Articles | Volume 19, issue 7
https://doi.org/10.5194/tc-19-2715-2025
© Author(s) 2025. 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-19-2715-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
31 Jul 2025
Research article |
| 31 Jul 2025
| 31 Jul 2025
Numerical study of the error sources in the experimental estimation of thermal diffusivity: an application to debris-covered glaciers
Normandie Université – UNICAEN – UNIROUEN, CNRS, UMR 6143 M2C, Laboratoire Morphodynamique Continentale et Côtière, Caen, France
Department of Atmospheric and Cryospheric Sciences, University of Innsbruck, Innsbruck, Austria
Lindsey Nicholson
Department of Atmospheric and Cryospheric Sciences, University of Innsbruck, Innsbruck, Austria
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Giulia Magnarini, Anya Champagne, Costanza Morino, Calvin Beck, Meven Philippe, Armelle Decaulne, and Susan J. Conway
Earth Surf. Dynam., 12, 657–678, https://doi.org/10.5194/esurf-12-657-2024, https://doi.org/10.5194/esurf-12-657-2024, 2024
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We show that Icelandic long-runout landslides with longitudinal ridges represent good analogues of Martian landforms. The large record of long-runout landslides with longitudinal ridges emplaced after the Last Glacial Maximum in Iceland offers a unique opportunity to study the possible relation between the development of these landforms and environmental conditions. This could have implications for reconstructing Martian paleoclimatic and paleoenvironmental conditions.
Brigitta Goger, Ivana Stiperski, Matthis Ouy, and Lindsey Nicholson
Weather Clim. Dynam., 6, 345–367, https://doi.org/10.5194/wcd-6-345-2025, https://doi.org/10.5194/wcd-6-345-2025, 2025
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We study with numerical simulations whether changing glacier ice surfaces impacts the atmospheric boundary layer structure over a glacier. Under north-westerly flow, a gravity wave forms over the glacier valley. When the surrounding upstream glaciers are removed, the gravity wave is weakened and breaks earlier. This leads to stronger turbulent mixing over the remaining glacier and to higher temperatures. We suggest that glaciers influence each other and should be studied as a connected system.
Giulia Magnarini, Anya Champagne, Costanza Morino, Calvin Beck, Meven Philippe, Armelle Decaulne, and Susan J. Conway
Earth Surf. Dynam., 12, 657–678, https://doi.org/10.5194/esurf-12-657-2024, https://doi.org/10.5194/esurf-12-657-2024, 2024
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We show that Icelandic long-runout landslides with longitudinal ridges represent good analogues of Martian landforms. The large record of long-runout landslides with longitudinal ridges emplaced after the Last Glacial Maximum in Iceland offers a unique opportunity to study the possible relation between the development of these landforms and environmental conditions. This could have implications for reconstructing Martian paleoclimatic and paleoenvironmental conditions.
Adina E. Racoviteanu, Lindsey Nicholson, and Neil F. Glasser
The Cryosphere, 15, 4557–4588, https://doi.org/10.5194/tc-15-4557-2021, https://doi.org/10.5194/tc-15-4557-2021, 2021
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Supraglacial debris cover comprises ponds, exposed ice cliffs, debris material and vegetation. Understanding these features is important for glacier hydrology and related hazards. We use linear spectral unmixing of satellite data to assess the composition of map supraglacial debris across the Himalaya range in 2015. One of the highlights of this study is the automated mapping of supraglacial ponds, which complements and expands the existing supraglacial debris and lake databases.
Rebecca Mott, Ivana Stiperski, and Lindsey Nicholson
The Cryosphere, 14, 4699–4718, https://doi.org/10.5194/tc-14-4699-2020, https://doi.org/10.5194/tc-14-4699-2020, 2020
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The Hintereisferner Experiment (HEFEX) investigated spatial and temporal dynamics of the near-surface boundary layer and associated heat exchange processes close to the glacier surface during the melting season. Turbulence data suggest that strong changes in the local thermodynamic characteristics occur when westerly flows disturbed prevailing katabatic flow, forming across-glacier flows and facilitating warm-air advection from the surrounding ice-free areas, which potentially promote ice melt.
Tobias Zolles, Fabien Maussion, Stephan Peter Galos, Wolfgang Gurgiser, and Lindsey Nicholson
The Cryosphere, 13, 469–489, https://doi.org/10.5194/tc-13-469-2019, https://doi.org/10.5194/tc-13-469-2019, 2019
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A mass and energy balance model was subjected to sensitivity and uncertainty analysis on two different Alpine glaciers. The global sensitivity analysis allowed for a mass balance measurement independent assessment of the model sensitivity and functioned as a reduction of the model free parameter space. A novel approach of a multi-objective optimization estimates the uncertainty of the simulated mass balance and the energy fluxes. The final model uncertainty is up to 1300 kg m−3 per year.
Lindsey I. Nicholson, Michael McCarthy, Hamish D. Pritchard, and Ian Willis
The Cryosphere, 12, 3719–3734, https://doi.org/10.5194/tc-12-3719-2018, https://doi.org/10.5194/tc-12-3719-2018, 2018
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Ground-penetrating radar of supraglacial debris thickness is used to study local thickness variability. Freshly emergent debris cover appears to have higher skewness and kurtosis than more mature debris covers. Accounting for debris thickness variability in ablation models can result in markedly different ice ablation than is calculated using the mean debris thickness. Slope stability modelling reveals likely locations for locally thin debris with high ablation.
Christoph Klug, Erik Bollmann, Stephan Peter Galos, Lindsey Nicholson, Rainer Prinz, Lorenzo Rieg, Rudolf Sailer, Johann Stötter, and Georg Kaser
The Cryosphere, 12, 833–849, https://doi.org/10.5194/tc-12-833-2018, https://doi.org/10.5194/tc-12-833-2018, 2018
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This study presents a reanalysis of the glacier mass balance record at Hintereisferner, Austria, for the period 2001 to 2011. We provide a year-by-year comparison of glaciological and geodetic mass balances obtained from annual airborne laser scanning data. After applying a series of corrections, a comparison of the methods reveals major differences for certain years. We thoroughly discuss the origin of these discrepancies and implications for future glaciological mass balance measurements.
Ulrich Strasser, Thomas Marke, Ludwig Braun, Heidi Escher-Vetter, Irmgard Juen, Michael Kuhn, Fabien Maussion, Christoph Mayer, Lindsey Nicholson, Klaus Niedertscheider, Rudolf Sailer, Johann Stötter, Markus Weber, and Georg Kaser
Earth Syst. Sci. Data, 10, 151–171, https://doi.org/10.5194/essd-10-151-2018, https://doi.org/10.5194/essd-10-151-2018, 2018
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A hydrometeorological and glaciological data set is presented with recordings from several research sites in the Rofental (1891–3772 m a.s.l., Ötztal Alps, Austria). The data sets are spanning 150 years and represent a unique pool of high mountain observations, enabling combined research of atmospheric, cryospheric and hydrological processes in complex terrain, and the development of state-of-the-art hydroclimatological and glacier mass balance models.
Anna Wirbel, Alexander H. Jarosch, and Lindsey Nicholson
The Cryosphere, 12, 189–204, https://doi.org/10.5194/tc-12-189-2018, https://doi.org/10.5194/tc-12-189-2018, 2018
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As debris cover affects the meltwater production and behaviour of glaciers it is important to understand how, and over what timescales, it forms. Here we develop an advanced 3-D numerical model that describes transport of sediment through a glacier to the point where it emerges at the surface. The numerical performance of the model is satisfactory and it reproduces debris structures observed within real-world glaciers, thereby offering a useful tool for future studies of debris-covered glaciers.
Ann V. Rowan, Lindsey Nicholson, Emily Collier, Duncan J. Quincey, Morgan J. Gibson, Patrick Wagnon, David R. Rounce, Sarah S. Thompson, Owen King, C. Scott Watson, Tristram D. L. Irvine-Fynn, and Neil F. Glasser
The Cryosphere Discuss., https://doi.org/10.5194/tc-2017-239, https://doi.org/10.5194/tc-2017-239, 2017
Revised manuscript not accepted
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Many glaciers in the Himalaya are covered with thick layers of rock debris that acts as an insulating blanket and so reduces melting of the underlying ice. Little is known about how melt beneath supraglacial debris varies across glaciers and through the monsoon season. We measured debris temperatures across three glaciers and several years to investigate seasonal trends, and found that sub-debris ice melt can be predicted using a temperature–depth relationship with surface temperature data.
Douglas I. Benn, Sarah Thompson, Jason Gulley, Jordan Mertes, Adrian Luckman, and Lindsey Nicholson
The Cryosphere, 11, 2247–2264, https://doi.org/10.5194/tc-11-2247-2017, https://doi.org/10.5194/tc-11-2247-2017, 2017
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This paper provides the first complete view of the drainage system of a large Himalayan glacier, based on ice-cave exploration and satellite image analysis. Drainage tunnels inside glaciers have a major impact on melting rates, by providing lines of weakness inside the ice and potential pathways for melt-water, and play a key role in the response of debris-covered glaciers to sustained periods of negative mass balance.
Stephan Peter Galos, Christoph Klug, Fabien Maussion, Federico Covi, Lindsey Nicholson, Lorenzo Rieg, Wolfgang Gurgiser, Thomas Mölg, and Georg Kaser
The Cryosphere, 11, 1417–1439, https://doi.org/10.5194/tc-11-1417-2017, https://doi.org/10.5194/tc-11-1417-2017, 2017
Lindsey I. Nicholson, Michał Pętlicki, Ben Partan, and Shelley MacDonell
The Cryosphere, 10, 1897–1913, https://doi.org/10.5194/tc-10-1897-2016, https://doi.org/10.5194/tc-10-1897-2016, 2016
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An Xbox Kinect sensor was used as a close-range surface scanner to produce the first accurate 3D surface models of spikes of snow and ice (known as penitentes) that develop in cold, dry, sunny conditions. The data collected show how penitentes develop over time and how they affect the surface roughness of a glacier. These surface models are useful inputs to modelling studies of how penitentes alter energy exchanges between the atmosphere and the surface and how this affects meltwater production.
R. Prinz, L. I. Nicholson, T. Mölg, W. Gurgiser, and G. Kaser
The Cryosphere, 10, 133–148, https://doi.org/10.5194/tc-10-133-2016, https://doi.org/10.5194/tc-10-133-2016, 2016
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Lewis Glacier has lost > 80 % of its extent since the late 19th century. A sensitivity study using a process-based model assigns this shrinking to decreased atmospheric moisture without increasing air temperatures required. The glacier retreat implies a distinctly different coupling between the glacier's surface-air layer and its surrounding boundary layer, underlining the difficulty of deriving palaeoclimates for larger glacier extents on the basis of modern measurements of small glaciers.
E. Collier, F. Maussion, L. I. Nicholson, T. Mölg, W. W. Immerzeel, and A. B. G. Bush
The Cryosphere, 9, 1617–1632, https://doi.org/10.5194/tc-9-1617-2015, https://doi.org/10.5194/tc-9-1617-2015, 2015
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We investigate the impact of surface debris on glacier energy and mass fluxes and on atmosphere-glacier feedbacks in the Karakoram range, by including debris in an interactively coupled atmosphere-glacier model. The model is run from 1 May to 1 October 2004, with a simple specification of debris thickness. We find an appreciable reduction in ablation that exceeds 5m w.e. on glacier tongues, as well as significant alterations to near-surface air temperatures and boundary layer dynamics.
E. Collier, L. I. Nicholson, B. W. Brock, F. Maussion, R. Essery, and A. B. G. Bush
The Cryosphere, 8, 1429–1444, https://doi.org/10.5194/tc-8-1429-2014, https://doi.org/10.5194/tc-8-1429-2014, 2014
W. Gurgiser, B. Marzeion, L. Nicholson, M. Ortner, and G. Kaser
The Cryosphere, 7, 1787–1802, https://doi.org/10.5194/tc-7-1787-2013, https://doi.org/10.5194/tc-7-1787-2013, 2013
S. MacDonell, C. Kinnard, T. Mölg, L. Nicholson, and J. Abermann
The Cryosphere, 7, 1513–1526, https://doi.org/10.5194/tc-7-1513-2013, https://doi.org/10.5194/tc-7-1513-2013, 2013
L. I. Nicholson, R. Prinz, T. Mölg, and G. Kaser
The Cryosphere, 7, 1205–1225, https://doi.org/10.5194/tc-7-1205-2013, https://doi.org/10.5194/tc-7-1205-2013, 2013
Related subject area
Discipline: Glaciers | Subject: Instrumentation
Layer-optimized synthetic aperture radar processing with a mobile phase-sensitive radar: a proof of concept for detecting the deep englacial stratigraphy of Colle Gnifetti, Switzerland and Italy
Brief communication: A technique for making in situ measurements at the ice–water boundary of small pieces of floating glacier ice
Spatial characterization of near-surface structure and meltwater runoff conditions across the Devon Ice Cap from dual-frequency radar reflectivity
Topology and spatial-pressure-distribution reconstruction of an englacial channel
Pressure and inertia sensing drifters for glacial hydrology flow path measurements
Falk M. Oraschewski, Inka Koch, M. Reza Ershadi, Jonathan D. Hawkins, Olaf Eisen, and Reinhard Drews
The Cryosphere, 18, 3875–3889, https://doi.org/10.5194/tc-18-3875-2024, https://doi.org/10.5194/tc-18-3875-2024, 2024
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Mountain glaciers have a layered structure which contains information about past snow accumulation and ice flow. Using ground-penetrating radar instruments, the internal structure can be observed. The detection of layers in the deeper parts of a glacier is often difficult. Here, we present a new approach for imaging the englacial structure of an Alpine glacier (Colle Gnifetti, Switzerland and Italy) using a phase-sensitive radar that can detect reflection depth changes at sub-wavelength scales.
Hayden A. Johnson, Oskar Glowacki, Grant B. Deane, and M. Dale Stokes
The Cryosphere, 18, 265–272, https://doi.org/10.5194/tc-18-265-2024, https://doi.org/10.5194/tc-18-265-2024, 2024
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This paper is about a way to make measurements close to small pieces of floating glacier ice. This is done by attaching instruments to the ice from a small boat. Making these measurements will be helpful for the study of the physics that goes on at small scales when glacier ice is in contact with ocean water. Understanding these small-scale physics may ultimately help improve our understanding of how much ice in Greenland and Antarctica will melt as a result of warming oceans.
Kristian Chan, Cyril Grima, Anja Rutishauser, Duncan A. Young, Riley Culberg, and Donald D. Blankenship
The Cryosphere, 17, 1839–1852, https://doi.org/10.5194/tc-17-1839-2023, https://doi.org/10.5194/tc-17-1839-2023, 2023
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Climate warming has led to more surface meltwater produced on glaciers that can refreeze in firn to form ice layers. Our work evaluates the use of dual-frequency ice-penetrating radar to characterize these ice layers on the Devon Ice Cap. Results indicate that they are meters thick and widespread, and thus capable of supporting lateral meltwater runoff from the top of ice layers. We find that some of this meltwater runoff could be routed through supraglacial rivers in the ablation zone.
Laura Piho, Andreas Alexander, and Maarja Kruusmaa
The Cryosphere, 16, 3669–3683, https://doi.org/10.5194/tc-16-3669-2022, https://doi.org/10.5194/tc-16-3669-2022, 2022
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In this study we develop a novel method to map subsurface water flow paths and spatially reference in situ data from such environments. We demonstrate the feasibility of our method with the reconstruction of the flow path of an englacial channel and the water pressures therein. Our method opens up for direct mapping of subsurface water flow paths, not only in glacier hydrology but also in other applications (e.g., karst caves, pipelines, sewer systems).
Andreas Alexander, Maarja Kruusmaa, Jeffrey A. Tuhtan, Andrew J. Hodson, Thomas V. Schuler, and Andreas Kääb
The Cryosphere, 14, 1009–1023, https://doi.org/10.5194/tc-14-1009-2020, https://doi.org/10.5194/tc-14-1009-2020, 2020
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This work shows the potential of pressure and inertia sensing drifters to measure flow parameters along glacial channels. The technology allows us to record the spatial distribution of water pressures, as well as an estimation of the flow velocity along the flow path in the channels. The measurements show a high repeatability and the potential to identify channel morphology from sensor readings.
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Short summary
A glacier's debris cover strongly modifies its mass balance in contrast to a clean-ice glacier. A key parameter for calculating sub-debris melt is the thermal diffusivity of the debris layer. Conway and Rasmussen (2000) present a method to estimate this value based on simple heat diffusion principles. Our analysis shows that the selected temporal and spatial sampling intervals affect the estimated value of thermal diffusivity, resulting in glacier melt being systematically underestimated.
A glacier's debris cover strongly modifies its mass balance in contrast to a clean-ice glacier....
