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2. A Reconciled Estimate of Ice-Sheet Mass Balance

Author

Shepherd, Andrew, Ivins, Erik R, A, Geruo, Barletta, Valentina R, Bentley, Mike J, Bettadpur, Srinivas, Briggs, Kate H, Bromwich, David H, Forsberg, René, Galin, Natalia, Horwath, Martin, Jacobs, Stan, Joughin, Ian, King, Matt A, Lenaerts, Jan TM, Li, Jilu, Ligtenberg, Stefan RM, Luckman, Adrian, Luthcke, Scott B, McMillan, Malcolm, Meister, Rakia, Milne, Glenn, Mouginot, Jeremie, Muir, Alan, Nicolas, Julien P, Paden, John, Payne, Antony J, Pritchard, Hamish, Rignot, Eric, Rott, Helmut, Sørensen, Louise Sandberg, Scambos, Ted A, Scheuchl, Bernd, Schrama, Ernst JO, Smith, Ben, Sundal, Aud V, van Angelen, Jan H, van de Berg, Willem J, van den Broeke, Michiel R, Vaughan, David G, Velicogna, Isabella, Wahr, John, Whitehouse, Pippa L, Wingham, Duncan J, Yi, Donghui, Young, Duncan, and Zwally, H Jay

Subjects
Climate Action, Antarctic Regions, Climate Change, Geographic Information Systems, Greenland, Ice Cover, General Science & Technology
Abstract

We combined an ensemble of satellite altimetry, interferometry, and gravimetry data sets using common geographical regions, time intervals, and models of surface mass balance and glacial isostatic adjustment to estimate the mass balance of Earth's polar ice sheets. We find that there is good agreement between different satellite methods--especially in Greenland and West Antarctica--and that combining satellite data sets leads to greater certainty. Between 1992 and 2011, the ice sheets of Greenland, East Antarctica, West Antarctica, and the Antarctic Peninsula changed in mass by -142 ± 49, +14 ± 43, -65 ± 26, and -20 ± 14 gigatonnes year(-1), respectively. Since 1992, the polar ice sheets have contributed, on average, 0.59 ± 0.20 millimeter year(-1) to the rate of global sea-level rise.

Published
2012

8. Devil in the Detail

Author

Vaughan, David G., Marshall, Gareth J., Connolley, William M., King, John C., and Mulvaney, Robert

Published
2001

10. Supplementary material to "British Antarctic Survey’s Aerogeophysical Data: Releasing 25 Years of Airborne Gravity, Magnetic, and Radar Datasets over Antarctica"

Author

Frémand, Alice C., primary, Bodart, Julien A., additional, Jordan, Tom A., additional, Ferraccioli, Fausto, additional, Robinson, Carl, additional, Corr, Hugh F. J., additional, Peat, Helen J., additional, Bingham, Robert G., additional, and Vaughan, David G., additional

Published
2022
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13. High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector.

Author

Bodart, Julien A., Bingham, Robert G., Young, Duncan A., MacGregor, Joseph A., Ashmore, David W., Quartini, Enrica, Hein, Andrew S., Vaughan, David G., and Blankenship, Donald D.

Abstract

Modelling the past and future evolution of the West Antarctic Ice Sheet (WAIS) to atmospheric and ocean forcing is challenged by the availability and quality of observed palaeo-boundary conditions. Key potential data for reconstructing past ice-sheet processes on large spatial scales are Internal Reflecting Horizons (IRHs) detected by Radio-Echo Sounding (RES) techniques. When isochronal and dated at ice cores, IRHs can be used to determine palaeo-accumulation rates and patterns. Using a spatially extensive IRH over Pine Island Glacier, Thwaites Glacier, Institute and Möller Ice Streams, and a local layer approximation model, we infer mid-Holocene accumulation rates over the slow-flowing parts of these catchments for the past ~5000 years. By comparing our results with modern climate reanalysis models and observational syntheses, we estimate that accumulation rates over the Amundsen-Weddell-Ross divide were on average 18% higher than modern rates during the mid-Holocene. However, no significant spatial changes in the accumulation pattern were observed. These higher mid-Holocene accumulation-rate estimates match previous palaeo-accumulation estimates from ice-core and targeted RES surveys over the ice divide, and also coincide with periods of grounding-line re-advance during the Holocene over the Weddell and Ross Sea sectors. Our results highlight the need for ice-sheet models to account for time-varying accumulation rates across the WAIS during the Holocene to provide better estimates of its contribution to past sea-level rise. [ABSTRACT FROM AUTHOR]

Published
2022
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17. Summary for Policymakers

Author

Alexander, Lisa V, Allen, Simon K, Bindoff, Nathaniel L, Breon, Francois-Marie, Church, John A, Cubasch, Ulrich, Emori, Seita, Forster, Piers, Friedlingstein, Pierre, Gillett, Nathan, Gregory, Jonathan M, Hartmann, Dennis L, Jansen, Eystein, Kirtman, Ben, Knutti, Reto, Kanikicharla, Krishna Kumar, Lemke, Peter, Marotzke, Jochem, Masson-Delmotte, Valerie, Meehl, Gerald A, Mokhov, Igor I, Piao, Shilong, Plattner, Gian-Kasper, Qin, Dahe, Ramaswamy, Venkatachalam, Randall, David, Rhein, Monika, Rojas, Maisa, Sabine, Christopher, Shindell, Drew, Stocker, Thomas F, Talley, Lynne D, Vaughan, David G, Xie, Shang-Ping, Allen, Myles R, Boucher, Olivier, Chambers, Don, Christensen, Jens Hesselbjerg, Ciais, Philippe, Clark, Peter U, Collins, Matthew, Comiso, Josefino C, de Menezes, Viviane Vasconcellos, Feely, Richard A, Fichefet, Thierry, Fiore, Arlene M, Flato, Gregory, Fuglestvedt, Jan, Hegerl, Gabriele, Hezel, Paul J, Johnson, Gregory C, Kaser, Georg, Kattsov, Vladimir, Kennedy, John, Tank, Albert MG Klein, Le Quere, Corinne, Myhre, Gunnar, Osborn, Timothy, Payne, Antony J, Perlwitz, Judith, Power, Scott, Prather, Michael, Rintoul, Stephen R, Rogelj, Joeri, Rusticucci, Matilde, Schulz, Michael, Sedlacek, Jan, Stott, Peter A, Sutton, Rowan, Thorne, Peter W, and Wuebbles, Donald

Published
2014

18. Inland thinning of West Antarctic Ice Sheet steered along subglacial rifts

Author

Bingham, Robert G., Ferraccioli, Fausto, King, Edward C., Larter, Robert D., Pritchard, Hamish D., Smith, Andrew M., and Vaughan, David G.

Subjects
Geodynamics -- Research, Faults (Geology) -- Environmental aspects, Surface-ice melting -- Environmental aspects, Ice sheets -- Environmental aspects, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Current ice loss from the West Antarctic Ice Sheet (WAIS) accounts for about ten per cent of observed global sea-level rise (1). Losses are dominated by dynamic thinning, in which [...]

Published
2012
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21. Extensive dynamic thinning on the margins of the Greenland and Antarctic ice sheets

Author

Pritchard, Hamish D., Arthern, Robert J., Vaughan, David G., and Edwards, Laura A.

Subjects
Surface-ice melting -- Analysis, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Many glaciers along the margins of the Greenland and Antarctic ice sheets are accelerating and, for this reason, contribute increasingly to global sea-level rise (1-7). Globally, ice losses contribute ~1.8 mm [yr.sup.-1] (ref. 8), but this could increase if the retreat of ice shelves and tidewater glaciers further enhances the loss of grounded ice (9) or initiates the large-scale collapse of vulnerable parts of the ice sheets (10). Ice loss as a result of accelerated flow, known as dynamic thinning, is so poorly understood that its potential contribution to sea level over the twenty-first century remains unpredictable (11). Thinning on the ice-sheet scale has been monitored by using repeat satellite altimetry observations to track small changes in surface elevation, but previous sensors could not resolve most fast-flowing coastal glaciers (12). Here we report the use of high-resolution ICESat (Ice, Cloud and land Elevation Satellite) laser altimetry to map change along the entire grounded margins of the Greenland and Antarctic ice sheets. To isolate the dynamic signal, we compare rates of elevation change from both fast-flowing and slow-flowing ice with those expected from surface mass-balance fluctuations. We find that dynamic thinning of glaciers now reaches all latitudes in Greenland, has intensified on key Antarctic grounding lines, has endured for decades after ice-shelf collapse, penetrates far into the interior of each ice sheet and is spreading as ice shelves thin by ocean-driven melt. In Greenland, glaciers flowing faster than 100 m [yr.sup.-1] thinned at an average rate of 0.84m [yr.sup.-1], and in the Amundsen Sea embayment of Antarctica, thinning exceeded 9.0 m [yr.sup.-1] for some glaciers. Our results show that the most profound changes in the ice sheets currently result from glacier dynamics at ocean margins., To quantify ice loss from ice sheets, three different methods have so far been used: calculation of flux imbalance from separate measurements of snow accumulation and ice flow velocity, detection [...]

Published
2009

25. East Antarctic ice stream tributary underlain by major sedimentary basin

Author

Bamber, Jonathan L., Ferraccioli, Fausto, Joughin, Ian, Shepherd, Tony, Rippin, David M., Siegert, Martin J., and Vaughan, David G.

Subjects
Antarctica -- Environmental aspects, Marine sediments -- Environmental aspects, Ice sheets -- Environmental aspects, Ice sheets -- Structure, Ice sheets -- Analysis, Earth sciences
Abstract

Marine and rift sediments exert a fundamental control on ice stream flow in the West Antarctic Ice Sheet, and hence on its mass balance and stability. In contrast, most ice streams in the much larger East Antarctic Ice Sheet are thought to be relatively stable features resting on till, perhaps underlain by crystalline rock. Any geological controls on East Antarctic Ice Sheet enhanced flow remain largely unknown. We present aerogeophysical evidence indicating that a region of enhanced ice flow in the interior of the East Antarctic Ice Sheet is underlain by subglacial sediments ~3 km thick and that these are influencing the flow regime of the overlying ice. We show that subglacial sediments are important in modulating ice dynamics, not just for the West Antarctic Ice Sheet, but also for its much larger neighbor, and suggest that the sedimentary basin identified here may contain information on the Neogene glacial history of this part of the East Antarctic Ice Sheet. Keywords: East Antarctica, marine sediments, magnetics, subglacial geology.

Published
2006

26. Diverse landscapes beneath Pine Island Glacier influence ice flow

Author

Bingham, Robert G., Vaughan, David G., King, Edward C., Davies, Damon, Cornford, Stephen L., Smith, Andrew M., Arthern, Robert J., Brisbourne, Alex M., De Rydt, Jan, Graham, Alastair G. C., Spagnolo, Matteo, Marsh, Oliver J., and Shean, David E.

Subjects
Science, lcsh:Q, lcsh:Science, Article
Abstract

The retreating Pine Island Glacier (PIG), West Antarctica, presently contributes ~5–10% of global sea-level rise. PIG’s retreat rate has increased in recent decades with associated thinning migrating upstream into tributaries feeding the main glacier trunk. To project future change requires modelling that includes robust parameterisation of basal traction, the resistance to ice flow at the bed. However, most ice-sheet models estimate basal traction from satellite-derived surface velocity, without a priori knowledge of the key processes from which it is derived, namely friction at the ice-bed interface and form drag, and the resistance to ice flow that arises as ice deforms to negotiate bed topography. Here, we present high-resolution maps, acquired using ice-penetrating radar, of the bed topography across parts of PIG. Contrary to lower-resolution data currently used for ice-sheet models, these data show a contrasting topography across the ice-bed interface. We show that these diverse subglacial landscapes have an impact on ice flow, and present a challenge for modelling ice-sheet evolution and projecting global sea-level rise from ice-sheet loss., Projecting the future retreat and thus global sea level contributions of Antarctica’s Pine Island Glacier is hampered by a poor grasp of what controls flow at the ice base. Here, via high-resolution ice-radar imaging, the authors show diverse landscapes beneath the glacier fundamentally influence ice flow.

Published
2017

27. Subglacial lakes and hydrology across the Ellsworth Subglacial Highlands, West Antarctica

Author

Napoleoni, Felipe, primary, Jamieson, Stewart S. R., additional, Ross, Neil, additional, Bentley, Michael J., additional, Rivera, Andrés, additional, Smith, Andrew M., additional, Siegert, Martin J., additional, Paxman, Guy J. G., additional, Gacitúa, Guisella, additional, Uribe, José A., additional, Zamora, Rodrigo, additional, Brisbourne, Alex M., additional, and Vaughan, David G., additional

Published
2020
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31. Contributors

Author

Tuckett, Richard P., primary, Cohen, Shabtai, additional, Dorman, Lev I., additional, Stenchikov, Georgiy, additional, Lourens, Lucas J., additional, Tuenter, Erik, additional, Zalasiewicz, Jan, additional, Williams, Mark, additional, Reichler, Thomas, additional, Trigo, Ricardo M., additional, Gimeno, Luis, additional, Fiedler, Wolfgang, additional, Humphries, Murray M., additional, Pelini, Shannon L., additional, Prior, Kirsten M., additional, Parker, Derrick J., additional, Dzurisin, Jason D.K., additional, Hellmann, Jessica J., additional, Lindroth, Richard L., additional, Edwards, Martin, additional, Attrill, Martin J., additional, Worm, Boris, additional, Lotze, Heike K., additional, Mieszkowska, Nova, additional, Morecroft, Michael D., additional, Keith, Sally A., additional, Dixon, Geoffrey R., additional, Gehrels, Roland, additional, Kanzow, T., additional, Visbeck, M., additional, Turley, Carol, additional, Findlay, Helen S., additional, Vaughan, David G., additional, Aptroot, Andre, additional, Nicholls, Robert J., additional, Woodroffe, Colin, additional, Burkett, Virginia, additional, Garrett, Karen A., additional, Nita, M., additional, Wolf, E.D. De, additional, Gomez, L., additional, and Sparks, A.H., additional

Published
2009
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32. Supplementary material to "Subglacial lakes and hydrology across the Ellsworth Subglacial Highlands, West Antarctica"

Author

Napoleoni, Felipe, primary, Jamieson, Stewart S.R., additional, Ross, Neil, additional, Bentley, Michael J., additional, Rivera, Andrés, additional, Smith, Andrew M., additional, Siegert, Martin J., additional, Paxman, Guy J. G., additional, Gacitúa, Guisella, additional, Uribe, José A., additional, Zamora, Rodrigo, additional, Brisbourne, Alex M., additional, and Vaughan, David G., additional

Published
2020
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34. Distortion of isochronous layers in ice revealed by ground-penetrating radar

Author

Vaughan, David G., Corr, Hugh F.J., Doake, Christopher S.M., and Waddington, Ed. D.

Subjects
Ground penetrating radar -- Usage, Ice -- Research, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Ground-penetrating radar is used to delineate reflections in ice sheets. Ground-penetrating radar data from Fletcher Promontory, Antartica shows arches and troughs in isochronous ice layers to a depth of 100 m. Their origin can be determined by their growth with depth, and one arch seems to be due to a local anomaly in vertical spin-rate. This feature is an indication of the nonlinear rheology of ice.

Published
1999

35. Variability of Basal Melt Beneath the Pine Island Glacier Ice Shelf, West Antarctica

Author

Bindschadler, Robert, Vaughan, David G, and Vornberger, Patricia

Subjects
Geophysics
Abstract

Observations from satellite and airborne platforms are combined with model calculations to infer the nature and efficiency of basal melting of the Pine Island Glacier ice shelf, West Antarctica, by ocean waters. Satellite imagery shows surface features that suggest ice-shelf-wide changes to the ocean s influence on the ice shelf as the grounding line retreated. Longitudinal profiles of ice surface and bottom elevations are analyzed to reveal a spatially dependent pattern of basal melt with an annual melt flux of 40.5 Gt/a. One profile captures a persistent set of surface waves that correlates with quasi-annual variations of atmospheric forcing of Amundsen Sea circulation patterns, establishing a direct connection between atmospheric variability and sub-ice-shelf melting. Ice surface troughs are hydrostatically compensated by ice-bottom voids up to 150m deep. Voids form dynamically at the grounding line, triggered by enhanced melting when warmer-than-average water arrives. Subsequent enlargement of the voids is thermally inefficient (4% or less) compared with an overall melting efficiency beneath the ice shelf of 22%. Residual warm water is believed to cause three persistent polynyas at the ice-shelf front seen in Landsat imagery. Landsat thermal imagery confirms the occurrence of warm water at the same locations.

Published
2011
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36. Sustained Antarctic Research: A 21st Century Imperative

Author

Kennicutt, Mahlon C., primary, Bromwich, David, additional, Liggett, Daniela, additional, Njåstad, Birgit, additional, Peck, Lloyd, additional, Rintoul, Stephen R., additional, Ritz, Catherine, additional, Siegert, Martin J., additional, Aitken, Alan, additional, Brooks, Cassandra M., additional, Cassano, John, additional, Chaturvedi, Sanjay, additional, Chen, Dake, additional, Dodds, Klaus, additional, Golledge, Nicholas R., additional, Le Bohec, Céline, additional, Leppe, Marcelo, additional, Murray, Alison, additional, Nath, P. Chandrika, additional, Raphael, Marilyn N., additional, Rogan-Finnemore, Michelle, additional, Schroeder, Dustin M., additional, Talley, Lynne, additional, Travouillon, Tony, additional, Vaughan, David G., additional, Wang, Lifan, additional, Weatherwax, Allan T., additional, Yang, Huigen, additional, and Chown, Steven L., additional

Published
2019
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41. How dynamic are ice-stream beds?

Author

Davies, Damon, primary, Bingham, Robert G., additional, King, Edward C., additional, Smith, Andrew M., additional, Brisbourne, Alex M., additional, Spagnolo, Matteo, additional, Graham, Alastair G. C., additional, Hogg, Anna E., additional, and Vaughan, David G., additional

Published
2018
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42. Heat Flux Distribution of Antarctica Unveiled

Author

Martos, Yasmina M., primary, Catalán, Manuel, additional, Jordan, Tom A., additional, Golynsky, Alexander, additional, Golynsky, Dmitry, additional, Eagles, Graeme, additional, and Vaughan, David G., additional

Published
2017
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43. How dynamic are ice-stream beds?

Author

Davies, Damon, primary, Bingham, Robert G., additional, King, Edward C., additional, Smith, Andrew M., additional, Brisbourne, Alex M., additional, Spagnolo, Matteo, additional, Graham, Alastair G. C., additional, Hogg, Anna E., additional, and Vaughan, David G., additional

Published
2017
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44. Observations: Cryosphere

Author

Vaughan, David G, Comiso, Josefino, Allison, Ian, Carrasco, Jorge, Kaser, Georg, Kwok, Ronald, Mote, Philip, Murray, Tavi, Paul, Frank, Ren, Jiawen, Rignot, Eric, Solomina, Olga, Steffen, Konrad, Zhang, Tingjun, University of Zurich, Stocker, Thomas F, Qin, Dahe, Plattner, Gian-Kasper, Tignor, Melinda M B, Allen, Simon K, Boschung, Judith, Nauels, Alexander, Xia, Yu, Bex, Vincent, and Midgley, Pauline M

Subjects
10122 Institute of Geography, 910 Geography & travel
Published
2014

45. Sea-bed corrugations beneath an Antarctic ice shelf revealed by autonomous underwater vehicle survey: Origin and implications for the history of Pine Island Glacier

Author

Graham, Alastair, Dutrieux, Pierre, Vaughan, David G., Nitsche, Frank O., Gyllencreutz, Richard, Greenwood, Sarah L., Larter, Robert D., and Jenkins, Adrian

Subjects
Glaciology, F700, F800
Abstract

Ice shelves are critical features in the debate about West Antarctic ice sheet change and sea level rise, both because they limit ice discharge and because they are sensitive to change in the surrounding ocean. The Pine Island Glacier ice shelf has been thinning rapidly since at least the early 1990s, which has caused its trunk to accelerate and retreat. Although the ice shelf front has remained stable for the past six decades, past periods of ice shelf collapse have been inferred from relict seabed "corrugations" (corrugated ridges), preserved 340 km from the glacier in Pine Island Trough. Here we present high-resolution bathymetry gathered by an autonomous underwater vehicle operating beneath an Antarctic ice shelf, which provides evidence of long-term change in Pine Island Glacier. Corrugations and ploughmarks on a sub-ice shelf ridge that was a former grounding line closely resemble those observed offshore, interpreted previously as the result of iceberg grounding. The same interpretation here would indicate a significantly reduced ice shelf extent within the last 11 kyr, implying Holocene glacier retreat beyond present limits, or a past tidewater glacier regime different from today. The alternative, that corrugations were not formed in open water, would question ice shelf collapse events interpreted from the geological record, revealing detail of another bed-shaping process occurring at glacier margins. We assess hypotheses for corrugation formation and suggest periodic grounding of ice shelf keels during glacier unpinning as a viable origin. This interpretation requires neither loss of the ice shelf nor glacier retreat and is consistent with a "stable" grounding-line configuration throughout the Holocene.

Published
2013

46. Sustained Antarctic Research: A 21stCentury Imperative

Author

Kennicutt, Mahlon C., Bromwich, David, Liggett, Daniela, Njåstad, Birgit, Peck, Lloyd, Rintoul, Stephen R., Ritz, Catherine, Siegert, Martin J., Aitken, Alan, Brooks, Cassandra M., Cassano, John, Chaturvedi, Sanjay, Chen, Dake, Dodds, Klaus, Golledge, Nicholas R., Le Bohec, Céline, Leppe, Marcelo, Murray, Alison, Nath, P. Chandrika, Raphael, Marilyn N., Rogan-Finnemore, Michelle, Schroeder, Dustin M., Talley, Lynne, Travouillon, Tony, Vaughan, David G., Wang, Lifan, Weatherwax, Allan T., Yang, Huigen, and Chown, Steven L.

Abstract

The view from the south is, more than ever, dominated by ominous signs of change. Antarctica and the Southern Ocean are intrinsic to the Earth system, and their evolution is intertwined with and influences the course of the Anthropocene. In turn, changes in the Antarctic affect and presage humanity's future. Growing understanding is countering popular beliefs that Antarctica is pristine, stable, isolated, and reliably frozen. An aspirational roadmap for Antarctic science has facilitated research since 2014. A renewed commitment to gathering further knowledge will quicken the pace of understanding of Earth systems and beyond. Progress is already evident, such as addressing uncertainties in the causes and pace of ice loss and global sea-level rise. However, much remains to be learned. As an iconic global “commons,” the rapidity of Antarctic change will provoke further political action. Antarctic research is more vital than ever to a sustainable future for this One Earth.

Published
2019
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48. Subglacial melt channels and fracture in the floating part of Pine Island Glacier, Antarctica

Author

Vaughan, David G., Corr, Hugh F. J., Bindschadler, Robert A., Dutrieux, Pierre, Gudmundsson, G. Hilmar, Jenkins, Adrian, Newman, Thomas, Vornberger, Patricia, and Wingham, Duncan J.

Subjects
Glaciology
Abstract

A dense grid of ice-penetrating radar sections acquired over Pine Island Glacier, West Antarctica has revealed a network of sinuous subglacial channels, typically 500 m to 3 km wide, and up to 200 m high, in the ice-shelf base. These subglacial channels develop while the ice is floating and result from melting at the base of the ice shelf. Above the apex of most channels, the radar shows isolated reflections from within the ice shelf. Comparison of the radar data with acoustic data obtained using an autonomous submersible, confirms that these echoes arise from open basal crevasses 50–100 m wide aligned with the subglacial channels and penetrating up to 1/3 of the ice thickness. Analogous sets of surface crevasses appear on the ridges between the basal channels. We suggest that both sets of crevasses were formed during the melting of the subglacial channels as a response to vertical flexing of the ice shelf toward the hydrostatic condition. Finite element modeling of stresses produced after the formation of idealized basal channels indicates that the stresses generated have the correct pattern and, if the channels were formed sufficiently rapidly, would have sufficient magnitude to explain the formation of the observed basal and surface crevasse sets. We conclude that ice-shelf basal melting plays a role in determining patterns of surface and basal crevassing. Increased delivery of warm ocean water into the sub-ice shelf cavity may therefore cause not only thinning but also structural weakening of the ice shelf, perhaps, as a prelude to eventual collapse.

Published
2012
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49. Multi-decadal glacier surface lowering in the Antarctic Peninsula

Author

Kunz, Matthias, King, Matt A., Mills, Jon P., Miller, Pauline E., Fox, Adrian J., Vaughan, David G., and Marsh, Stuart H.

Subjects
Glaciology
Abstract

From approximately 400 glaciers of the western Antarctic Peninsula, no in situ records of mass balance exist and their recent contribution to sea level is consequently poorly constrained. We seek to address this shortcoming by using surface elevations from USGS and BAS airborne(1948–2005) and ASTER spaceborne (2001–2010) stereo imagery, combined by using a rigorous semi-automated registration approach, to determine multi-decadal glacier surface elevation changes in the western Antarctic Peninsula for 12 glaciers. All observed glaciers show near-frontal surface lowering and an annual mean lowering rate of 0.28 � 0.03 m/yr at the lower portion of the glaciers during the �4 decades following the mid-1960s, with higher rates for the glaciers in the north-west parts of the Antarctic Peninsula. Increased lowering of up to 0.6 m/yr can be observed since the 1990s, in close correspondence to increased atmospheric positive degree days. In all cases, surface lowering reduces to zero within 5 km of the glacier front at around 400 m altitude. This lowering may have been at least partially compensated for by increased highaltitude accumulation.

Published
2012
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50. Investigating Greenland Ice Sheet dynamics using high resolution full-Stokes simulations

Author

Gillet-Chaulet, Fabien, Gagliardini, Olivier, Ritz, Catherine, Durand, Gaël, Nodet, Maëlle, Zwinger, Thomas, Greve, Ralph, Seddik, Hakime, Vaughan, David G., Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Modelling, Observations, Identification for Environmental Sciences (MOISE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Kuntzmann (LJK), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Scientific Computing Ltd (CSC), Institute of Low Temperature Science [Sapporo], Hokkaido University [Sapporo, Japan], British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut National Polytechnique de Grenoble (INPG), Institute of Low Temperature Science, Hokkaido University, and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2011

Catalog

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