved and almost-complete marine Cenozoic carbonate-rich sequences can be drilled in present-day lati- tudes of 40°–50°S and paleolatitudes of up to 70°S. The broad geological history of all the sites was comparable, although there are important differences among the three sites in the Indian Ocean and the two sites in the Pacific Ocean, as well as from north to south. In all, 4539 m of core was recovered with an excellent overall recov- ery of 89%, with the deepest core hole penetrating 960 m beneath the seafloor. The entire sedimentary sequence cored is marine and contains a wealth of microfossil assemblages that record marine conditions from the Late Cretaceous (Maastrichtian) to the late Quaternary and domi- nantly terrestrially derived sediments until the earliest Oligocene. -
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. -
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. -
2019 Weddell Sea Expedition
Initial Environmental Evaluation SA Agulhas II in sea ice. Image: Johan Viljoen 1 Submitted to the Polar Regions Department, Foreign and Commonwealth Office, as part of an application for a permit / approval under the UK Antarctic Act 1994. Submitted by: Mr. Oliver Plunket Director Maritime Archaeology Consultants Switzerland AG c/o: Maritime Archaeology Consultants Switzerland AG Baarerstrasse 8, Zug, 6300, Switzerland Final version submitted: September 2018 IEE Prepared by: Dr. Neil Gilbert Director Constantia Consulting Ltd. Christchurch New Zealand 2 Table of contents Table of contents ________________________________________________________________ 3 List of Figures ___________________________________________________________________ 6 List of Tables ___________________________________________________________________ 8 Non-Technical Summary __________________________________________________________ 9 1. Introduction _________________________________________________________________ 18 2. Environmental Impact Assessment Process ________________________________________ 20 2.1 International Requirements ________________________________________________________ 20 2.2 National Requirements ____________________________________________________________ 21 2.3 Applicable ATCM Measures and Resolutions __________________________________________ 22 2.3.1 Non-governmental activities and general operations in Antarctica _______________________________ 22 2.3.2 Scientific research in Antarctica __________________________________________________________ -
S41467-018-05625-3.Pdf
ARTICLE DOI: 10.1038/s41467-018-05625-3 OPEN Holocene reconfiguration and readvance of the East Antarctic Ice Sheet Sarah L. Greenwood 1, Lauren M. Simkins2,3, Anna Ruth W. Halberstadt 2,4, Lindsay O. Prothro2 & John B. Anderson2 How ice sheets respond to changes in their grounding line is important in understanding ice sheet vulnerability to climate and ocean changes. The interplay between regional grounding 1234567890():,; line change and potentially diverse ice flow behaviour of contributing catchments is relevant to an ice sheet’s stability and resilience to change. At the last glacial maximum, marine-based ice streams in the western Ross Sea were fed by numerous catchments draining the East Antarctic Ice Sheet. Here we present geomorphological and acoustic stratigraphic evidence of ice sheet reorganisation in the South Victoria Land (SVL) sector of the western Ross Sea. The opening of a grounding line embayment unzipped ice sheet sub-sectors, enabled an ice flow direction change and triggered enhanced flow from SVL outlet glaciers. These relatively small catchments behaved independently of regional grounding line retreat, instead driving an ice sheet readvance that delivered a significant volume of ice to the ocean and was sustained for centuries. 1 Department of Geological Sciences, Stockholm University, Stockholm 10691, Sweden. 2 Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005, USA. 3 Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA. 4 Department -
Basal Crevasses on the Larsen C Ice Shelf, Antarctica
GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L16504, doi:10.1029/2012GL052413, 2012 Basal crevasses on the Larsen C Ice Shelf, Antarctica: Implications for meltwater ponding and hydrofracture Daniel McGrath,1 Konrad Steffen,1 Harihar Rajaram,2 Ted Scambos,3 Waleed Abdalati,1,4 and Eric Rignot5,6 Received 1 June 2012; revised 20 July 2012; accepted 23 July 2012; published 29 August 2012. [1] A key mechanism for the rapid collapse of both the Lar- thickness (due to the density difference between water and sen A and B Ice Shelves was meltwater-driven crevasse ice), fracturing the ice shelf into numerous elongate icebergs propagation. Basal crevasses, large-scale structural features [van der Veen, 1998, 2007; Scambos et al., 2003, 2009; within ice shelves, may have contributed to this mechanism in Weertman, 1973]. The narrow along-flow width and elon- three important ways: i) the shelf surface deforms due to gated across-flow length of these icebergs distinguishes them modified buoyancy and gravitational forces above the basal from tabular icebergs, and likely facilitates a positive feed- crevasse, creating >10 m deep compressional surface depres- back during the disintegration process, as elongate icebergs sions where meltwater can collect, ii) bending stresses from overturn and initiate further ice shelf calving [MacAyeal the modified shape drive surface crevassing, with crevasses et al., 2003; Guttenberg et al., 2011; Burton et al., 2012]. reaching 40 m in width, on the flanks of the basal-crevasse- [3] Dramatic atmospheric warming over the past five dec- induced trough and iii) the ice thickness is substantially ades has increased surface meltwater production along the reduced, thereby minimizing the propagation distance before a Antarctic Peninsula (AP) [Vaughan et al.,2003;van den full-thickness rift is created. -
The Antarctic Sun, December 25, 2005
December 25, 2005 Scientists seek to label whale species By Steven Profaizer Sun staff Patches of pure white splashed on an inky black body. Two-meter-tall dorsal fin slicing through the water’s surface. An attraction at SeaWorld. A pack hunter with cunning intelligence and stunning power. The killer whale, or orca, is one of the most universally known animals in the world. They are also one of the most wide- spread mammals, second only to humans, and inhabit all of the world’s oceans. Yet scientists are still working to deter- mine how many species of killer whales exist. Only one species is currently rec- ognized, but many people, including researcher Robert Pitman, believe there may be two additional species among the estimated 20,000 to 80,000 killer whales that inhabit Antarctic waters. Pitman is far from the first to believe this: Soviet 5 Union whalers in the early 1980s first Deep Freeze turns 0 observed the killer whales’ differences in diet, preferred habitat and coloring. He By Emily Stone does, however, hope to be part of the team Sun staff that finally solves the mystery. Al Hisey spent one of his first nights at McMurdo Station by accident. Pitman, of the National Oceanic and It was 1955, and he was ferrying supplies by tractor from Navy ships across the Atmospheric Administration, led a team sea ice of McMurdo Sound to the spot on Ross Island where the station was being to Antarctica last year on a two-week mis- built. During one of the first trips, there was a major break in the ice between the sion that used sophisticated technology to fledgling station and the ships. -
95-96 July No. 1
THE ANTARCTICAN SOCIETY 905 NORTH JACKSONVILLE STREET ARLINGTON, VIRGINIA 22205 HONORARY PRESIDENT — MRS. PAUL A. SIPLE ______________________________________________________ Vol. 95-96 July No. 1 Presidents: Dr. Carl R. Eklund, 1959-61 Dr. Paul A. Siple, 1961-62 Mr. Gordon D. Cartwright, 1962-63 Laurence McKinley Gould - "Preeminently a scientist RADM David M. Tyree (Ret.), 1963-64 fascinated by the pursuit of truth and knowledge, Mr. George R. Toney, 1964-65 Mr. Morton J. Rubin, 1965-66 he has the spirit of the scholar, the soul of the Dr. Albert P. Crary, 1966-68 poet and adventurer, and a special ability to com- Dr. Henry M. Dater, 1968-70 Mr.George A.Doumani,1970-71 municate his passion for learning to his students." Dr. William J. L. Sladen, 1971-73 Mr. Peter F. Bermel, 1973-75 Dr. Kenneth J. Bertrand, 1975-77 Mrs. Paul A. Siple, 1977-78 Dr. Paul C. Dalrymple, 1978-80 Dr. Meredith F. Burrill, 1980-82 Dr. Mort D. Turner, 1982-84 Dr. Edward P. Todd, 1984-86 LAURENCE McKINLEY GOULD Mr. Robert H. T. Dodson, 1986-88 Dr. Robert H. Rutford, 1988-90 August 22, 1896 - June 21, 1995 Mr. Guy G. Guthridge, 1990-92 Dr. Polly A. Penhale, 1992-94 Mr. Tony K. Meunier, 1994-96 PAUL-EMILE VICTOR Honorary Members: June 27, 1907 - March 7, 1995 Ambassador Paul C. Daniels Dr. Laurence McKinley Gould Count Emilio Pucci Sir Charles S. Wright Mr. Hugh Blackwell Evans Dr. Henry M. Dater COLLEAGUES AND PEERS WHO PRECEDED LARRY Mr. August Howard Mr. Amory H. "Bud" Waite, Jr. Dr.