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Showing 1 to 20 of 50 for “"Antarctic Ice Sheet"”.
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Monitoring the Antarctic Ice Sheet From Space
The Antarctic ice sheet is a geophysically - and in an age of growing concern about global warming, geopolitically - important portion of Earth. The composition and dynamics of the Antarctic ice sheet influence global climate patterns, global sea level and the planet's radiation budget. Recent …
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The Topography and Flow of the Antarctic Ice Sheet
… to investigate the form and topography of the Antarctic ice sheet and to relate these to the physical processes of ice flow and basal conditions. Topographic roughness typically increases towards the thin ice of coastal reg ions as surface undulation wav el eng ths decrease and amplitudes …
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The recent history of the Antarctic ice sheet : constraints from sea-level change
The rheology of the earth and the history of ice sheets, which have a major contributing role in climate change, are both subjects of considerable interest in earth sciences, and the study of sea-level change provides insight into both. Sea-level change since the last glacial maximum (LGM), about …
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The recent history of the Antarctic ice sheet : constraints from sea-level change
The rheology of the earth and the history of ice sheets, which have a major contributing role in climate change, are both subjects of considerable interest in earth sciences, and the study of sea-level change provides insight into both. Sea-level change since the last glacial maximum (LGM), about …
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Constraining the pathways and fluxes of subglacial meltwater beneath the palaeo-Antarctic Ice Sheet
The flow, flux and routing of water beneath ice sheets has a fundamental impact on their mass-loss behaviour. Relict channelised forms observed on the Antarctic continental shelf imply that there was an active subglacial hydrological system beneath the palaeo Antarctic Ice Sheet. The dimensions of …
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Linearity of the Climate System Response to Antarctic Topography Change
… of the global climate system to changes in Antarctic topography. Models range in complexity from an atmospheric dry dynamical core to a slab-ocean global climate model with idealized West Antarctic ice sheet topography changes and experiments were conducted where topography was either …
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The Evolution and Impact of Weddell Sea Deep Water
The interaction between the Antarctic Ice Sheet and the Southern Ocean is of major importance for changes in Earth’s climate. The Antarctic Ice Sheet is largely marine based and grounded below sea level, which makes it especially vulnerable for sea-level forcing and ocean warming. In turn, the …
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Quaternary grounding-line fluctuations in Antarctica
The West Antarctic Ice Sheet may be prone to rapid collapse under climates warmer than today due to a dynamic instability at the grounding line, where the ice sheet goes afloat over seawater. However, there is to-date no conclusive evidence that the ice sheet has gone away in last few million …
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Meteoric 10Be as a Tracer for Subglacial Chemical Weathering in East Antarctica
Subglacial chemical processes in Antarctica are potentially significant contributors to global geochemical cycles, but current understanding of their scale and nature is limited. A sequential chemical extraction procedure was developed and tested to investigate the utility of meteoric 10Be as a …
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ANTARCTIC GLACIAL CHRONOLOGY REFLECTED IN THE OLIGOCENE THROUGH PLIOCENE SEDIMENTARY SECTION IN THE ROSS SEA
Over 24% of the ice surface area covering East and West Antarctica drains into the Ross Sea and supplies the Ross Ice Shelf. The dominant proportion of this ice originates from the West Antarctic subcontinent. Thus, any change in the glacial regime in West Antarctica, and to a lesser extent East …
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Sea-ice and ice-shelf variability in the Amundsen Sea Embayment, West Antarctica
Global sea-level rise contributed by Antarctic ice-mass loss could soon outpace all other sources. The ice-mass-loss signal of the Antarctic Ice Sheet is dominated by the Amundsen Sea Embayment (ASE) in West Antarctica. Ice shelves in the ASE influence the ice-mass-loss rates of the Antarctic Ice …
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Patterns and drivers of seasonal land-ice-flow around Antarctica
… documented the multi-annual acceleration of the Antarctic Ice Sheet, and the associated increase in its contribution to global sea level. Unlike the Greenland Ice Sheet, where ice velocity signals are well resolved over both inter- and intra-annual timescales, observations of seasonal signals are …
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Satellite Remote Sensing Investigations into Changing Ice-shelf Extents in the Eastern Weddell Sea Sector of Antarctica
Satellite observations of ice-shelf collapse and related ice-mass drawdown from the Antarctic Peninsula over the past > 3 decades have been unambiguously linked to changes in atmospheric and oceanic processes as a result of anthropogenic climate change. Therefore, contemporary glaciological …
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Airborne geophysical investigations of subglacial structure of West Antarctica
… structure and tectonic evolution of West Antarctica. An airborne geophysical survey in West Antarctica comprising simultaneous Radio Echo Sounding (RES) and magnetics was carried out over -1 M km$^{2}$ of the ice covered area. The collection and reduction of large volumes of RES and …
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Antarctica's Geologic and Ice Sheet History from Isotopic Sedimentary Provenance Studies
… marine sediments located off the margin of East Antarctica provides a means for characterizing the sub-glacial geology obscured by the more than 98% ice cover of the continent. These insights into the geology of East Antarctica in turn provide characterization of sedimentary source areas, the …
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Ocean circulation and carbon cycle dynamics in the Pacific Southern Ocean during Late Pleistocene interglacials
… mass exchange between ocean basins, driving Antarctic Bottom Water and Antarctic Intermediate Water formation and providing the major return path of Circumpolar Deep Water (CDW) to the ocean surface. The Pacific Ocean is the largest aquatic carbon reservoir and having a strong leverage on …
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Radio-echo sounding of Pine Island Glacier, West Antarctica : understanding the past from observations, analysis and modelling of internal layering
… of the fastest and most dynamic glaciers in West Antarctica. The stability of the glacier may thus have profound impact on the overall stability of the West Antarctic Ice Sheet and its contribution to global sea-level rise. This thesis addresses questions concerning the past dynamics of the …
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Radio-echo layering in polar ice sheets
… with layered reflections observed in the Antarctic and Greenland ice sheets during radio-echo sounding. It describes in detail layering seen with 60 and 300 MHz equipment _in the Antarctic ice sheet during three field seasons betwe~n 1974 and 1979, and discusses the effects of …
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The Dynamics of the Late Neogene Antarctic Ice Sheets in the Central Ross Sea using a Multianalytical Approach
With the goal of determining ice sheet history in the central Ross Sea since the late Miocene, the provenance of glacial till from IODP expedition 374 site U1522 was assessed using a suite of three analyses. A total of 3,869 zircons, between 250-63 microns in size, from sixteen different cores were …
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Intra- and Inter-Seasonal Variability of Supra-Glacial 1 Streams and Lakes over the West Greenland Ice Sheet 2 from High-Resolution Satellite Optical Data
<p>The Greenland ice sheet (GrIS) is one of the largest glacial ice masses on Earth, second only to the Antarctic ice sheet. The surface hydrology of the GrIS plays a crucial role on the surface energy and mass balance budgets of the ice sheet as a whole. Surface water, known as supra-glacial …
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