Articles | Volume 5, issue 2
https://doi.org/10.5194/tc-5-329-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/tc-5-329-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
13 Apr 2011
Research article |
| 13 Apr 2011
Imaging the structure of cave ice by ground-penetrating radar
H. Hausmann
Institute of Geodesy and Geophysics, Vienna University of Technology, Austria
M. Behm
Institute of Geodesy and Geophysics, Vienna University of Technology, Austria
Related subject area
Ice Physics
Broadband spectral induced polarization for the detection of Permafrost and an approach to ice content estimation – a case study from Yakutia, Russia
Ice fabrics in two-dimensional flows: beyond pure and simple shear
Ultrasonic and seismic constraints on crystallographic preferred orientations of the Priestley Glacier shear margin, Antarctica
Modeling enhanced firn densification due to strain softening
Polarimetric radar reveals the spatial distribution of ice fabric at domes and divides in East Antarctica
Thermal structure of the Amery Ice Shelf from borehole observations and simulations
A probabilistic model for fracture events of Petermann ice islands under the influence of atmospheric and oceanic conditions
Sea ice thickness from air-coupled flexural waves
Geothermal heat flux from measured temperature profiles in deep ice boreholes in Antarctica
Sensitivity of ice loss to uncertainty in flow law parameters in an idealized one-dimensional geometry
Strain response and energy dissipation of floating saline ice under cyclic compressive stress
Observation of an optical anisotropy in the deep glacial ice at the geographic South Pole using a laser dust logger
Using a composite flow law to model deformation in the NEEM deep ice core, Greenland – Part 1: The role of grain size and grain size distribution on deformation of the upper 2207 m
Using a composite flow law to model deformation in the NEEM deep ice core, Greenland – Part 2: The role of grain size and premelting on ice deformation at high homologous temperature
Laboratory study of the properties of frazil ice particles and flocs in water of different salinities
The morphology of ice and liquid brine in an environmental scanning electron microscope: a study of the freezing methods
Attenuation of sound in glacier ice from 2 to 35 kHz
Physical and optical characteristics of heavily melted “rotten” Arctic sea ice
Crystallographic preferred orientations of ice deformed in direct-shear experiments at low temperatures
The role of subtemperate slip in thermally driven ice stream margin migration
Deriving micro- to macro-scale seismic velocities from ice-core c axis orientations
From cyclic ice streaming to Heinrich-like events: the grow-and-surge instability in the Parallel Ice Sheet Model
Could promontories have restricted sea-glacier penetration into marine embayments during Snowball Earth events?
Models for polythermal ice sheets and glaciers
Monitoring the temperature-dependent elastic and anelastic properties in isotropic polycrystalline ice using resonant ultrasound spectroscopy
Interaction of marine ice-sheet instabilities in two drainage basins: simple scaling of geometry and transition time
Radio-frequency probes of Antarctic ice at South Pole
Data assimilation using a hybrid ice flow model
Jan Mudler, Andreas Hördt, Dennis Kreith, Madhuri Sugand, Kirill Bazhin, Lyudmila Lebedeva, and Tino Radić
The Cryosphere, 16, 4727–4744, https://doi.org/10.5194/tc-16-4727-2022, https://doi.org/10.5194/tc-16-4727-2022, 2022
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The spectral electrical signal of ice exhibits a strong characteristic behaviour in the frequency range from 100 Hz to 100 kHz, due to polarization effects. With our geophysical method, we can analyse this characteristic to detect subsurface ice. Moreover, we use a model to quantify 2-D ground ice content based on our data. The potential of our new measurement device is showed up. Data were taken on a permafrost site in Yakutia, and the results are in agreement with other existing field data.
Daniel H. Richards, Samuel S. Pegler, and Sandra Piazolo
The Cryosphere, 16, 4571–4592, https://doi.org/10.5194/tc-16-4571-2022, https://doi.org/10.5194/tc-16-4571-2022, 2022
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Understanding the orientation of ice grains is key for predicting ice flow. We explore the evolution of these orientations using a new efficient model. We present an exploration of the patterns produced under a range of temperatures and 2D deformations, including for the first time a universal regime diagram. We do this for deformations relevant to ice sheets but not studied in experiments. These results can be used to understand drilled ice cores and improve future modelling of ice sheets.
Franz Lutz, David J. Prior, Holly Still, M. Hamish Bowman, Bia Boucinhas, Lisa Craw, Sheng Fan, Daeyeong Kim, Robert Mulvaney, Rilee E. Thomas, and Christina L. Hulbe
The Cryosphere, 16, 3313–3329, https://doi.org/10.5194/tc-16-3313-2022, https://doi.org/10.5194/tc-16-3313-2022, 2022
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Ice crystal alignment in the sheared margins of fast-flowing polar ice is important as it may control the ice sheet flow rate, from land to the ocean. Sampling shear margins is difficult because of logistical and safety considerations. We show that crystal alignments in a glacier shear margin in Antarctica can be measured using sound waves. Results from a seismic experiment on the 50 m scale and from ultrasonic experiments on the decimetre scale match ice crystal measurements from an ice core.
Falk M. Oraschewski and Aslak Grinsted
The Cryosphere, 16, 2683–2700, https://doi.org/10.5194/tc-16-2683-2022, https://doi.org/10.5194/tc-16-2683-2022, 2022
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Old snow (denoted as firn) accumulates in the interior of ice sheets and gets densified into glacial ice. Typically, this densification is assumed to only depend on temperature and accumulation rate. However, it has been observed that stretching of the firn by horizontal flow also enhances this process. Here, we show how to include this effect in classical firn models. With the model we confirm that softening of the firn controls firn densification in areas with strong horizontal stretching.
M. Reza Ershadi, Reinhard Drews, Carlos Martín, Olaf Eisen, Catherine Ritz, Hugh Corr, Julia Christmann, Ole Zeising, Angelika Humbert, and Robert Mulvaney
The Cryosphere, 16, 1719–1739, https://doi.org/10.5194/tc-16-1719-2022, https://doi.org/10.5194/tc-16-1719-2022, 2022
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Radio waves transmitted through ice split up and inform us about the ice sheet interior and orientation of single ice crystals. This can be used to infer how ice flows and improve projections on how it will evolve in the future. Here we used an inverse approach and developed a new algorithm to infer ice properties from observed radar data. We applied this technique to the radar data obtained at two EPICA drilling sites, where ice cores were used to validate our results.
Yu Wang, Chen Zhao, Rupert Gladstone, Ben Galton-Fenzi, and Roland Warner
The Cryosphere, 16, 1221–1245, https://doi.org/10.5194/tc-16-1221-2022, https://doi.org/10.5194/tc-16-1221-2022, 2022
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The thermal structure of the Amery Ice Shelf and its spatial pattern are evaluated and analysed through temperature observations from six boreholes and numerical simulations. The simulations demonstrate significant ice warming downstream along the ice flow and a great variation of the thermal structure across the ice flow. We suggest that the thermal structure of the Amery Ice Shelf is unlikely to be affected by current climate changes on decadal timescales.
Reza Zeinali-Torbati, Ian D. Turnbull, Rocky S. Taylor, and Derek Mueller
The Cryosphere, 15, 5601–5621, https://doi.org/10.5194/tc-15-5601-2021, https://doi.org/10.5194/tc-15-5601-2021, 2021
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Using the reanalysis datasets and the Canadian Ice Island Drift, Deterioration and Detection database, a probabilistic model was developed to quantify ice island fracture probability under various atmospheric and oceanic conditions. The model identified water temperature as the most dominant variable behind ice island fracture events, while ocean currents played a minor role. The developed model offers a predictive capability and could be of particular interest to offshore and marine activities.
Rowan Romeyn, Alfred Hanssen, Bent Ole Ruud, and Tor Arne Johansen
The Cryosphere, 15, 2939–2955, https://doi.org/10.5194/tc-15-2939-2021, https://doi.org/10.5194/tc-15-2939-2021, 2021
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Air-coupled flexural waves are produced by the interaction between pressure waves in air and bending waves in a floating ice sheet. The frequency of these waves is related to the physical properties of the ice sheet, specifically its thickness and rigidity. We demonstrate the usefulness of air-coupled flexural waves for estimating ice thickness and give a theoretical description of the governing physics that highlights their similarity to related phenomena in other fields.
Pavel Talalay, Yazhou Li, Laurent Augustin, Gary D. Clow, Jialin Hong, Eric Lefebvre, Alexey Markov, Hideaki Motoyama, and Catherine Ritz
The Cryosphere, 14, 4021–4037, https://doi.org/10.5194/tc-14-4021-2020, https://doi.org/10.5194/tc-14-4021-2020, 2020
Maria Zeitz, Anders Levermann, and Ricarda Winkelmann
The Cryosphere, 14, 3537–3550, https://doi.org/10.5194/tc-14-3537-2020, https://doi.org/10.5194/tc-14-3537-2020, 2020
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The flow of ice drives mass losses in the large ice sheets. Sea-level rise projections rely on ice-sheet models, solving the physics of ice flow and melt. Unfortunately the parameters in the physics of flow are uncertain. Here we show, in an idealized setup, that these uncertainties can double flow-driven mass losses within the possible range of parameters. It is possible that this uncertainty carries over to realistic sea-level rise projections.
Mingdong Wei, Arttu Polojärvi, David M. Cole, and Malith Prasanna
The Cryosphere, 14, 2849–2867, https://doi.org/10.5194/tc-14-2849-2020, https://doi.org/10.5194/tc-14-2849-2020, 2020
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Laboratory-scale work on saline ice is usually limited to the use of dry isothermal specimens. Here we developed techniques for conducting floating-ice experiments. The mechanical behavior of floating-ice specimens under cyclic compression was compared with that of dry specimens. Moreover, both of them were successfully analyzed using a theoretical model. Results demonstrate the importance of the work on warm and floating ice, increasingly existing in the polar regions due to climate change.
Martin Rongen, Ryan Carlton Bay, and Summer Blot
The Cryosphere, 14, 2537–2543, https://doi.org/10.5194/tc-14-2537-2020, https://doi.org/10.5194/tc-14-2537-2020, 2020
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We report on the observation of a directional anisotropy in the intensity of backscattered light. The measurement was performed using a laser dust logger in the SPC14 drill hole at the geographic South Pole. We find the anisotropy axis to be compatible with the ice flow direction. It is discussed in comparison to a similar anisotropy observed by the IceCube Neutrino Observatory. In future, the measurement principle may provide a continuous record of crystal properties along entire drill holes.
Ernst-Jan N. Kuiper, Ilka Weikusat, Johannes H. P. de Bresser, Daniela Jansen, Gill M. Pennock, and Martyn R. Drury
The Cryosphere, 14, 2429–2448, https://doi.org/10.5194/tc-14-2429-2020, https://doi.org/10.5194/tc-14-2429-2020, 2020
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A composite flow law model applied to crystal size distributions from the NEEM deep ice core predicts that fine-grained layers in ice from the last Glacial period localize deformation as internal shear zones in the Greenland ice sheet deforming by grain-size-sensitive creep. This prediction is consistent with microstructures in Glacial age ice.
Ernst-Jan N. Kuiper, Johannes H. P. de Bresser, Martyn R. Drury, Jan Eichler, Gill M. Pennock, and Ilka Weikusat
The Cryosphere, 14, 2449–2467, https://doi.org/10.5194/tc-14-2449-2020, https://doi.org/10.5194/tc-14-2449-2020, 2020
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Fast ice flow occurs in deeper parts of polar ice sheets, driven by high stress and high temperatures. Above 262 K ice flow is further enhanced, probably by the formation of thin melt layers between ice crystals. A model applying an experimentally derived composite flow law, using temperature and grain size values from the deepest 540 m of the NEEM ice core, predicts that flow in fine-grained layers is enhanced by a factor of 10 compared to coarse-grained layers in the Greenland ice sheet.
Christopher C. Schneck, Tadros R. Ghobrial, and Mark R. Loewen
The Cryosphere, 13, 2751–2769, https://doi.org/10.5194/tc-13-2751-2019, https://doi.org/10.5194/tc-13-2751-2019, 2019
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Properties of suspended frazil ice and flocs in water of different salinities were measured in the lab using high-resolution images. It was found that freshwater frazil particles and flocs were larger than in saline water by ~13 % and 75 %, respectively. Both the growth rate of particles and the porosity of flocs decreased with salinity and ranged between 0.174 and 0.024 mm min−1 and 86 % and 75 % for freshwater and 35 ‰ saline water, respectively.
Ľubica Vetráková, Vilém Neděla, Jiří Runštuk, and Dominik Heger
The Cryosphere, 13, 2385–2405, https://doi.org/10.5194/tc-13-2385-2019, https://doi.org/10.5194/tc-13-2385-2019, 2019
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We froze salty solutions to examine where and how the brine is distributed within the ice by using an environmental scanning electron microscope. The structures are highly heterogeneous, consisting of almost pure ice intertwined with brine, which can form lamellae, veins, or pools on the surface. Considering various concentrations and methods for laboratory ice preparation, we determined how the freezing technique influences the microstructure of the brine on and in the ice.
Alexander Meyer, Dmitry Eliseev, Dirk Heinen, Peter Linder, Franziska Scholz, Lars Steffen Weinstock, Christopher Wiebusch, and Simon Zierke
The Cryosphere, 13, 1381–1394, https://doi.org/10.5194/tc-13-1381-2019, https://doi.org/10.5194/tc-13-1381-2019, 2019
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The acoustic damping in natural glaciers is a largely unexplored physical property that has relevance for various applications particularly for the exploration of glaciers with probes. We present measurements of the attenuation of sound in situ on the Italian glacier Langenferner. The tested frequency ranges from 2 to 35 kHz. The attenuation length ranges between 13 m for low frequencies and 5 m for high frequencies.
Carie M. Frantz, Bonnie Light, Samuel M. Farley, Shelly Carpenter, Ross Lieblappen, Zoe Courville, Mónica V. Orellana, and Karen Junge
The Cryosphere, 13, 775–793, https://doi.org/10.5194/tc-13-775-2019, https://doi.org/10.5194/tc-13-775-2019, 2019
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This paper provides a characterization of the physical and optical properties of "rotten" Arctic sea ice collected in two field seasons from off the coast of Utqiaġvik (formerly Barrow), Alaska. Rotten ice is physically and optically distinct when compared to ice from earlier in the melt season. It is marked by large connected pores, has lost most of its brine content, and scatters more light. This fragile, permeable ice type may become increasingly important in a warming Arctic.
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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Ice deformed in nature develops crystallographic preferred orientations, CPOs, which induce an anisotropy in ice viscosity. Shear experiments of ice revealed a transition in CPO with changing temperature/strain, which is due to the change of dominant CPO-formation mechanism: strain-induced grain boundary migration dominates at higher temperatures and lower strains, while lattice rotation dominates at other conditions. Understanding these mechanisms aids the interpretation of CPOs in natural ice.
Marianne Haseloff, Christian Schoof, and Olivier Gagliardini
The Cryosphere, 12, 2545–2568, https://doi.org/10.5194/tc-12-2545-2018, https://doi.org/10.5194/tc-12-2545-2018, 2018
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The widths of the Siple Coast ice streams evolve on decadal to centennial timescales. We investigate how the rate of thermally driven ice stream widening depends on heat dissipation in the ice stream margin and at the bed, and on the inflow of cold ice from the ice ridge. As determining the migration rate requires resolving heat transfer processes on very small scales, we derive a parametrization of the migration rate in terms of parameters that are available from large-scale model outputs.
Johanna Kerch, Anja Diez, Ilka Weikusat, and Olaf Eisen
The Cryosphere, 12, 1715–1734, https://doi.org/10.5194/tc-12-1715-2018, https://doi.org/10.5194/tc-12-1715-2018, 2018
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We investigate the effect of crystal anisotropy on seismic velocities in glacier ice by calculating seismic phase velocities using the exact c axis angles to describe the crystal orientations in ice-core samples for an alpine and a polar ice core. Our results provide uncertainty estimates for earlier established approximative calculations. Additionally, our findings highlight the variation in seismic velocity at non-vertical incidence as a function of the horizontal azimuth of the seismic plane.
Johannes Feldmann and Anders Levermann
The Cryosphere, 11, 1913–1932, https://doi.org/10.5194/tc-11-1913-2017, https://doi.org/10.5194/tc-11-1913-2017, 2017
Adam J. Campbell, Betzalel Massarano, Edwin D. Waddington, and Stephen G. Warren
The Cryosphere, 11, 1141–1148, https://doi.org/10.5194/tc-11-1141-2017, https://doi.org/10.5194/tc-11-1141-2017, 2017
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How could plant life, that needs light to survive, live on a planet covered with ice? Such a situation is thought to have existed during what are called the Snowball Earth events over 600 million years ago. Here we find that
ice shadows, regions where ice has difficulty flowing into, may have a played a role in that survival of early plant life.
Ian J. Hewitt and Christian Schoof
The Cryosphere, 11, 541–551, https://doi.org/10.5194/tc-11-541-2017, https://doi.org/10.5194/tc-11-541-2017, 2017
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Many glaciers contain ice both below and at the melting temperature. Predicting the evolution of temperature and water content in such ice masses is important because they exert a strong control on the flow of the ice. We present two new models to calculate these quantities, demonstrate a number of example numerical calculations, and compare the results with existing methods. The novelty of the new methods is the inclusion of gravity-driven water transport within the ice.
Matthew J. Vaughan, Kasper van Wijk, David J. Prior, and M. Hamish Bowman
The Cryosphere, 10, 2821–2829, https://doi.org/10.5194/tc-10-2821-2016, https://doi.org/10.5194/tc-10-2821-2016, 2016
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The physical properties of ice are of interest in the study of the dynamics of sea ice, glaciers, and ice sheets. We used resonant ultrasound spectroscopy to estimate the effects of temperature on the elastic and anelastic characteristics of polycrystalline ice, which control the propagation of sound waves. This information helps calibrate seismic data, in order to determine regional-scale ice properties, improving our ability to predict ice sheet behaviour in response to climate change.
J. Feldmann and A. Levermann
The Cryosphere, 9, 631–645, https://doi.org/10.5194/tc-9-631-2015, https://doi.org/10.5194/tc-9-631-2015, 2015
D. Besson and I. Kravchenko
The Cryosphere, 7, 855–866, https://doi.org/10.5194/tc-7-855-2013, https://doi.org/10.5194/tc-7-855-2013, 2013
D. N. Goldberg and O. V. Sergienko
The Cryosphere, 5, 315–327, https://doi.org/10.5194/tc-5-315-2011, https://doi.org/10.5194/tc-5-315-2011, 2011
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