Articles | Volume 15, issue 5
https://doi.org/10.5194/tc-15-2235-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-15-2235-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 May 2021
Research article |
| 10 May 2021
| 10 May 2021
The temperature change shortcut: effects of mid-experiment temperature changes on the deformation of polycrystalline ice
Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia
Adam Treverrow
Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia
Sheng Fan
Department of Geology, University of Otago, Dunedin, New Zealand
Mark Peternell
Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
Australian Antarctic Program Partnership, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia
Felicity McCormack
School of Earth, Atmosphere & Environment, Monash University, Melbourne, VIC, Australia
Jason Roberts
Australian Antarctic Program Partnership, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia
Australian Antarctic Division, Hobart, TAS, Australia
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Sheng Fan, Travis F. Hager, David J. Prior, Andrew J. Cross, David L. Goldsby, Chao Qi, Marianne Negrini, and John Wheeler
The Cryosphere, 14, 3875–3905, https://doi.org/10.5194/tc-14-3875-2020, https://doi.org/10.5194/tc-14-3875-2020, 2020
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We performed uniaxial compression experiments on synthetic ice samples. We report ice microstructural evolution at –20 and –30 °C that has never been reported before. Microstructural data show the opening angle of c-axis cones decreases with increasing strain or with decreasing temperature, suggesting a more active grain rotation. CPO intensity weakens with temperature because CPO of small grains is weaker, and it can be explained by grain boundary sliding or nucleation with random orientations.
Syed Abdul Salam, Jason L. Roberts, Felicity S. McCormack, Richard Coleman, and Jacqueline A. Halpin
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2020-146, https://doi.org/10.5194/essd-2020-146, 2020
Publication in ESSD not foreseen
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Accurate estimates of englacial temperature and geothermal heat flux are incredibly important
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Chao Qi, David J. Prior, Lisa Craw, Sheng Fan, Maria-Gema Llorens, Albert Griera, Marianne Negrini, Paul D. Bons, and David L. Goldsby
The Cryosphere, 13, 351–371, https://doi.org/10.5194/tc-13-351-2019, https://doi.org/10.5194/tc-13-351-2019, 2019
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Sue Cook, Benjamin K. Galton-Fenzi, Stefan R. M. Ligtenberg, and Richard Coleman
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Sue Cook, Jan Åström, Thomas Zwinger, Benjamin Keith Galton-Fenzi, Jamin Stevens Greenbaum, and Richard Coleman
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Marie G. P. Cavitte, Frédéric Parrenin, Catherine Ritz, Duncan A. Young, Brice Van Liefferinge, Donald D. Blankenship, Massimo Frezzotti, and Jason L. Roberts
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Jason Roberts, Andrew Moy, Christopher Plummer, Tas van Ommen, Mark Curran, Tessa Vance, Samuel Poynter, Yaping Liu, Joel Pedro, Adam Treverrow, Carly Tozer, Lenneke Jong, Pippa Whitehouse, Laetitia Loulergue, Jerome Chappellaz, Vin Morgan, Renato Spahni, Adrian Schilt, Cecilia MacFarling Meure, David Etheridge, and Thomas Stocker
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Preprint withdrawn
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Here we present a revised Law Dome, Dome Summit South (DSS) ice core age model (denoted LD2017) that significantly improves the chronology over the last 88 thousand years. An ensemble approach was used, allowing for the computation of both a median age and associated uncertainty as a function of depth. We use a non-linear interpolation between age ties and unlike previous studies, we made an independent estimate of the snow accumulation rate, where required, for the use of gas based age ties.
Duncan A. Young, Jason L. Roberts, Catherine Ritz, Massimo Frezzotti, Enrica Quartini, Marie G. P. Cavitte, Carly R. Tozer, Daniel Steinhage, Stefano Urbini, Hugh F. J. Corr, Tas van Ommen, and Donald D. Blankenship
The Cryosphere, 11, 1897–1911, https://doi.org/10.5194/tc-11-1897-2017, https://doi.org/10.5194/tc-11-1897-2017, 2017
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To find records of the greenhouse gases found in key periods of climate transition, we need to find sites of unmelted old ice at the base of the Antarctic ice sheet for ice core retrieval. A joint US–Australian–EU team performed a high-resolution survey of such a site (1 km line spacing) near Concordia Station in East Antarctica, using airborne ice-penetrating radar. We found promising targets in rough subglacial terrain, surrounded by subglacial lakes restricted below a minimum hydraulic head.
Felicity S. Graham, Jason L. Roberts, Ben K. Galton-Fenzi, Duncan Young, Donald Blankenship, and Martin J. Siegert
Earth Syst. Sci. Data, 9, 267–279, https://doi.org/10.5194/essd-9-267-2017, https://doi.org/10.5194/essd-9-267-2017, 2017
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Antarctic bed topography datasets are interpolated onto low-resolution grids because our observed topography data are sparsely sampled. This has implications for ice-sheet model simulations, especially in regions prone to instability, such as grounding lines, where detailed knowledge of the topography is required. Here, we constructed a high-resolution synthetic bed elevation dataset using observed covariance properties to assess the dependence of simulated ice-sheet dynamics on grid resolution.
Adam Treverrow, Li Jun, and Tim H. Jacka
Earth Syst. Sci. Data, 8, 253–263, https://doi.org/10.5194/essd-8-253-2016, https://doi.org/10.5194/essd-8-253-2016, 2016
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We present ice crystallographic c-axis orientation and grain size data from the Dome Summit South (DSS) ice core drilled 4.7 km SSW of the summit of Law Dome, East Antarctica. These data are from 185 individual thin sections obtained between a depth of 117 m below the surface and the bottom of the DSS core at a depth of 1196 m. Observations of ice microstructures from polar ice cores play a vital role in the development and validation of ice flow relations for numerical ice sheet models.
Carly R. Tozer, Tessa R. Vance, Jason L. Roberts, Anthony S. Kiem, Mark A. J. Curran, and Andrew D. Moy
Hydrol. Earth Syst. Sci., 20, 1703–1717, https://doi.org/10.5194/hess-20-1703-2016, https://doi.org/10.5194/hess-20-1703-2016, 2016
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This study details a systematic approach to finding a new high-resolution East Antarctic ice core site. The study initially outlines seven criteria that a new site must fulfil, encompassing specific accumulation, ice dynamics and atmospheric circulation aspects. We then use numerous techniques including Antarctic surface mass balance syntheses, ground-truthing of satellite data by airborne radar surveys and reanalysis products to pinpoint promising regions.
J. Roberts, C. Plummer, T. Vance, T. van Ommen, A. Moy, S. Poynter, A. Treverrow, M. Curran, and S. George
Clim. Past, 11, 697–707, https://doi.org/10.5194/cp-11-697-2015, https://doi.org/10.5194/cp-11-697-2015, 2015
Short summary
Short summary
The Law Dome, East Antarctica snow accumulation record is extended back to 22 BCE using a power-law vertical strain rate model. The periods of 380-442, 727-783 and 1970-2009 CE show above-average snow accumulation rates, while 663-704, 933-975 and 1429-1468 CE were below average. The calculated snow accumulation rates show good correlation with atmospheric reanalysis estimates and significant spatial correlation over a wide expanse of East Antarctica.
D. E. Gwyther, B. K. Galton-Fenzi, J. R. Hunter, and J. L. Roberts
Ocean Sci., 10, 267–279, https://doi.org/10.5194/os-10-267-2014, https://doi.org/10.5194/os-10-267-2014, 2014
P. Fretwell, H. D. Pritchard, D. G. Vaughan, J. L. Bamber, N. E. Barrand, R. Bell, C. Bianchi, R. G. Bingham, D. D. Blankenship, G. Casassa, G. Catania, D. Callens, H. Conway, A. J. Cook, H. F. J. Corr, D. Damaske, V. Damm, F. Ferraccioli, R. Forsberg, S. Fujita, Y. Gim, P. Gogineni, J. A. Griggs, R. C. A. Hindmarsh, P. Holmlund, J. W. Holt, R. W. Jacobel, A. Jenkins, W. Jokat, T. Jordan, E. C. King, J. Kohler, W. Krabill, M. Riger-Kusk, K. A. Langley, G. Leitchenkov, C. Leuschen, B. P. Luyendyk, K. Matsuoka, J. Mouginot, F. O. Nitsche, Y. Nogi, O. A. Nost, S. V. Popov, E. Rignot, D. M. Rippin, A. Rivera, J. Roberts, N. Ross, M. J. Siegert, A. M. Smith, D. Steinhage, M. Studinger, B. Sun, B. K. Tinto, B. C. Welch, D. Wilson, D. A. Young, C. Xiangbin, and A. Zirizzotti
The Cryosphere, 7, 375–393, https://doi.org/10.5194/tc-7-375-2013, https://doi.org/10.5194/tc-7-375-2013, 2013
J. L. Roberts, A. D. Moy, T. D. van Ommen, M. A. J. Curran, A. P. Worby, I. D. Goodwin, and M. Inoue
The Cryosphere, 7, 263–273, https://doi.org/10.5194/tc-7-263-2013, https://doi.org/10.5194/tc-7-263-2013, 2013
Related subject area
Discipline: Other | Subject: Rheology
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear
Melting and fragmentation laws from the evolution of two large Southern Ocean icebergs estimated from satellite data
Baptiste Journaux, Thomas Chauve, Maurine Montagnat, Andrea Tommasi, Fabrice Barou, David Mainprice, and Léa Gest
The Cryosphere, 13, 1495–1511, https://doi.org/10.5194/tc-13-1495-2019, https://doi.org/10.5194/tc-13-1495-2019, 2019
Short summary
Short summary
Ice mechanics is an important tool to better predict the response of glaciers or polar ice sheets to climate variations.
Nevertheless our current predictive abilities are limited as the microscale mechanisms responsible for ice creep are poorly identified.
We show in this study, using state-of-the-art experimental techniques, which recrystallization processes control ice deformation. This will allow realistic simulations, necessary to predict the long-term effects on ice landmasses.
Nicolas Bouhier, Jean Tournadre, Frédérique Rémy, and Rozenn Gourves-Cousin
The Cryosphere, 12, 2267–2285, https://doi.org/10.5194/tc-12-2267-2018, https://doi.org/10.5194/tc-12-2267-2018, 2018
Short summary
Short summary
The evolution of two large Southern Ocean icebergs, in terms of area and thickness, are used to study the melting and fragmentation laws of icebergs. The area and thickness are estimated by the mean of satellite images and radar altimeter data. Two classical formulations of melting are tested and a fragmentation law depending on the sea temperature and iceberg velocity is proposed and tested. The size distribution of the pieces generated by fragmentation is also estimated.
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Short summary
Ice sheet and ice shelf models rely on data from experiments to accurately represent the way ice moves. Performing experiments at the temperatures and stresses that are generally present in nature takes a long time, and so there are few of these datasets. Here, we test the method of speeding up an experiment by running it initially at a higher temperature, before dropping to a lower target temperature to generate the relevant data. We show that this method can reduce experiment time by 55 %.
Ice sheet and ice shelf models rely on data from experiments to accurately represent the way ice...
