Articles | Volume 13, issue 3
https://doi.org/10.5194/tc-13-795-2019
© Author(s) 2019. 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-13-795-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 Mar 2019
Research article |
| 05 Mar 2019
Extracting recent short-term glacier velocity evolution over southern Alaska and the Yukon from a large collection of Landsat data
Department of Geosciences, University of Oslo, Blindern, 0316 Oslo, Norway
Ted Scambos
National Snow and Ice Data Center (NSIDC), University of Colorado, Boulder, CO 80303, USA
Earth Science and Observation Center (ESOC), University of Colorado, Boulder, CO 80309, USA
Mark Fahnestock
Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
Andreas Kääb
Department of Geosciences, University of Oslo, Blindern, 0316 Oslo, Norway
Related authors
Bas Altena, Andreas Kääb, and Bert Wouters
The Cryosphere, 16, 2285–2300, https://doi.org/10.5194/tc-16-2285-2022, https://doi.org/10.5194/tc-16-2285-2022, 2022
Short summary
Short summary
Repeat overflights of satellites are used to estimate surface displacements. However, such products lack a simple error description for individual measurements, but variation in precision occurs, since the calculation is based on the similarity of texture. Fortunately, variation in precision manifests itself in the correlation peak, which is used for the displacement calculation. This spread is used to make a connection to measurement precision, which can be of great use for model inversion.
Paul Willem Leclercq, Andreas Kääb, and Bas Altena
The Cryosphere, 15, 4901–4907, https://doi.org/10.5194/tc-15-4901-2021, https://doi.org/10.5194/tc-15-4901-2021, 2021
Short summary
Short summary
In this study we present a novel method to detect glacier surge activity. Surges are relevant as they disturb the link between glacier change and climate, and studying surges can also increase understanding of glacier flow. We use variations in Sentinel-1 radar backscatter strength, calculated with the use of Google Earth Engine, to detect surge activity. In our case study for the year 2018–2019 we find 69 cases of surging glaciers globally. Many of these were not previously known to be surging.
Christopher Chambers, Ralf Greve, Bas Altena, and Pierre-Marie Lefeuvre
The Cryosphere, 14, 3747–3759, https://doi.org/10.5194/tc-14-3747-2020, https://doi.org/10.5194/tc-14-3747-2020, 2020
Short summary
Short summary
The topography of the rock below the Greenland ice sheet is not well known. One long valley appears as a line of dips because of incomplete data. So we use ice model simulations that unblock this valley, and these create a watercourse that may represent a form of river over 1000 km long under the ice. When we melt ice at the bottom of the ice sheet only in the deep interior, water can flow down the valley only when the valley is unblocked. It may have developed while an ice sheet was present.
Andreas Kääb, Bas Altena, and Joseph Mascaro
Hydrol. Earth Syst. Sci., 23, 4233–4247, https://doi.org/10.5194/hess-23-4233-2019, https://doi.org/10.5194/hess-23-4233-2019, 2019
Short summary
Short summary
Knowledge of water surface velocities in rivers is useful for understanding a wide range of processes and systems, but is difficult to measure over large reaches. Here, we present a novel method to exploit near-simultaneous imagery produced by the Planet cubesat constellation to track river ice floes and estimate water surface velocities. We demonstrate the method for a 60 km long reach of the Amur River and a 200 km long reach of the Yukon River.
B. Altena, O. N. Haga, C. Nuth, and A. Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-2-W13, 1723–1727, https://doi.org/10.5194/isprs-archives-XLII-2-W13-1723-2019, https://doi.org/10.5194/isprs-archives-XLII-2-W13-1723-2019, 2019
Yongmei Gong, Thomas Zwinger, Jan Åström, Bas Altena, Thomas Schellenberger, Rupert Gladstone, and John C. Moore
The Cryosphere, 12, 1563–1577, https://doi.org/10.5194/tc-12-1563-2018, https://doi.org/10.5194/tc-12-1563-2018, 2018
Short summary
Short summary
In this study we apply a discrete element model capable of simulating ice fracturing. A microscopic-scale discrete process is applied in addition to a continuum ice dynamics model to investigate the mechanisms facilitated by basal meltwater production, surface meltwater and ice crack opening, for the surge in Basin 3, Austfonna ice cap. The discrete element model is used to locate the ice cracks that can penetrate though the full thickness of the glacier and deliver surface water to the bed.
B. Altena, A. Mousivand, J. Mascaro, and A. Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-3-W3, 7–11, https://doi.org/10.5194/isprs-archives-XLII-3-W3-7-2017, https://doi.org/10.5194/isprs-archives-XLII-3-W3-7-2017, 2017
Andreas Kääb, Bas Altena, and Joseph Mascaro
Nat. Hazards Earth Syst. Sci., 17, 627–639, https://doi.org/10.5194/nhess-17-627-2017, https://doi.org/10.5194/nhess-17-627-2017, 2017
Short summary
Short summary
We evaluate for the first time a new class of optical satellite images for measuring Earth surface displacements due to earthquakes – images from cubesats. The PlanetScope cubesats used in this study are 10 cm × 10 cm × 30 cm small and standardized satellites. Around 120 of these cubesats orbit around Earth and are about to provide daily 2–4 m resolution images of the entire land surface of the Earth.
Livia Piermattei, Michael Zemp, Christian Sommer, Fanny Brun, Matthias H. Braun, Liss M. Andreassen, Joaquín M. C. Belart, Etienne Berthier, Atanu Bhattacharya, Laura Boehm Vock, Tobias Bolch, Amaury Dehecq, Inés Dussaillant, Daniel Falaschi, Caitlyn Florentine, Dana Floricioiu, Christian Ginzler, Gregoire Guillet, Romain Hugonnet, Matthias Huss, Andreas Kääb, Owen King, Christoph Klug, Friedrich Knuth, Lukas Krieger, Jeff La Frenierre, Robert McNabb, Christopher McNeil, Rainer Prinz, Louis Sass, Thorsten Seehaus, David Shean, Désirée Treichler, Anja Wendt, and Ruitang Yang
EGUsphere, https://doi.org/10.5194/egusphere-2023-2309, https://doi.org/10.5194/egusphere-2023-2309, 2023
Short summary
Short summary
Satellites have made it possible to observe glacier elevation changes from all around the world. In the present study, we compared the results produced from two different types of satellite data between different research groups and against validation measurements from aeroplanes. We found a large spread between individual results but showed that the group ensemble can be used to reliably estimate glacier elevation changes and related errors from satellite data.
Andreas Kääb and Luc Girod
The Cryosphere, 17, 2533–2541, https://doi.org/10.5194/tc-17-2533-2023, https://doi.org/10.5194/tc-17-2533-2023, 2023
Short summary
Short summary
Following the detachment of the 130 × 106 m3 Sedongpu Glacier (south-eastern Tibet) in 2018, the Sedongpu Valley underwent massive large-volume landscape changes. An enormous volume of in total around 330 × 106 m3 was rapidly eroded, forming a new canyon of up to 300 m depth, 1 km width, and almost 4 km length. Such consequences of glacier change in mountains have so far not been considered at this magnitude and speed.
Naomi E. Ochwat, Ted A. Scambos, Alison F. Banwell, Robert S. Anderson, Michelle L. Maclennan, Ghislain Picard, Julia A. Shates, Sebastian Marinsek, Liliana Margonari, Martin Truffer, and Erin C. Pettit
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-88, https://doi.org/10.5194/tc-2023-88, 2023
Preprint under review for TC
Short summary
Short summary
On the Antarctic Peninsula, there is a small bay that had sea ice fastened to the shoreline ('fast ice') for over a decade. The fast ice stabilized the glaciers that fed into the ocean. In January 2022 this fast ice broke away, using satellite data we found that this was because of low sea ice concentrations and a high long period ocean wave swell. We find that the glaciers have responded to this event by thinning, speeding up, and retreating by breaking off lots of icebergs at remarkable rates.
Sebastian Westermann, Thomas Ingeman-Nielsen, Johanna Scheer, Kristoffer Aalstad, Juditha Aga, Nitin Chaudhary, Bernd Etzelmüller, Simon Filhol, Andreas Kääb, Cas Renette, Louise Steffensen Schmidt, Thomas Vikhamar Schuler, Robin B. Zweigel, Léo Martin, Sarah Morard, Matan Ben-Asher, Michael Angelopoulos, Julia Boike, Brian Groenke, Frederieke Miesner, Jan Nitzbon, Paul Overduin, Simone M. Stuenzi, and Moritz Langer
Geosci. Model Dev., 16, 2607–2647, https://doi.org/10.5194/gmd-16-2607-2023, https://doi.org/10.5194/gmd-16-2607-2023, 2023
Short summary
Short summary
The CryoGrid community model is a new tool for simulating ground temperatures and the water and ice balance in cold regions. It is a modular design, which makes it possible to test different schemes to simulate, for example, permafrost ground in an efficient way. The model contains tools to simulate frozen and unfrozen ground, snow, glaciers, and other massive ice bodies, as well as water bodies.
Inès N. Otosaka, Andrew Shepherd, Erik R. Ivins, Nicole-Jeanne Schlegel, Charles Amory, Michiel R. van den Broeke, Martin Horwath, Ian Joughin, Michalea D. King, Gerhard Krinner, Sophie Nowicki, Anthony J. Payne, Eric Rignot, Ted Scambos, Karen M. Simon, Benjamin E. Smith, Louise S. Sørensen, Isabella Velicogna, Pippa L. Whitehouse, Geruo A, Cécile Agosta, Andreas P. Ahlstrøm, Alejandro Blazquez, William Colgan, Marcus E. Engdahl, Xavier Fettweis, Rene Forsberg, Hubert Gallée, Alex Gardner, Lin Gilbert, Noel Gourmelen, Andreas Groh, Brian C. Gunter, Christopher Harig, Veit Helm, Shfaqat Abbas Khan, Christoph Kittel, Hannes Konrad, Peter L. Langen, Benoit S. Lecavalier, Chia-Chun Liang, Bryant D. Loomis, Malcolm McMillan, Daniele Melini, Sebastian H. Mernild, Ruth Mottram, Jeremie Mouginot, Johan Nilsson, Brice Noël, Mark E. Pattle, William R. Peltier, Nadege Pie, Mònica Roca, Ingo Sasgen, Himanshu V. Save, Ki-Weon Seo, Bernd Scheuchl, Ernst J. O. Schrama, Ludwig Schröder, Sebastian B. Simonsen, Thomas Slater, Giorgio Spada, Tyler C. Sutterley, Bramha Dutt Vishwakarma, Jan Melchior van Wessem, David Wiese, Wouter van der Wal, and Bert Wouters
Earth Syst. Sci. Data, 15, 1597–1616, https://doi.org/10.5194/essd-15-1597-2023, https://doi.org/10.5194/essd-15-1597-2023, 2023
Short summary
Short summary
By measuring changes in the volume, gravitational attraction, and ice flow of Greenland and Antarctica from space, we can monitor their mass gain and loss over time. Here, we present a new record of the Earth’s polar ice sheet mass balance produced by aggregating 50 satellite-based estimates of ice sheet mass change. This new assessment shows that the ice sheets have lost (7.5 x 1012) t of ice between 1992 and 2020, contributing 21 mm to sea level rise.
Juditha Aga, Livia Piermattei, Luc Girod, Kristoffer Aalstad, Trond Eiken, Andreas Kääb, and Sebastian Westermann
EGUsphere, https://doi.org/10.5194/egusphere-2023-321, https://doi.org/10.5194/egusphere-2023-321, 2023
Short summary
Short summary
Coastal rock cliffs on Svalbard are considered to be fairly stable, however, long-term trends of coastal retreat rates are unknown so far. This study presents changes in the coastline along Brøgger Peninsula, Svalbard, based on aerial images from 1970, 1990, 2010 and 2021. Our analysis shows that coastal retreat rates accelerate in the time period 2010–2021, which coincides with increasing storminess, retreating sea ice and increasing ground temperatures.
Michelle L. Maclennan, Jan T. M. Lenaerts, Christine A. Shields, Andrew O. Hoffman, Nander Wever, Megan Thompson-Munson, Andrew C. Winters, Erin C. Pettit, Theodore A. Scambos, and Jonathan D. Wille
The Cryosphere, 17, 865–881, https://doi.org/10.5194/tc-17-865-2023, https://doi.org/10.5194/tc-17-865-2023, 2023
Short summary
Short summary
Atmospheric rivers are air masses that transport large amounts of moisture and heat towards the poles. Here, we use a combination of weather observations and models to quantify the amount of snowfall caused by atmospheric rivers in West Antarctica which is about 10 % of the total snowfall each year. We then examine a unique event that occurred in early February 2020, when three atmospheric rivers made landfall over West Antarctica in rapid succession, leading to heavy snowfall and surface melt.
Fuming Xie, Shiyin Liu, Yongpeng Gao, Yu Zhu, Tobias Bolch, Andreas Kääb, Shimei Duan, Wenfei Miao, Jianfang Kang, Yaonan Zhang, Xiran Pan, Caixia Qin, Kunpeng Wu, Miaomiao Qi, Xianhe Zhang, Ying Yi, Fengze Han, Xiaojun Yao, Qiao Liu, Xin Wang, Zongli Jiang, Donghui Shangguan, Yong Zhang, Richard Grünwald, Muhammad Adnan, Jyoti Karki, and Muhammad Saifullah
Earth Syst. Sci. Data, 15, 847–867, https://doi.org/10.5194/essd-15-847-2023, https://doi.org/10.5194/essd-15-847-2023, 2023
Short summary
Short summary
In this study, first we generated inventories which allowed us to systematically detect glacier change patterns in the Karakoram range. We found that, by the 2020s, there were approximately 10 500 glaciers in the Karakoram mountains covering an area of 22 510.73 km2, of which ~ 10.2 % is covered by debris. During the past 30 years (from 1990 to 2020), the total glacier cover area in Karakoram remained relatively stable, with a slight increase in area of 23.5 km2.
Maximillian Van Wyk de Vries, Shashank Bhushan, Mylène Jacquemart, César Deschamps-Berger, Etienne Berthier, Simon Gascoin, David E. Shean, Dan H. Shugar, and Andreas Kääb
Nat. Hazards Earth Syst. Sci., 22, 3309–3327, https://doi.org/10.5194/nhess-22-3309-2022, https://doi.org/10.5194/nhess-22-3309-2022, 2022
Short summary
Short summary
On 7 February 2021, a large rock–ice avalanche occurred in Chamoli, Indian Himalaya. The resulting debris flow swept down the nearby valley, leaving over 200 people dead or missing. We use a range of satellite datasets to investigate how the collapse area changed prior to collapse. We show that signs of instability were visible as early 5 years prior to collapse. However, it would likely not have been possible to predict the timing of the event from current satellite datasets.
Joseph A. MacGregor, Winnie Chu, William T. Colgan, Mark A. Fahnestock, Denis Felikson, Nanna B. Karlsson, Sophie M. J. Nowicki, and Michael Studinger
The Cryosphere, 16, 3033–3049, https://doi.org/10.5194/tc-16-3033-2022, https://doi.org/10.5194/tc-16-3033-2022, 2022
Short summary
Short summary
Where the bottom of the Greenland Ice Sheet is frozen and where it is thawed is not well known, yet knowing this state is increasingly important to interpret modern changes in ice flow there. We produced a second synthesis of knowledge of the basal thermal state of the ice sheet using airborne and satellite observations and numerical models. About one-third of the ice sheet’s bed is likely thawed; two-fifths is likely frozen; and the remainder is too uncertain to specify.
Frank Paul, Livia Piermattei, Désirée Treichler, Lin Gilbert, Luc Girod, Andreas Kääb, Ludivine Libert, Thomas Nagler, Tazio Strozzi, and Jan Wuite
The Cryosphere, 16, 2505–2526, https://doi.org/10.5194/tc-16-2505-2022, https://doi.org/10.5194/tc-16-2505-2022, 2022
Short summary
Short summary
Glacier surges are widespread in the Karakoram and have been intensely studied using satellite data and DEMs. We use time series of such datasets to study three glacier surges in the same region of the Karakoram. We found strongly contrasting advance rates and flow velocities, maximum velocities of 30 m d−1, and a change in the surge mechanism during a surge. A sensor comparison revealed good agreement, but steep terrain and the two smaller glaciers caused limitations for some of them.
Bas Altena, Andreas Kääb, and Bert Wouters
The Cryosphere, 16, 2285–2300, https://doi.org/10.5194/tc-16-2285-2022, https://doi.org/10.5194/tc-16-2285-2022, 2022
Short summary
Short summary
Repeat overflights of satellites are used to estimate surface displacements. However, such products lack a simple error description for individual measurements, but variation in precision occurs, since the calculation is based on the similarity of texture. Fortunately, variation in precision manifests itself in the correlation peak, which is used for the displacement calculation. This spread is used to make a connection to measurement precision, which can be of great use for model inversion.
Isabelle Gärtner-Roer, Nina Brunner, Reynald Delaloye, Wilfried Haeberli, Andreas Kääb, and Patrick Thee
The Cryosphere, 16, 2083–2101, https://doi.org/10.5194/tc-16-2083-2022, https://doi.org/10.5194/tc-16-2083-2022, 2022
Short summary
Short summary
We intensely investigated the Gruben site in the Swiss Alps, where glaciers and permafrost landforms closely interact, to better understand cold-climate environments. By the interpretation of air photos from 5 decades, we describe long-term developments of the existing landforms. In combination with high-resolution positioning measurements and ground surface temperatures, we were also able to link these to short-term changes and describe different landform responses to climate forcing.
Tazio Strozzi, Andreas Wiesmann, Andreas Kääb, Thomas Schellenberger, and Frank Paul
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-44, https://doi.org/10.5194/essd-2022-44, 2022
Revised manuscript not accepted
Short summary
Short summary
Knowledge on surface velocity of glaciers and ice caps contributes to a better understanding of a wide range of processes related to glacier dynamics, mass change and response to climate. Based on the release of historical satellite radar data from various space agencies we compiled nearly complete mosaics of winter ice surface velocities for the 1990's over the Eastern Arctic. Compared to the present state, we observe a general increase of ice velocities along with a retreat of glacier fronts.
Christian T. Wild, Karen E. Alley, Atsuhiro Muto, Martin Truffer, Ted A. Scambos, and Erin C. Pettit
The Cryosphere, 16, 397–417, https://doi.org/10.5194/tc-16-397-2022, https://doi.org/10.5194/tc-16-397-2022, 2022
Short summary
Short summary
Thwaites Glacier has the potential to significantly raise Antarctica's contribution to global sea-level rise by the end of this century. Here, we use satellite measurements of surface elevation to show that its floating part is close to losing contact with an underwater ridge that currently acts to stabilize. We then use computer models of ice flow to simulate the predicted unpinning, which show that accelerated ice discharge into the ocean follows the breakup of the floating part.
Karen E. Alley, Christian T. Wild, Adrian Luckman, Ted A. Scambos, Martin Truffer, Erin C. Pettit, Atsuhiro Muto, Bruce Wallin, Marin Klinger, Tyler Sutterley, Sarah F. Child, Cyrus Hulen, Jan T. M. Lenaerts, Michelle Maclennan, Eric Keenan, and Devon Dunmire
The Cryosphere, 15, 5187–5203, https://doi.org/10.5194/tc-15-5187-2021, https://doi.org/10.5194/tc-15-5187-2021, 2021
Short summary
Short summary
We present a 20-year, satellite-based record of velocity and thickness change on the Thwaites Eastern Ice Shelf (TEIS), the largest remaining floating extension of Thwaites Glacier (TG). TG holds the single greatest control on sea-level rise over the next few centuries, so it is important to understand changes on the TEIS, which controls much of TG's flow into the ocean. Our results suggest that the TEIS is progressively destabilizing and is likely to disintegrate over the next few decades.
Paul Willem Leclercq, Andreas Kääb, and Bas Altena
The Cryosphere, 15, 4901–4907, https://doi.org/10.5194/tc-15-4901-2021, https://doi.org/10.5194/tc-15-4901-2021, 2021
Short summary
Short summary
In this study we present a novel method to detect glacier surge activity. Surges are relevant as they disturb the link between glacier change and climate, and studying surges can also increase understanding of glacier flow. We use variations in Sentinel-1 radar backscatter strength, calculated with the use of Google Earth Engine, to detect surge activity. In our case study for the year 2018–2019 we find 69 cases of surging glaciers globally. Many of these were not previously known to be surging.
Andreas Kääb, Mylène Jacquemart, Adrien Gilbert, Silvan Leinss, Luc Girod, Christian Huggel, Daniel Falaschi, Felipe Ugalde, Dmitry Petrakov, Sergey Chernomorets, Mikhail Dokukin, Frank Paul, Simon Gascoin, Etienne Berthier, and Jeffrey S. Kargel
The Cryosphere, 15, 1751–1785, https://doi.org/10.5194/tc-15-1751-2021, https://doi.org/10.5194/tc-15-1751-2021, 2021
Short summary
Short summary
Hardly recognized so far, giant catastrophic detachments of glaciers are a rare but great potential for loss of lives and massive damage in mountain regions. Several of the events compiled in our study involve volumes (up to 100 million m3 and more), avalanche speeds (up to 300 km/h), and reaches (tens of kilometres) that are hard to imagine. We show that current climate change is able to enhance associated hazards. For the first time, we elaborate a set of factors that could cause these events.
Andreas Kääb, Tazio Strozzi, Tobias Bolch, Rafael Caduff, Håkon Trefall, Markus Stoffel, and Alexander Kokarev
The Cryosphere, 15, 927–949, https://doi.org/10.5194/tc-15-927-2021, https://doi.org/10.5194/tc-15-927-2021, 2021
Short summary
Short summary
We present a map of rock glacier motion over parts of the northern Tien Shan and time series of surface speed for six of them over almost 70 years.
This is by far the most detailed investigation of this kind available for central Asia.
We detect a 2- to 4-fold increase in rock glacier motion between the 1950s and present, which we attribute to atmospheric warming.
Relative to the shrinking glaciers in the region, this implies increased importance of periglacial sediment transport.
Alia L. Khan, Heidi M. Dierssen, Ted A. Scambos, Juan Höfer, and Raul R. Cordero
The Cryosphere, 15, 133–148, https://doi.org/10.5194/tc-15-133-2021, https://doi.org/10.5194/tc-15-133-2021, 2021
Short summary
Short summary
We present radiative forcing (RF) estimates by snow algae in the Antarctic Peninsula (AP) region from multi-year measurements of solar radiation and ground-based hyperspectral characterization of red and green snow algae collected during a brief field expedition in austral summer 2018. Mean daily RF was double for green (~26 W m−2) vs. red (~13 W m−2) snow algae during the peak growing season, which is on par with midlatitude dust attributions capable of advancing snowmelt.
Andreas Alexander, Jaroslav Obu, Thomas V. Schuler, Andreas Kääb, and Hanne H. Christiansen
The Cryosphere, 14, 4217–4231, https://doi.org/10.5194/tc-14-4217-2020, https://doi.org/10.5194/tc-14-4217-2020, 2020
Short summary
Short summary
In this study we present subglacial air, ice and sediment temperatures from within the basal drainage systems of two cold-based glaciers on Svalbard during late spring and the summer melt season. We put the data into the context of air temperature and rainfall at the glacier surface and show the importance of surface events on the subglacial thermal regime and erosion around basal drainage channels. Observed vertical erosion rates thereby reachup to 0.9 m d−1.
Christopher Chambers, Ralf Greve, Bas Altena, and Pierre-Marie Lefeuvre
The Cryosphere, 14, 3747–3759, https://doi.org/10.5194/tc-14-3747-2020, https://doi.org/10.5194/tc-14-3747-2020, 2020
Short summary
Short summary
The topography of the rock below the Greenland ice sheet is not well known. One long valley appears as a line of dips because of incomplete data. So we use ice model simulations that unblock this valley, and these create a watercourse that may represent a form of river over 1000 km long under the ice. When we melt ice at the bottom of the ice sheet only in the deep interior, water can flow down the valley only when the valley is unblocked. It may have developed while an ice sheet was present.
Julie Z. Miller, David G. Long, Kenneth C. Jezek, Joel T. Johnson, Mary J. Brodzik, Christopher A. Shuman, Lora S. Koenig, and Ted A. Scambos
The Cryosphere, 14, 2809–2817, https://doi.org/10.5194/tc-14-2809-2020, https://doi.org/10.5194/tc-14-2809-2020, 2020
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
Short summary
Short summary
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.
Jaroslav Obu, Sebastian Westermann, Gonçalo Vieira, Andrey Abramov, Megan Ruby Balks, Annett Bartsch, Filip Hrbáček, Andreas Kääb, and Miguel Ramos
The Cryosphere, 14, 497–519, https://doi.org/10.5194/tc-14-497-2020, https://doi.org/10.5194/tc-14-497-2020, 2020
Short summary
Short summary
Little is known about permafrost in the Antarctic outside of the few research stations. We used a simple equilibrium permafrost model to estimate permafrost temperatures in the whole Antarctic. The lowest permafrost temperature on Earth is −36 °C in the Queen Elizabeth Range in the Transantarctic Mountains. Temperatures are commonly between −23 and −18 °C in mountainous areas rising above the Antarctic Ice Sheet, between −14 and −8 °C in coastal areas, and up to 0 °C on the Antarctic Peninsula.
Désirée Treichler, Andreas Kääb, Nadine Salzmann, and Chong-Yu Xu
The Cryosphere, 13, 2977–3005, https://doi.org/10.5194/tc-13-2977-2019, https://doi.org/10.5194/tc-13-2977-2019, 2019
Short summary
Short summary
Glacier growth such as that found on the Tibetan Plateau (TP) is counterintuitive in a warming world. Climate models and meteorological data are conflicting about the reasons for this glacier anomaly. We quantify the glacier changes in High Mountain Asia using satellite laser altimetry as well as the growth of over 1300 inland lakes on the TP. Our study suggests that increased summer precipitation is likely the largest contributor to the recently observed increases in glacier and lake masses.
Andreas Kääb, Bas Altena, and Joseph Mascaro
Hydrol. Earth Syst. Sci., 23, 4233–4247, https://doi.org/10.5194/hess-23-4233-2019, https://doi.org/10.5194/hess-23-4233-2019, 2019
Short summary
Short summary
Knowledge of water surface velocities in rivers is useful for understanding a wide range of processes and systems, but is difficult to measure over large reaches. Here, we present a novel method to exploit near-simultaneous imagery produced by the Planet cubesat constellation to track river ice floes and estimate water surface velocities. We demonstrate the method for a 60 km long reach of the Amur River and a 200 km long reach of the Yukon River.
B. Altena, O. N. Haga, C. Nuth, and A. Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-2-W13, 1723–1727, https://doi.org/10.5194/isprs-archives-XLII-2-W13-1723-2019, https://doi.org/10.5194/isprs-archives-XLII-2-W13-1723-2019, 2019
Daniel Falaschi, Andreas Kääb, Frank Paul, Takeo Tadono, Juan Antonio Rivera, and Luis Eduardo Lenzano
The Cryosphere, 13, 997–1004, https://doi.org/10.5194/tc-13-997-2019, https://doi.org/10.5194/tc-13-997-2019, 2019
Short summary
Short summary
In March 2007, the Leñas Glacier in the Central Andes of Argentina collapsed and released an ice avalanche that travelled a distance of 2 km. We analysed aerial photos, satellite images and field evidence to investigate the evolution of the glacier from the 1950s through the present day. A clear potential trigger of the collapse could not be identified from available meteorological and seismic data, nor could a significant change in glacier geometry leading to glacier instability be detected.
Robert McNabb, Christopher Nuth, Andreas Kääb, and Luc Girod
The Cryosphere, 13, 895–910, https://doi.org/10.5194/tc-13-895-2019, https://doi.org/10.5194/tc-13-895-2019, 2019
Short summary
Short summary
Estimating glacier changes involves measuring elevation changes, often using elevation models derived from satellites. Many elevation models have data gaps (voids), which affect estimates of glacier change. We compare 11 methods for interpolating voids, finding that some methods bias estimates of glacier change by up to 20 %, though most methods have a smaller effect. Some methods produce reliable results even with large void areas, suggesting that noisy elevation data are still useful.
Luc Girod, Niels Ivar Nielsen, Frédérique Couderette, Christopher Nuth, and Andreas Kääb
Geosci. Instrum. Method. Data Syst., 7, 277–288, https://doi.org/10.5194/gi-7-277-2018, https://doi.org/10.5194/gi-7-277-2018, 2018
Short summary
Short summary
Historical surveys performed through the use of aerial photography gave us the first maps of the Arctic. Nearly a century later, a renewed interest in studying the Arctic is rising from the need to understand and quantify climate change. It is therefore time to dig up the archives and extract the maximum of information from the images using the most modern methods. In this study, we show that the aerial survey of Svalbard in 1936–38 provides us with valuable data on the archipelago's glaciers.
Adrien Gilbert, Silvan Leinss, Jeffrey Kargel, Andreas Kääb, Simon Gascoin, Gregory Leonard, Etienne Berthier, Alina Karki, and Tandong Yao
The Cryosphere, 12, 2883–2900, https://doi.org/10.5194/tc-12-2883-2018, https://doi.org/10.5194/tc-12-2883-2018, 2018
Short summary
Short summary
In Tibet, two glaciers suddenly collapsed in summer 2016 and produced two gigantic ice avalanches, killing nine people. This kind of phenomenon is extremely rare. By combining a detailed modelling study and high-resolution satellite observations, we show that the event was triggered by an increasing meltwater supply in the fine-grained material underneath the two glaciers. Contrary to what is often thought, this event is not linked to a change in the thermal condition at the glacier base.
Martina Barandun, Matthias Huss, Ryskul Usubaliev, Erlan Azisov, Etienne Berthier, Andreas Kääb, Tobias Bolch, and Martin Hoelzle
The Cryosphere, 12, 1899–1919, https://doi.org/10.5194/tc-12-1899-2018, https://doi.org/10.5194/tc-12-1899-2018, 2018
Short summary
Short summary
In this study, we used three independent methods (in situ measurements, comparison of digital elevation models and modelling) to reconstruct the mass change from 2000 to 2016 for three glaciers in the Tien Shan and Pamir. Snow lines observed on remote sensing images were used to improve conventional modelling by constraining a mass balance model. As a result, glacier mass changes for unmeasured years and glaciers can be better assessed. Substantial mass loss was confirmed for the three glaciers.
Yongmei Gong, Thomas Zwinger, Jan Åström, Bas Altena, Thomas Schellenberger, Rupert Gladstone, and John C. Moore
The Cryosphere, 12, 1563–1577, https://doi.org/10.5194/tc-12-1563-2018, https://doi.org/10.5194/tc-12-1563-2018, 2018
Short summary
Short summary
In this study we apply a discrete element model capable of simulating ice fracturing. A microscopic-scale discrete process is applied in addition to a continuum ice dynamics model to investigate the mechanisms facilitated by basal meltwater production, surface meltwater and ice crack opening, for the surge in Basin 3, Austfonna ice cap. The discrete element model is used to locate the ice cracks that can penetrate though the full thickness of the glacier and deliver surface water to the bed.
Chiyuki Narama, Mirlan Daiyrov, Murataly Duishonakunov, Takeo Tadono, Hayato Sato, Andreas Kääb, Jinro Ukita, and Kanatbek Abdrakhmatov
Nat. Hazards Earth Syst. Sci., 18, 983–995, https://doi.org/10.5194/nhess-18-983-2018, https://doi.org/10.5194/nhess-18-983-2018, 2018
Short summary
Short summary
Four large drainages from glacial lakes occurred during 2006–2014 in the western Teskey Range, Kyrgyzstan. These floods caused extensive damage, killing people and livestock, as well as destroying property and crops. Due to their subsurface outlet, we refer to these short-lived glacial lakes as being of the
tunnel-type, a type that drastically grows and drains over a few months.
Solveig H. Winsvold, Andreas Kääb, Christopher Nuth, Liss M. Andreassen, Ward J. J. van Pelt, and Thomas Schellenberger
The Cryosphere, 12, 867–890, https://doi.org/10.5194/tc-12-867-2018, https://doi.org/10.5194/tc-12-867-2018, 2018
Alex S. Gardner, Geir Moholdt, Ted Scambos, Mark Fahnstock, Stefan Ligtenberg, Michiel van den Broeke, and Johan Nilsson
The Cryosphere, 12, 521–547, https://doi.org/10.5194/tc-12-521-2018, https://doi.org/10.5194/tc-12-521-2018, 2018
Short summary
Short summary
We map present-day Antarctic surface velocities from Landsat imagery and compare to earlier estimates from radar. Flow accelerations across the grounding lines of West Antarctica's Amundsen Sea Embayment, Getz Ice Shelf and the western Antarctic Peninsula, account for 89 % of the observed increase in ice discharge. In contrast, glaciers draining the East Antarctic have been remarkably stable. Our work suggests that patterns of mass loss are part of a longer-term phase of enhanced flow.
B. Altena, A. Mousivand, J. Mascaro, and A. Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-3-W3, 7–11, https://doi.org/10.5194/isprs-archives-XLII-3-W3-7-2017, https://doi.org/10.5194/isprs-archives-XLII-3-W3-7-2017, 2017
Andreas Kääb, Bas Altena, and Joseph Mascaro
Nat. Hazards Earth Syst. Sci., 17, 627–639, https://doi.org/10.5194/nhess-17-627-2017, https://doi.org/10.5194/nhess-17-627-2017, 2017
Short summary
Short summary
We evaluate for the first time a new class of optical satellite images for measuring Earth surface displacements due to earthquakes – images from cubesats. The PlanetScope cubesats used in this study are 10 cm × 10 cm × 30 cm small and standardized satellites. Around 120 of these cubesats orbit around Earth and are about to provide daily 2–4 m resolution images of the entire land surface of the Earth.
Luc Girod, Christopher Nuth, Andreas Kääb, Bernd Etzelmüller, and Jack Kohler
The Cryosphere, 11, 827–840, https://doi.org/10.5194/tc-11-827-2017, https://doi.org/10.5194/tc-11-827-2017, 2017
Short summary
Short summary
While gathering data on a changing environment is often a costly and complicated endeavour, it is also the backbone of all research. What if one could measure elevation change by just strapping a camera and a hiking GPS under an helicopter or a small airplane used for transportation and gather data on the ground bellow the flight path? In this article, we present a way to do exactly that and show an example survey where it helped compute the volume of ice lost by a glacier in Svalbard.
Tazio Strozzi, Andreas Kääb, and Thomas Schellenberger
The Cryosphere, 11, 553–566, https://doi.org/10.5194/tc-11-553-2017, https://doi.org/10.5194/tc-11-553-2017, 2017
Short summary
Short summary
The strong atmospheric warming observed since the 1990s in polar regions requires quantifying the contribution to sea level rise of glaciers and ice caps, but for large areas we do not have much information on ice dynamic fluctuations. The recent increase in satellite data opens up new possibilities to monitor ice flow. We observed over Stonebreen on Edgeøya (Svalbard) a strong increase since 2012 in ice surface velocity along with a decrease in volume and an advance in frontal extension.
Thomas Schellenberger, Thorben Dunse, Andreas Kääb, Thomas Vikhamar Schuler, Jon Ove Hagen, and Carleen H. Reijmer
The Cryosphere Discuss., https://doi.org/10.5194/tc-2017-5, https://doi.org/10.5194/tc-2017-5, 2017
Preprint withdrawn
Short summary
Short summary
Basin-3, NE-Svalbard, was still surging with 10 m d-1 in July 2016. After a speed peak of 18.8 m d-1 in Dec 2012/Jan 2013, speed-ups are overlying the fast flow every summer. The glacier is massively calving icebergs (5.2 Gt yr-1 ~ 2 L drinking water for every human being daily!) which in the same order of magnitude as all other Svalbard glaciers together.
Since autumn 2015 also Basin-2 is surging with maximum velocities of 8.7 m d-1, an advance of more than 2 km and a mass loss of 0.7 Gt yr-1.
Byeong-Hoon Kim, Choon-Ki Lee, Ki-Weon Seo, Won Sang Lee, and Ted Scambos
The Cryosphere, 10, 2971–2980, https://doi.org/10.5194/tc-10-2971-2016, https://doi.org/10.5194/tc-10-2971-2016, 2016
Short summary
Short summary
Kamb Ice Stream (KIS) in Antarctica ceased rapid ice flow approximately 160 years ago, still influencing on the current mass balance of the West Antarctic Ice Sheet. We identify two previously unknown subglacial lakes beneath the stagnated trunk of the KIS. Rapid fill-drain hydrologic events over several months indicate that the lakes are probably connected by a subglacial drainage network. Our findings support previously published conceptual models of the KIS shutdown.
Désirée Treichler and Andreas Kääb
The Cryosphere, 10, 2129–2146, https://doi.org/10.5194/tc-10-2129-2016, https://doi.org/10.5194/tc-10-2129-2016, 2016
Short summary
Short summary
Satellite data are often the only source of information on mountain glaciers. We show that data from ICESat laser satellite can accurately reflect glacier volume development in 2003–2008, also for individual years. We detect a spatially varying elevation bias in commonly used data sets, and provide a correction that strongly increases the significance of the glacier change estimates – a crucial driver of climate-induced meltwater changes that directly affect the life of lowland populations.
J. M. van Wessem, S. R. M. Ligtenberg, C. H. Reijmer, W. J. van de Berg, M. R. van den Broeke, N. E. Barrand, E. R. Thomas, J. Turner, J. Wuite, T. A. Scambos, and E. van Meijgaard
The Cryosphere, 10, 271–285, https://doi.org/10.5194/tc-10-271-2016, https://doi.org/10.5194/tc-10-271-2016, 2016
Short summary
Short summary
This study presents the first high-resolution (5.5 km) modelled estimate of surface mass balance (SMB) over the period 1979–2014 for the Antarctic Peninsula (AP). Precipitation (snowfall and rain) largely determines the SMB, and is exceptionally high over the western mountain slopes, with annual values > 4 m water equivalent. Snowmelt is widespread over the AP, but only runs off into the ocean at some locations: the Larsen B,C, and Wilkins ice shelves, and along the north-western mountains.
A. Pope, T. A. Scambos, M. Moussavi, M. Tedesco, M. Willis, D. Shean, and S. Grigsby
The Cryosphere, 10, 15–27, https://doi.org/10.5194/tc-10-15-2016, https://doi.org/10.5194/tc-10-15-2016, 2016
Short summary
Short summary
Liquid water stored on the surface of ice sheets and glaciers, such as that in surface (supraglacial) lakes, plays a key role in the glacial hydrological system. Multispectral remote sensing can be used to detect lakes and estimate their depth. Here, we use in situ data to assess lake depth retrieval using the recently launched Landsat 8. We validate Landsat 8-derived depths and provide suggestions for future applications. We apply our method to a case study are in Greenland for summer 2014.
T. Schellenberger, T. Dunse, A. Kääb, J. Kohler, and C. H. Reijmer
The Cryosphere, 9, 2339–2355, https://doi.org/10.5194/tc-9-2339-2015, https://doi.org/10.5194/tc-9-2339-2015, 2015
Short summary
Short summary
Kronebreen and Kongsbreen are among the fastest flowing glaciers on Svalbard, and surface speeds reached up to 3.2m d-1 at Kronebreen in summer 2013 and 2.7m d-1 at Kongsbreen in late autumn 2012 as retrieved from SAR satellite data. Both glaciers retreated significantly during the observation period, Kongsbreen up to 1800m or 2.5km2 and Kronebreen up to 850m or 2.8km2. Both glaciers are important contributors to the total dynamic mass loss from the Svalbard archipelago.
C. Lavoie, E. W. Domack, E. C. Pettit, T. A. Scambos, R. D. Larter, H.-W. Schenke, K. C. Yoo, J. Gutt, J. Wellner, M. Canals, J. B. Anderson, and D. Amblas
The Cryosphere, 9, 613–629, https://doi.org/10.5194/tc-9-613-2015, https://doi.org/10.5194/tc-9-613-2015, 2015
A. Kääb, D. Treichler, C. Nuth, and E. Berthier
The Cryosphere, 9, 557–564, https://doi.org/10.5194/tc-9-557-2015, https://doi.org/10.5194/tc-9-557-2015, 2015
Short summary
Short summary
Based on satellite laser altimetry over the Pamir--Karakoram Himalaya we detect strongest elevation losses over east Nyainqentanglha Shan and Spiti--Lahaul but slight elevation gains over west Kunlun Shan rather than over Karakoram. The current sea-level contribution of Pamir--Karakoram Himalaya glaciers is about 10% of the total global contribution of glaciers outside the ice sheets. We also improve estimates of glacier imbalance contribution to river discharge in the Himalayas.
T. Dunse, T. Schellenberger, J. O. Hagen, A. Kääb, T. V. Schuler, and C. H. Reijmer
The Cryosphere, 9, 197–215, https://doi.org/10.5194/tc-9-197-2015, https://doi.org/10.5194/tc-9-197-2015, 2015
T. A. Scambos, E. Berthier, T. Haran, C. A. Shuman, A. J. Cook, S. R. M. Ligtenberg, and J. Bohlander
The Cryosphere, 8, 2135–2145, https://doi.org/10.5194/tc-8-2135-2014, https://doi.org/10.5194/tc-8-2135-2014, 2014
Short summary
Short summary
This study of one of the most rapidly changing glacier regions on earth -- the Antarctic Peninsula -- uses two types of satellite data to measure the rates of ice loss in detail for the individual glaciers. The satellite data is laser altimetry from ICESat and stereo image DEM differences. The results show that 24..9 ± 7.8 billion tons of ice are lost from the region north of 66°S on the peninsula each year. The majority of the data cover 2003-2008.
A. Kääb, L. Girod, and I. Berthling
The Cryosphere, 8, 1041–1056, https://doi.org/10.5194/tc-8-1041-2014, https://doi.org/10.5194/tc-8-1041-2014, 2014
A. Kääb, M. Lamare, and M. Abrams
Hydrol. Earth Syst. Sci., 17, 4671–4683, https://doi.org/10.5194/hess-17-4671-2013, https://doi.org/10.5194/hess-17-4671-2013, 2013
K. Kawamura, J. P. Severinghaus, M. R. Albert, Z. R. Courville, M. A. Fahnestock, T. Scambos, E. Shields, and C. A. Shuman
Atmos. Chem. Phys., 13, 11141–11155, https://doi.org/10.5194/acp-13-11141-2013, https://doi.org/10.5194/acp-13-11141-2013, 2013
C. Nuth, J. Kohler, M. König, A. von Deschwanden, J. O. Hagen, A. Kääb, G. Moholdt, and R. Pettersson
The Cryosphere, 7, 1603–1621, https://doi.org/10.5194/tc-7-1603-2013, https://doi.org/10.5194/tc-7-1603-2013, 2013
J. Gardelle, E. Berthier, Y. Arnaud, and A. Kääb
The Cryosphere, 7, 1263–1286, https://doi.org/10.5194/tc-7-1263-2013, https://doi.org/10.5194/tc-7-1263-2013, 2013
Related subject area
Discipline: Glaciers | Subject: Remote Sensing
GLAcier Feature Tracking testkit (GLAFT): a statistically and physically based framework for evaluating glacier velocity products derived from optical satellite image feature tracking
Cast shadows reveal changes in glacier surface elevation
Characterizing the surge behaviour and associated ice-dammed lake evolution of the Kyagar Glacier in the Karakoram
Constraining regional glacier reconstructions using past ice thickness of deglaciating areas – a case study in the European Alps
Climatic control on seasonal variations in mountain glacier surface velocity
High-resolution debris-cover mapping using UAV-derived thermal imagery: limits and opportunities
Out-of-the-box calving front detection method using deep-learning
Automated ArcticDEM iceberg detection tool: insights into area and volume distributions, and their potential application to satellite imagery and modelling of glacier–iceberg–ocean systems
Glacier extraction based on high-spatial-resolution remote-sensing images using a deep-learning approach with attention mechanism
TermPicks: a century of Greenland glacier terminus data for use in scientific and machine learning applications
Surge dynamics of Shisper Glacier revealed by time-series correlation of optical satellite images and their utility to substantiate a generalized sliding law
Offset of MODIS land surface temperatures from in situ air temperatures in the upper Kaskawulsh Glacier region (St. Elias Mountains) indicates near-surface temperature inversions
Three different glacier surges at a spot: what satellites observe and what not
Correlation dispersion as a measure to better estimate uncertainty in remotely sensed glacier displacements
Glacier and rock glacier changes since the 1950s in the La Laguna catchment, Chile
Brief communication: Increased glacier mass loss in the Russian High Arctic (2010–2017)
Contrasting surface velocities between lake- and land-terminating glaciers in the Himalayan region
Aerodynamic roughness length of crevassed tidewater glaciers from UAV mapping
Image classification of marine-terminating outlet glaciers in Greenland using deep learning methods
Brief communication: Detection of glacier surge activity using cloud computing of Sentinel-1 radar data
InSAR-based characterization of rock glacier movement in the Uinta Mountains, Utah, USA
Surface composition of debris-covered glaciers across the Himalaya using linear spectral unmixing of Landsat 8 OLI imagery
Mapping seasonal glacier melt across the Hindu Kush Himalaya with time series synthetic aperture radar (SAR)
Estimating surface mass balance patterns from unoccupied aerial vehicle measurements in the ablation area of the Morteratsch–Pers glacier complex (Switzerland)
High-resolution topography of the Antarctic Peninsula combining the TanDEM-X DEM and Reference Elevation Model of Antarctica (REMA) mosaic
Measuring the state and temporal evolution of glaciers in Alaska and Yukon using synthetic-aperture-radar-derived (SAR-derived) 3D time series of glacier surface flow
Tracking changes in the area, thickness, and volume of the Thwaites tabular iceberg “B30” using satellite altimetry and imagery
Analyzing glacier retreat and mass balances using aerial and UAV photogrammetry in the Ötztal Alps, Austria
Surges of Harald Moltke Bræ, north-western Greenland: seasonal modulation and initiation at the terminus
Brief communication: An empirical relation between center frequency and measured thickness for radar sounding of temperate glaciers
Glacier Image Velocimetry: an open-source toolbox for easy and rapid calculation of high-resolution glacier velocity fields
Calving Front Machine (CALFIN): glacial termini dataset and automated deep learning extraction method for Greenland, 1972–2019
Annual and inter-annual variability and trends of albedo of Icelandic glaciers
Observing traveling waves in glaciers with remote sensing: new flexible time series methods and application to Sermeq Kujalleq (Jakobshavn Isbræ), Greenland
Detecting seasonal ice dynamics in satellite images
Sharp contrasts in observed and modeled crevasse patterns at Greenland's marine terminating glaciers
Variability in glacier albedo and links to annual mass balance for the gardens of Eden and Allah, Southern Alps, New Zealand
The seasonal evolution of albedo across glaciers and the surrounding landscape of Taylor Valley, Antarctica
Recent glacier and lake changes in High Mountain Asia and their relation to precipitation changes
Multisensor validation of tidewater glacier flow fields derived from synthetic aperture radar (SAR) intensity tracking
Detecting dynamics of cave floor ice with selective cloud-to-cloud approach
Changes of the tropical glaciers throughout Peru between 2000 and 2016 – mass balance and area fluctuations
Iceberg topography and volume classification using TanDEM-X interferometry
Automatically delineating the calving front of Jakobshavn Isbræ from multitemporal TerraSAR-X images: a deep learning approach
Sensitivity of glacier volume change estimation to DEM void interpolation
Change detection of bare-ice albedo in the Swiss Alps
Characterizing the behaviour of surge- and non-surge-type glaciers in the Kingata Mountains, eastern Pamir, from 1999 to 2016
Automated detection of ice cliffs within supraglacial debris cover
Brief communication: Unabated wastage of the Juneau and Stikine icefields (southeast Alaska) in the early 21st century
Whyjay Zheng, Shashank Bhushan, Maximillian Van Wyk De Vries, William Kochtitzky, David Shean, Luke Copland, Christine Dow, Renette Jones-Ivey, and Fernando Pérez
The Cryosphere, 17, 4063–4078, https://doi.org/10.5194/tc-17-4063-2023, https://doi.org/10.5194/tc-17-4063-2023, 2023
Short summary
Short summary
We design and propose a method that can evaluate the quality of glacier velocity maps. The method includes two numbers that we can calculate for each velocity map. Based on statistics and ice flow physics, velocity maps with numbers close to the recommended values are considered to have good quality. We test the method using the data from Kaskawulsh Glacier, Canada, and release an open-sourced software tool called GLAcier Feature Tracking testkit (GLAFT) to help users assess their velocity maps.
Monika Pfau, Georg Veh, and Wolfgang Schwanghart
The Cryosphere, 17, 3535–3551, https://doi.org/10.5194/tc-17-3535-2023, https://doi.org/10.5194/tc-17-3535-2023, 2023
Short summary
Short summary
Cast shadows have been a recurring problem in remote sensing of glaciers. We show that the length of shadows from surrounding mountains can be used to detect gains or losses in glacier elevation.
Guanyu Li, Mingyang Lv, Duncan J. Quincey, Liam S. Taylor, Xinwu Li, Shiyong Yan, Yidan Sun, and Huadong Guo
The Cryosphere, 17, 2891–2907, https://doi.org/10.5194/tc-17-2891-2023, https://doi.org/10.5194/tc-17-2891-2023, 2023
Short summary
Short summary
Kyagar Glacier in the Karakoram is well known for its surge history and its frequent blocking of the downstream valley, leading to a series of high-magnitude glacial lake outburst floods. Using it as a test bed, we develop a new approach for quantifying surge behaviour using successive digital elevation models. This method could be applied to other surge studies. Combined with the results from optical satellite images, we also reconstruct the surge process in unprecedented detail.
Christian Sommer, Johannes J. Fürst, Matthias Huss, and Matthias H. Braun
The Cryosphere, 17, 2285–2303, https://doi.org/10.5194/tc-17-2285-2023, https://doi.org/10.5194/tc-17-2285-2023, 2023
Short summary
Short summary
Knowledge on the volume of glaciers is important to project future runoff. Here, we present a novel approach to reconstruct the regional ice thickness distribution from easily available remote-sensing data. We show that past ice thickness, derived from spaceborne glacier area and elevation datasets, can constrain the estimated ice thickness. Based on the unique glaciological database of the European Alps, the approach will be most beneficial in regions without direct thickness measurements.
Ugo Nanni, Dirk Scherler, Francois Ayoub, Romain Millan, Frederic Herman, and Jean-Philippe Avouac
The Cryosphere, 17, 1567–1583, https://doi.org/10.5194/tc-17-1567-2023, https://doi.org/10.5194/tc-17-1567-2023, 2023
Short summary
Short summary
Surface melt is a major factor driving glacier movement. Using satellite images, we have tracked the movements of 38 glaciers in the Pamirs over 7 years, capturing their responses to rapid meteorological changes with unprecedented resolution. We show that in spring, glacier accelerations propagate upglacier, while in autumn, they propagate downglacier – all resulting from changes in meltwater input. This provides critical insights into the interplay between surface melt and glacier movement.
Deniz Tobias Gök, Dirk Scherler, and Leif Stefan Anderson
The Cryosphere, 17, 1165–1184, https://doi.org/10.5194/tc-17-1165-2023, https://doi.org/10.5194/tc-17-1165-2023, 2023
Short summary
Short summary
We performed high-resolution debris-thickness mapping using land surface temperature (LST) measured from an unpiloted aerial vehicle (UAV) at various times of the day. LSTs from UAVs require calibration that varies in time. We test two approaches to quantify supraglacial debris cover, and we find that the non-linearity of the relationship between LST and debris thickness increases with LST. Choosing the best model to predict debris thickness depends on the time of the day and the terrain aspect.
Oskar Herrmann, Nora Gourmelon, Thorsten Seehaus, Andreas Maier, Johannes Fürst, Matthias Holger Braun, and Vincent Christlein
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-34, https://doi.org/10.5194/tc-2023-34, 2023
Revised manuscript accepted for TC
Short summary
Short summary
Delineating calving fronts of marine-terminating glaciers in satellite images is a labour-intensive task. We propose a method based on deep learning that automates this task. We choose a deep learning framework that adapts to any given dataset without needing deep learning expertise. The method is evaluated on a benchmark dataset for calving front detection and glacier zone segmentation. The framework can beat the benchmark baseline without major modifications.
Connor J. Shiggins, James M. Lea, and Stephen Brough
The Cryosphere, 17, 15–32, https://doi.org/10.5194/tc-17-15-2023, https://doi.org/10.5194/tc-17-15-2023, 2023
Short summary
Short summary
Iceberg detection is spatially and temporally limited around the Greenland Ice Sheet. This study presents a new, accessible workflow to automatically detect icebergs from timestamped ArcticDEM strip data. The workflow successfully produces comparable output to manual digitisation, with results revealing new iceberg area-to-volume conversion equations that can be widely applied to datasets where only iceberg outlines can be extracted (e.g. optical and SAR imagery).
Xinde Chu, Xiaojun Yao, Hongyu Duan, Cong Chen, Jing Li, and Wenlong Pang
The Cryosphere, 16, 4273–4289, https://doi.org/10.5194/tc-16-4273-2022, https://doi.org/10.5194/tc-16-4273-2022, 2022
Short summary
Short summary
The available remote-sensing data are increasingly abundant, and the efficient and rapid acquisition of glacier boundaries based on these data is currently a frontier issue in glacier research. In this study, we designed a complete solution to automatically extract glacier outlines from the high-resolution images. Compared with other methods, our method achieves the best performance for glacier boundary extraction in parts of the Tanggula Mountains, Kunlun Mountains and Qilian Mountains.
Sophie Goliber, Taryn Black, Ginny Catania, James M. Lea, Helene Olsen, Daniel Cheng, Suzanne Bevan, Anders Bjørk, Charlie Bunce, Stephen Brough, J. Rachel Carr, Tom Cowton, Alex Gardner, Dominik Fahrner, Emily Hill, Ian Joughin, Niels J. Korsgaard, Adrian Luckman, Twila Moon, Tavi Murray, Andrew Sole, Michael Wood, and Enze Zhang
The Cryosphere, 16, 3215–3233, https://doi.org/10.5194/tc-16-3215-2022, https://doi.org/10.5194/tc-16-3215-2022, 2022
Short summary
Short summary
Terminus traces have been used to understand how Greenland's glaciers have changed over time; however, manual digitization is time-intensive, and a lack of coordination leads to duplication of efforts. We have compiled a dataset of over 39 000 terminus traces for 278 glaciers for scientific and machine learning applications. We also provide an overview of an updated version of the Google Earth Engine Digitization Tool (GEEDiT), which has been developed specifically for the Greenland Ice Sheet.
Flavien Beaud, Saif Aati, Ian Delaney, Surendra Adhikari, and Jean-Philippe Avouac
The Cryosphere, 16, 3123–3148, https://doi.org/10.5194/tc-16-3123-2022, https://doi.org/10.5194/tc-16-3123-2022, 2022
Short summary
Short summary
Understanding sliding at the bed of glaciers is essential to understand the future of sea-level rise and glacier-related hazards. Yet there is currently no universal law to describe this mechanism. We propose a universal glacier sliding law and a method to qualitatively constrain it. We use satellite remote sensing to create velocity maps over 6 years at Shisper Glacier, Pakistan, including its recent surge, and show that the observations corroborate the generalized theory.
Ingalise Kindstedt, Kristin M. Schild, Dominic Winski, Karl Kreutz, Luke Copland, Seth Campbell, and Erin McConnell
The Cryosphere, 16, 3051–3070, https://doi.org/10.5194/tc-16-3051-2022, https://doi.org/10.5194/tc-16-3051-2022, 2022
Short summary
Short summary
We show that neither the large spatial footprint of the MODIS sensor nor poorly constrained snow emissivity values explain the observed cold offset in MODIS land surface temperatures (LSTs) in the St. Elias. Instead, the offset is most prominent under conditions associated with near-surface temperature inversions. This work represents an advance in the application of MODIS LSTs to glaciated alpine regions, where we often depend solely on remote sensing products for temperature information.
Frank Paul, Livia Piermattei, Désirée Treichler, Lin Gilbert, Luc Girod, Andreas Kääb, Ludivine Libert, Thomas Nagler, Tazio Strozzi, and Jan Wuite
The Cryosphere, 16, 2505–2526, https://doi.org/10.5194/tc-16-2505-2022, https://doi.org/10.5194/tc-16-2505-2022, 2022
Short summary
Short summary
Glacier surges are widespread in the Karakoram and have been intensely studied using satellite data and DEMs. We use time series of such datasets to study three glacier surges in the same region of the Karakoram. We found strongly contrasting advance rates and flow velocities, maximum velocities of 30 m d−1, and a change in the surge mechanism during a surge. A sensor comparison revealed good agreement, but steep terrain and the two smaller glaciers caused limitations for some of them.
Bas Altena, Andreas Kääb, and Bert Wouters
The Cryosphere, 16, 2285–2300, https://doi.org/10.5194/tc-16-2285-2022, https://doi.org/10.5194/tc-16-2285-2022, 2022
Short summary
Short summary
Repeat overflights of satellites are used to estimate surface displacements. However, such products lack a simple error description for individual measurements, but variation in precision occurs, since the calculation is based on the similarity of texture. Fortunately, variation in precision manifests itself in the correlation peak, which is used for the displacement calculation. This spread is used to make a connection to measurement precision, which can be of great use for model inversion.
Benjamin Aubrey Robson, Shelley MacDonell, Álvaro Ayala, Tobias Bolch, Pål Ringkjøb Nielsen, and Sebastián Vivero
The Cryosphere, 16, 647–665, https://doi.org/10.5194/tc-16-647-2022, https://doi.org/10.5194/tc-16-647-2022, 2022
Short summary
Short summary
This work uses satellite and aerial data to study glaciers and rock glacier changes in La Laguna catchment within the semi-arid Andes of Chile, where ice melt is an important factor in river flow. The results show the rate of ice loss of Tapado Glacier has been increasing since the 1950s, which possibly relates to a dryer, warmer climate over the previous decades. Several rock glaciers show high surface velocities and elevation changes between 2012 and 2020, indicating they may be ice-rich.
Christian Sommer, Thorsten Seehaus, Andrey Glazovsky, and Matthias H. Braun
The Cryosphere, 16, 35–42, https://doi.org/10.5194/tc-16-35-2022, https://doi.org/10.5194/tc-16-35-2022, 2022
Short summary
Short summary
Arctic glaciers have been subject to extensive warming due to global climate change, yet their contribution to sea level rise has been relatively small in the past. In this study we provide mass changes of most glaciers of the Russian High Arctic (Franz Josef Land, Severnaya Zemlya, Novaya Zemlya). We use TanDEM-X satellite measurements to derive glacier surface elevation changes. Our results show an increase in glacier mass loss and a sea level rise contribution of 0.06 mm/a (2010–2017).
Jan Bouke Pronk, Tobias Bolch, Owen King, Bert Wouters, and Douglas I. Benn
The Cryosphere, 15, 5577–5599, https://doi.org/10.5194/tc-15-5577-2021, https://doi.org/10.5194/tc-15-5577-2021, 2021
Short summary
Short summary
About 10 % of Himalayan glaciers flow directly into lakes. This study finds, using satellite imagery, that such glaciers show higher flow velocities than glaciers without ice–lake contact. In particular near the glacier tongue the impact of a lake on the glacier flow can be dramatic. The development of current and new meltwater bodies will influence the flow of an increasing number of Himalayan glaciers in the future, a scenario not currently considered in regional ice loss projections.
Armin Dachauer, Richard Hann, and Andrew J. Hodson
The Cryosphere, 15, 5513–5528, https://doi.org/10.5194/tc-15-5513-2021, https://doi.org/10.5194/tc-15-5513-2021, 2021
Short summary
Short summary
This study investigated the aerodynamic roughness length (z0) – an important parameter to determine the surface roughness – of crevassed tidewater glaciers on Svalbard using drone data. The results point out that the range of z0 values across a crevassed glacier is large but in general significantly higher compared to non-crevassed glacier surfaces. The UAV approach proved to be an ideal tool to provide distributed z0 estimates of crevassed glaciers which can be used to model turbulent fluxes.
Melanie Marochov, Chris R. Stokes, and Patrice E. Carbonneau
The Cryosphere, 15, 5041–5059, https://doi.org/10.5194/tc-15-5041-2021, https://doi.org/10.5194/tc-15-5041-2021, 2021
Short summary
Short summary
Research into the use of deep learning for pixel-level classification of landscapes containing marine-terminating glaciers is lacking. We adapt a novel and transferable deep learning workflow to classify satellite imagery containing marine-terminating outlet glaciers in Greenland. Our workflow achieves high accuracy and mimics human visual performance, potentially providing a useful tool to monitor glacier change and further understand the impacts of climate change in complex glacial settings.
Paul Willem Leclercq, Andreas Kääb, and Bas Altena
The Cryosphere, 15, 4901–4907, https://doi.org/10.5194/tc-15-4901-2021, https://doi.org/10.5194/tc-15-4901-2021, 2021
Short summary
Short summary
In this study we present a novel method to detect glacier surge activity. Surges are relevant as they disturb the link between glacier change and climate, and studying surges can also increase understanding of glacier flow. We use variations in Sentinel-1 radar backscatter strength, calculated with the use of Google Earth Engine, to detect surge activity. In our case study for the year 2018–2019 we find 69 cases of surging glaciers globally. Many of these were not previously known to be surging.
George Brencher, Alexander L. Handwerger, and Jeffrey S. Munroe
The Cryosphere, 15, 4823–4844, https://doi.org/10.5194/tc-15-4823-2021, https://doi.org/10.5194/tc-15-4823-2021, 2021
Short summary
Short summary
We use satellite InSAR to inventory and monitor rock glaciers, frozen bodies of ice and rock debris that are an important water resource in the Uinta Mountains, Utah, USA. Our inventory contains 205 rock glaciers, which occur within a narrow elevation band and deform at 1.94 cm yr-1 on average. Uinta rock glacier movement changes seasonally and appears to be driven by spring snowmelt. The role of rock glaciers as a perennial water resource is threatened by ice loss due to climate change.
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
Short summary
Short summary
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.
Corey Scher, Nicholas C. Steiner, and Kyle C. McDonald
The Cryosphere, 15, 4465–4482, https://doi.org/10.5194/tc-15-4465-2021, https://doi.org/10.5194/tc-15-4465-2021, 2021
Short summary
Short summary
Time series synthetic aperture radar enables detection of seasonal reach-scale glacier surface melting across continents, a key component of surface energy balance for mountain glaciers. We observe melting across all areas of the Hindu Kush Himalaya (HKH) cryosphere. Surface melting for the HKH lasts for close to 5 months per year on average and for just below 2 months at elevations exceeding 7000 m a.s.l. Further, there are indications that melting is more than superficial at high elevations.
Lander Van Tricht, Philippe Huybrechts, Jonas Van Breedam, Alexander Vanhulle, Kristof Van Oost, and Harry Zekollari
The Cryosphere, 15, 4445–4464, https://doi.org/10.5194/tc-15-4445-2021, https://doi.org/10.5194/tc-15-4445-2021, 2021
Short summary
Short summary
We conducted innovative research on the use of drones to determine the surface mass balance (SMB) of two glaciers. Considering appropriate spatial scales, we succeeded in determining the SMB in the ablation area with large accuracy. Consequently, we are convinced that our method and the use of drones to monitor the mass balance of a glacier’s ablation area can be an add-on to stake measurements in order to obtain a broader picture of the heterogeneity of the SMB of glaciers.
Yuting Dong, Ji Zhao, Dana Floricioiu, Lukas Krieger, Thomas Fritz, and Michael Eineder
The Cryosphere, 15, 4421–4443, https://doi.org/10.5194/tc-15-4421-2021, https://doi.org/10.5194/tc-15-4421-2021, 2021
Short summary
Short summary
We generated a consistent, gapless and high-resolution (12 m) topography product of the Antarctic Peninsula by combining the complementary advantages of the two most recent high-resolution digital elevation model (DEM) products: the TanDEM-X DEM and the Reference Elevation Model of Antarctica. The generated DEM maintains the characteristics of the TanDEM-X DEM, has a better quality due to the correction of the residual height errors in the non-edited TanDEM-X DEM and will be freely available.
Sergey Samsonov, Kristy Tiampo, and Ryan Cassotto
The Cryosphere, 15, 4221–4239, https://doi.org/10.5194/tc-15-4221-2021, https://doi.org/10.5194/tc-15-4221-2021, 2021
Short summary
Short summary
The direction and intensity of glacier surface flow adjust in response to a warming climate, causing sea level rise, seasonal flooding and droughts, and changing landscapes and habitats. We developed a technique that measures the evolution of surface flow for a glaciated region in three dimensions with high temporal and spatial resolution and used it to map the temporal evolution of glaciers in southeastern Alaska (Agassiz, Seward, Malaspina, Klutlan, Walsh, and Kluane) during 2016–2021.
Anne Braakmann-Folgmann, Andrew Shepherd, and Andy Ridout
The Cryosphere, 15, 3861–3876, https://doi.org/10.5194/tc-15-3861-2021, https://doi.org/10.5194/tc-15-3861-2021, 2021
Short summary
Short summary
We investigate the disintegration of the B30 iceberg using satellite remote sensing and find that the iceberg lost 378 km3 of ice in 6.5 years, corresponding to 80 % of its initial volume. About two thirds are due to fragmentation at the sides, and one third is due to melting at the iceberg’s base. The release of fresh water and nutrients impacts ocean circulation, sea ice formation, and biological production. We show that adding a snow layer is important when deriving iceberg thickness.
Joschka Geissler, Christoph Mayer, Juilson Jubanski, Ulrich Münzer, and Florian Siegert
The Cryosphere, 15, 3699–3717, https://doi.org/10.5194/tc-15-3699-2021, https://doi.org/10.5194/tc-15-3699-2021, 2021
Short summary
Short summary
The study demonstrates the potential of photogrammetry for analyzing glacier retreat with high spatial resolution. Twenty-three glaciers within the Ötztal Alps are analyzed. We compare photogrammetric and glaciologic mass balances of the Vernagtferner by using the ELA for our density assumption and an UAV survey for a temporal correction of the geodetic mass balances. The results reveal regions of anomalous mass balance and allow estimates of the imbalance between mass balances and ice dynamics.
Lukas Müller, Martin Horwath, Mirko Scheinert, Christoph Mayer, Benjamin Ebermann, Dana Floricioiu, Lukas Krieger, Ralf Rosenau, and Saurabh Vijay
The Cryosphere, 15, 3355–3375, https://doi.org/10.5194/tc-15-3355-2021, https://doi.org/10.5194/tc-15-3355-2021, 2021
Short summary
Short summary
Harald Moltke Bræ, a marine-terminating glacier in north-western Greenland, undergoes remarkable surges of episodic character. Our data show that a recent surge from 2013 to 2019 was initiated at the glacier front and exhibits a pronounced seasonality with flow velocities varying by 1 order of magnitude, which has not been observed at Harald Moltke Bræ in this way before. These findings are crucial for understanding surge mechanisms at Harald Moltke Bræ and other marine-terminating glaciers.
Joseph A. MacGregor, Michael Studinger, Emily Arnold, Carlton J. Leuschen, Fernando Rodríguez-Morales, and John D. Paden
The Cryosphere, 15, 2569–2574, https://doi.org/10.5194/tc-15-2569-2021, https://doi.org/10.5194/tc-15-2569-2021, 2021
Short summary
Short summary
We combine multiple recent global glacier datasets and extend one of them (GlaThiDa) to evaluate past performance of radar-sounding surveys of the thickness of Earth's temperate glaciers. An empirical envelope for radar performance as a function of center frequency is determined, its limitations are discussed and its relevance to future radar-sounder survey and system designs is considered.
Maximillian Van Wyk de Vries and Andrew D. Wickert
The Cryosphere, 15, 2115–2132, https://doi.org/10.5194/tc-15-2115-2021, https://doi.org/10.5194/tc-15-2115-2021, 2021
Short summary
Short summary
We can measure glacier flow and sliding velocity by tracking patterns on the ice surface in satellite images. The surface velocity of glaciers provides important information to support assessments of glacier response to climate change, to improve regional assessments of ice thickness, and to assist with glacier fieldwork. Our paper describes Glacier Image Velocimetry (GIV), a new, easy-to-use, and open-source toolbox for calculating high-resolution velocity time series for any glacier on earth.
Daniel Cheng, Wayne Hayes, Eric Larour, Yara Mohajerani, Michael Wood, Isabella Velicogna, and Eric Rignot
The Cryosphere, 15, 1663–1675, https://doi.org/10.5194/tc-15-1663-2021, https://doi.org/10.5194/tc-15-1663-2021, 2021
Short summary
Short summary
Tracking changes in Greenland's glaciers is important for understanding Earth's climate, but it is time consuming to do so by hand. We train a program, called CALFIN, to automatically track these changes with human levels of accuracy. CALFIN is a special type of program called a neural network. This method can be applied to other glaciers and eventually other tracking tasks. This will enhance our understanding of the Greenland Ice Sheet and permit better models of Earth's climate.
Andri Gunnarsson, Sigurdur M. Gardarsson, Finnur Pálsson, Tómas Jóhannesson, and Óli G. B. Sveinsson
The Cryosphere, 15, 547–570, https://doi.org/10.5194/tc-15-547-2021, https://doi.org/10.5194/tc-15-547-2021, 2021
Short summary
Short summary
Surface albedo quantifies the fraction of the sunlight reflected by the surface of the Earth. During the melt season in the Northern Hemisphere solar energy absorbed by snow- and ice-covered surfaces is mainly controlled by surface albedo. For Icelandic glaciers, air temperature and surface albedo are the dominating factors governing annual variability of glacier surface melt. Satellite data from the MODIS sensor are used to create a data set spanning the glacier melt season.
Bryan Riel, Brent Minchew, and Ian Joughin
The Cryosphere, 15, 407–429, https://doi.org/10.5194/tc-15-407-2021, https://doi.org/10.5194/tc-15-407-2021, 2021
Short summary
Short summary
The availability of large volumes of publicly available remote sensing data over terrestrial glaciers provides new opportunities for studying the response of glaciers to a changing climate. We present an efficient method for tracking changes in glacier speeds at high spatial and temporal resolutions from surface observations, demonstrating the recovery of traveling waves over Jakobshavn Isbræ, Greenland. Quantification of wave properties may ultimately enhance understanding of glacier dynamics.
Chad A. Greene, Alex S. Gardner, and Lauren C. Andrews
The Cryosphere, 14, 4365–4378, https://doi.org/10.5194/tc-14-4365-2020, https://doi.org/10.5194/tc-14-4365-2020, 2020
Short summary
Short summary
Seasonal variability is a fundamental characteristic of any Earth surface system, but we do not fully understand which of the world's glaciers speed up and slow down on an annual cycle. Such short-timescale accelerations may offer clues about how individual glaciers will respond to longer-term changes in climate, but understanding any behavior requires an ability to observe it. We describe how to use satellite image feature tracking to determine the magnitude and timing of seasonal ice dynamics.
Ellyn M. Enderlin and Timothy C. Bartholomaus
The Cryosphere, 14, 4121–4133, https://doi.org/10.5194/tc-14-4121-2020, https://doi.org/10.5194/tc-14-4121-2020, 2020
Short summary
Short summary
Accurate predictions of future changes in glacier flow require the realistic simulation of glacier terminus position change in numerical models. We use crevasse observations for 19 Greenland glaciers to explore whether the two commonly used crevasse depth models match observations. The models cannot reproduce spatial patterns, and we largely attribute discrepancies between modeled and observed depths to the models' inability to account for advection.
Angus J. Dowson, Pascal Sirguey, and Nicolas J. Cullen
The Cryosphere, 14, 3425–3448, https://doi.org/10.5194/tc-14-3425-2020, https://doi.org/10.5194/tc-14-3425-2020, 2020
Short summary
Short summary
Satellite observations over 19 years are used to characterise the spatial and temporal variability of surface albedo across the gardens of Eden and Allah, two of New Zealand’s largest ice fields. The variability in response of individual glaciers reveals the role of topographic setting and suggests that glaciers in the Southern Alps do not behave as a single climatic unit. There is evidence that the timing of the minimum surface albedo has shifted to later in the summer on 10 of the 12 glaciers.
Anna Bergstrom, Michael N. Gooseff, Madeline Myers, Peter T. Doran, and Julian M. Cross
The Cryosphere, 14, 769–788, https://doi.org/10.5194/tc-14-769-2020, https://doi.org/10.5194/tc-14-769-2020, 2020
Short summary
Short summary
This study sought to understand patterns of reflectance of visible light across the landscape of the McMurdo Dry Valleys, Antarctica. We used a helicopter-based platform to measure reflectance along an entire valley with a particular focus on the glaciers, as reflectance strongly controls glacier melt and available water to the downstream ecosystem. We found that patterns are controlled by gradients in snowfall, wind redistribution, and landscape structure, which can trap snow and sediment.
Désirée Treichler, Andreas Kääb, Nadine Salzmann, and Chong-Yu Xu
The Cryosphere, 13, 2977–3005, https://doi.org/10.5194/tc-13-2977-2019, https://doi.org/10.5194/tc-13-2977-2019, 2019
Short summary
Short summary
Glacier growth such as that found on the Tibetan Plateau (TP) is counterintuitive in a warming world. Climate models and meteorological data are conflicting about the reasons for this glacier anomaly. We quantify the glacier changes in High Mountain Asia using satellite laser altimetry as well as the growth of over 1300 inland lakes on the TP. Our study suggests that increased summer precipitation is likely the largest contributor to the recently observed increases in glacier and lake masses.
Christoph Rohner, David Small, Jan Beutel, Daniel Henke, Martin P. Lüthi, and Andreas Vieli
The Cryosphere, 13, 2953–2975, https://doi.org/10.5194/tc-13-2953-2019, https://doi.org/10.5194/tc-13-2953-2019, 2019
Short summary
Short summary
The recent increase in ice flow and calving rates of ocean–terminating glaciers contributes substantially to the mass loss of the Greenland Ice Sheet. Using in situ reference observations, we validate the satellite–based method of iterative offset tracking of Sentinel–1A data for deriving flow speeds. Our investigations highlight the importance of spatial resolution near the fast–flowing calving front, resulting in significantly higher ice velocities compared to large–scale operational products.
Jozef Šupinský, Ján Kaňuk, Zdenko Hochmuth, and Michal Gallay
The Cryosphere, 13, 2835–2851, https://doi.org/10.5194/tc-13-2835-2019, https://doi.org/10.5194/tc-13-2835-2019, 2019
Short summary
Short summary
Cave ice formations can be considered an indicator of long-term changes in the landscape. Using terrestrial laser scanning we generated a time series database of a 3-D cave model. We present a novel approach toward registration of scan missions into a unified coordinate system and methodology for detection of cave floor ice changes. We demonstrate the results of the ice dynamics monitoring correlated with meteorological observations in the Silická ľadnica cave situated in the Slovak Karst.
Thorsten Seehaus, Philipp Malz, Christian Sommer, Stefan Lippl, Alejo Cochachin, and Matthias Braun
The Cryosphere, 13, 2537–2556, https://doi.org/10.5194/tc-13-2537-2019, https://doi.org/10.5194/tc-13-2537-2019, 2019
Short summary
Short summary
The glaciers in Peru are strongly affected by climate change and have shown significant ice loss in the last century. We present the first multi-temporal, countrywide quantification of glacier area and ice mass changes. A glacier area loss of −548.5 ± 65.7 km2 (−29 %) and ice mass loss of −7.62 ± 1.05 Gt is obtained for the period 2000–2016. The ice loss rate increased towards the end of the observation period. The glacier changes revealed can be attributed to regional climatic changes and ENSO.
Dyre O. Dammann, Leif E. B. Eriksson, Son V. Nghiem, Erin C. Pettit, Nathan T. Kurtz, John G. Sonntag, Thomas E. Busche, Franz J. Meyer, and Andrew R. Mahoney
The Cryosphere, 13, 1861–1875, https://doi.org/10.5194/tc-13-1861-2019, https://doi.org/10.5194/tc-13-1861-2019, 2019
Short summary
Short summary
We validate TanDEM-X interferometry as a tool for deriving iceberg subaerial morphology using Operation IceBridge data. This approach enables a volumetric classification of icebergs, according to volume relevant to iceberg drift and decay, freshwater contribution, and potential impact on structures. We find iceberg volumes to generally match within 7 %. These results suggest that TanDEM-X could pave the way for future interferometric systems of scientific and operational iceberg classification.
Enze Zhang, Lin Liu, and Lingcao Huang
The Cryosphere, 13, 1729–1741, https://doi.org/10.5194/tc-13-1729-2019, https://doi.org/10.5194/tc-13-1729-2019, 2019
Short summary
Short summary
Conventionally, calving front positions have been manually delineated from remote sensing images. We design a novel method to automatically delineate the calving front positions of Jakobshavn Isbræ based on deep learning, the first of this kind for Greenland outlet glaciers. We generate high-temporal-resolution (about two measurements every month) calving fronts, demonstrating our methodology can be applied to many other tidewater glaciers through this successful case study on Jakobshavn Isbræ.
Robert McNabb, Christopher Nuth, Andreas Kääb, and Luc Girod
The Cryosphere, 13, 895–910, https://doi.org/10.5194/tc-13-895-2019, https://doi.org/10.5194/tc-13-895-2019, 2019
Short summary
Short summary
Estimating glacier changes involves measuring elevation changes, often using elevation models derived from satellites. Many elevation models have data gaps (voids), which affect estimates of glacier change. We compare 11 methods for interpolating voids, finding that some methods bias estimates of glacier change by up to 20 %, though most methods have a smaller effect. Some methods produce reliable results even with large void areas, suggesting that noisy elevation data are still useful.
Kathrin Naegeli, Matthias Huss, and Martin Hoelzle
The Cryosphere, 13, 397–412, https://doi.org/10.5194/tc-13-397-2019, https://doi.org/10.5194/tc-13-397-2019, 2019
Short summary
Short summary
The paper investigates the temporal changes of bare-ice glacier surface albedo in the Swiss Alps between 1999 and 2016 from a regional to local scale using satellite data. Significant negative trends were found in the lowermost elevations and margins of the ablation zones. Although significant changes of glacier ice albedo are only present over a limited area, we emphasize that albedo feedback will considerably enhance the rate of glacier mass loss in the Swiss Alps in the near future.
Mingyang Lv, Huadong Guo, Xiancai Lu, Guang Liu, Shiyong Yan, Zhixing Ruan, Yixing Ding, and Duncan J. Quincey
The Cryosphere, 13, 219–236, https://doi.org/10.5194/tc-13-219-2019, https://doi.org/10.5194/tc-13-219-2019, 2019
Short summary
Short summary
We highlight 28 glaciers in the Kingata Mountains, among which 17 have changed markedly over the last decade. We identify four advancing and 13 surge-type glaciers. The dynamic evolution of the surges is similar to that of Karakoram, suggesting that both hydrological and thermal controls are important for surge initiation and recession. Topography seems to be a dominant control on non-surge glacier behaviour. Most glaciers experienced a significant and diverse change in their motion patterns.
Sam Herreid and Francesca Pellicciotti
The Cryosphere, 12, 1811–1829, https://doi.org/10.5194/tc-12-1811-2018, https://doi.org/10.5194/tc-12-1811-2018, 2018
Short summary
Short summary
Ice cliffs are steep, bare ice features that can develop on the lower reaches of a glacier where the surface is covered by a layer of rock debris. Debris cover generally slows the rate of glacier melt, but ice cliffs act as small windows of higher rates of melt. It is therefore important to map these features, a process which we have automated. On a global scale, ice cliffs have variable geometries and characteristics. The method we have developed can accommodate this variability automatically.
Etienne Berthier, Christopher Larsen, William J. Durkin, Michael J. Willis, and Matthew E. Pritchard
The Cryosphere, 12, 1523–1530, https://doi.org/10.5194/tc-12-1523-2018, https://doi.org/10.5194/tc-12-1523-2018, 2018
Short summary
Short summary
Two recent studies suggested a slowdown in mass loss after 2000 of the Juneau and Stikine icefields, accounting for 10% of the total ice cover in Alaska. Here, the ASTER-based geodetic mass balances are revisited, carefully avoiding the use of the SRTM DEM, because of the unknown penetration depth of the SRTM C-band radar signal. We find strongly negative mass balances from 2000 to 2016 for both icefields, in agreement with airborne laser altimetry. Mass losses are thus continuing unabated.
Cited articles
Abe, T. and Furuya, M.: Winter speed-up of quiescent surge-type glaciers in
Yukon, Canada, The Cryosphere, 9, 1183–1190,
https://doi.org/10.5194/tc-9-1183-2015, 2015. a, b
Abe, T., Furuya, M., and Sakakibara, D.: Brief Communication: Twelve-year
cyclic surging episodes at Donjek Glacier in Yukon, Canada, The Cryosphere,
10, 1427–1432, https://doi.org/10.5194/tc-10-1427-2016, 2016. a, b
Altena, B. and Kääb, A.: Weekly glacier flow estimation from dense
satellite time series using adapted optical flow technology, Front.
Earth Sci., 5, 53 pp., https://doi.org/10.3389/feart.2017.00053, 2017b. a
Arendt, A., Luthcke, S., Gardner, A., O'neel, S., Hill, D., Moholdt, G., and
Abdalati, W.: Analysis of a GRACE global mascon solution for Gulf of
Alaska glaciers, J. Glaciol., 59, 913–924,
https://doi.org/10.3189/2013JoG12J197, 2013. a
Arendt, A. A.: Assessing the status of Alaska's glaciers, Science, 332,
1044–1045, https://doi.org/10.1126/science.1204400, 2011. a
Armstrong, W. H., Anderson, R. S., and Fahnestock, M. A.: Spatial patterns of
summer speedup on South central Alaska glaciers, Geophys. Res.
Lett., 44, 1–10, https://doi.org/10.1002/2017GL074370, 2017. a
Baarda, W.: A testing procedure for use in geodetic networks, vol. 2,
Publications on Geodesy, Rijkscommissie voor Geodesie, 1968. a
Berthier, E., Schiefer, E., Clarke, G. K., Menounos, B., and Rémy, F.:
Contribution of Alaskan glaciers to sea-level rise derived from satellite
imagery, Nat. Geosci., 3, 92–95, https://doi.org/10.1038/ngeo737, 2010. a
Bieniek, P. A., Bhatt, U. S., Thoman, R. L., Angeloff, H., Partain, J.,
Papineau, J., Fritsch, F., Holloway, E., Walsh, J. E., Daly, C., Shulski, M., Hufford, G., Hill, D. F., Calos, S., and Gens, R.:
Climate divisions for Alaska based on objective methods, J. Appl.
Meteorol. Clim., 51, 1276–1289, https://doi.org/10.1175/JAMC-D-11-0168.1,
2012. a
Burgess, E. W., Forster, R. R., Larsen, C. F., and Braun, M.: Surge dynamics
on Bering Glacier, Alaska, in 2008–2011, The Cryosphere, 6, 1251–1262,
https://doi.org/10.5194/tc-6-1251-2012, 2012. a, b
Burgess, E. W., Forster, R. R., and Larsen, C. F.: Flow velocities of Alaskan
glaciers, Nat. Commun., 4, 2146, https://doi.org/10.1038/ncomms3146, 2013. a
Clarke, G. K. and Holdsworth, G.: Glaciers of the St. Elias mountains, US
Geological Survey professional paper, in: Satellite Image Atlas of Glaciers of the World – North America, edited by: Williams, R. S. and Ferrigno, J. G.,
USGS Professional Paper 1386-J2002, 2002. a
Copland, L., Pope, S., Bishop, M. P., Shroder, J. F., Clendon, P., Bush, A.,
Kamp, U., Seong, Y. B., and Owen, L. A.: Glacier velocities across the
central Karakoram, Ann. Glaciol., 50, 41–49,
https://doi.org/10.3189/172756409789624229, 2009. a
Debella-Gilo, M. and Kääb, A.: Sub-pixel precision image matching for
measuring surface displacements on mass movements using normalized
cross-correlation, Remote Sens. Environ., 115, 130–142,
https://doi.org/10.1016/j.rse.2010.08.012, 2011. a
Dehecq, A., Gourmelen, N., and Trouvé, E.: Deriving large-scale glacier
velocities from a complete satellite archive: Application to the
Pamir–Karakoram–Himalaya, Remote Sens. Environ., 162, 55–66,
https://doi.org/10.1016/j.rse.2015.01.031, 2015. a, b, c, d
Fahnestock, M., Scambos, T., Moon, T., Gardner, A., Haran, T., and Klinger,
M.:
Rapid large-area mapping of ice flow using Landsat 8, Remote Sens. Environ., 185, 84–94, https://doi.org/10.1016/j.rse.2015.11.023, 2016. a, b, c, d
Fatland, D. R. and Lingle, C. S.: InSAR observations of the 1993–95
Bering
Glacier (Alaska, USA) surge and a surge hypothesis, J.
Glaciol., 48, 439–451, https://doi.org/10.3189/172756502781831296, 2002. a
Fischler, M. A. and Bolles, R. C.: Random sample consensus: a paradigm for
model fitting with applications to image analysis and automated cartography,
Commun. ACM, 24, 381–395, https://doi.org/10.1145/358669.358692, 1981. a
Garcia, D.: Robust smoothing of gridded data in one and higher dimensions
with missing values, Comput. Stat. Data An., 54, 1167–1178,
https://doi.org/10.1016/j.csda.2009.09.020, 2010. a
Han, J., Kóczy, L., and Poston, T.: Fuzzy Hough transform, Pattern
Recogn. Lett., 15, 649–658, https://doi.org/10.1016/0167-8655(94)90068-X, 1994. a
Harig, C. and Simons, F. J.: Ice mass loss in Greenland, the Gulf of Alaska,
and the Canadian Archipelago: Seasonal cycles and decadal trends, Geophys.
Res. Lett., 43, 3150–3159, https://doi.org/10.1002/2016GL067759, 2016. a
Heid, T. and Kääb, A.: Evaluation of existing image matching methods
for deriving glacier surface displacements globally from optical satellite
imagery, Remote Sens. Environ., 118, 339–355,
https://doi.org/10.1016/j.rse.2011.11.024, 2012a. a, b, c
Heid, T. and Kääb, A.: Repeat optical satellite images reveal widespread
and long term decrease in land-terminating glacier speeds, The Cryosphere, 6,
467–478, https://doi.org/10.5194/tc-6-467-2012, 2012b. a
Herreid, S. and Truffer, M.: Automated detection of unstable glacier flow and
a spectrum of speedup behavior in the Alaska Range, J. Geophys.
Res.-Earth, 121, 64–81, https://doi.org/10.1002/2015JF003502, 2016. a
Jeong, S., Howat, I. M., and Ahn, Y.: Improved multiple matching method for
observing glacier motion with repeat image feature tracking, IEEE
T. Geosci. Remote, 55, 2431–2441,
https://doi.org/10.1109/TGRS.2016.2643699, 2017. a
Kääb, A. and Vollmer, M.: Surface geometry, thickness changes and
flow
fields on creeping mountain permafrost: automatic extraction by digital image
analysis, Permafrost Periglac., 11, 315–326,
https://doi.org/10.1002/1099-1530(200012)11:4<315::AID-PPP365>3.0.CO;2-J, 2000. a
Kääb, A., Winsvold, S. H., Altena, B., Nuth, C., Nagler, T., and
Wuite,
J.: Glacier remote sensing using Sentinel-2. part I: Radiometric and
geometric performance, and application to ice velocity, Remote Sensing, 8,
598,
https://doi.org/10.3390/rs8070598, 2016. a
Kolaas, J.: Getting started with HydrolabPIV v1.0, Research report in
mechanics 2016:01, University of Oslo,
http://urn.nb.no/URN:NBN:no-53997 (last access: 26 February 2019),
2016. a
Maksymiuk, O., Mayer, C., and Stilla, U.: Velocity estimation of glaciers
with
physically-based spatial regularization. Experiments using satellite SAR
intensity images, Remote Sens. Environ., 172, 190–204,
https://doi.org/10.1016/j.rse.2015.11.007, 2016. a
Meier, M. F. and Post, A.: What are glacier surges?, Can. J. Earth
Sci., 6, 807–817, https://doi.org/10.1139/e69-081, 1969. a
Melkonian, A. K., Willis, M. J., and Pritchard, M. E.: Satellite-derived
volume
loss rates and glacier speeds for the Juneau Icefield, Alaska, J.
Glaciol., 60, 743–760, https://doi.org/10.3189/2014JoG13J181, 2014. a
Molnia, B. F.: Glaciers of Alaska, Alaska Geographic Society, USGS
Professional Paper 1386-K,
https://doi.org/10.3133/pp1386K, 2008. a
Moon, T., Joughin, I., Smith, B., Broeke, M. R., Berg, W. J., Noël, B.,
and
Usher, M.: Distinct patterns of seasonal Greenland glacier velocity,
Geophys. Res. Lett., 41, 7209–7216, https://doi.org/10.1002/2014GL061836,
2014. a
Muskett, R. R., Lingle, C. S., Tangborn, W. V., and Rabus, B. T.:
Multi-decadal
elevation changes on Bagley ice valley and Malaspina glacier, Alaska,
Geophys. Res. Lett., 30, 1857, https://doi.org/10.1029/2003GL017707, 2003. a
Paul, F., Bolch, T., Kääb, A., Nagler, T., Nuth, C., Scharrer, K.,
Shepherd, A., Strozzi, T., Ticconi, F., Bhambri, R., Berthier, E., Bevan, S., Gourmelen, N., Heid, T., Jeong, S., Kunz, M., Lauknes, T. R.,
Luckman, A., Boncori, J. P. M., Moholdt, G., Muir, A., Neelmeijer, J., Rankl, M., VanLooy, J., and Van Niel, T.: The glaciers
climate change initiative: Methods for creating glacier area, elevation
change and velocity products, Remote Sens. Environ., 162, 408–426,
https://doi.org/10.1016/j.rse.2013.07.043, 2015. a
Paul, F., Strozzi, T., Schellenberger, T., and Kääb, A.: The 2015
Surge
of Hispar glacier in the Karakoram, Remote Sensing, 9, 888,
https://doi.org/10.3390/rs9090888, 2017. a
Pfeffer, W. T., Arendt, A. A., Bliss, A., Bolch, T., Cogley, J. G., Gardner,
A. S., Hagen, J.-O., Hock, R., Kaser, G., Kienholz, C., Miles, E., Moholdt, G., Mölg, N., Paul, F., Radić, V., Rastner, P., Raup, B. R., Rich, J., Sharp, M. J.,
and the Randolph consortium: The
Randolph Glacier Inventory: a globally complete inventory of glaciers,
J. Glaciol., 60, 537–552, 2014. a, b
Post, A.: Distribution of surging glaciers in western North America, J.
Glaciol., 8, 229–240, https://doi.org/10.3189/S0022143000031221, 1969. a, b
Quincey, D., Braun, M., Glasser, N., Bishop, M., Hewitt, K., and Luckman, A.:
Karakoram glacier surge dynamics, Geophys. Res. Lett., 38, 504,
https://doi.org/10.1029/2011GL049004, 2011. a
Rosenau, R., Scheinert, M., and Dietrich, R.: A processing system to monitor
Greenland outlet glacier velocity variations at decadal and seasonal time
scales utilizing the Landsat imagery, Remote Sens. Environ., 169,
1–19, https://doi.org/10.1016/j.rse.2015.07.012, 2015. a
Rosenau, R., Scheinert, M., and Ebermann, B.: Velocity fields of Greenland
outlet glaciers, Technische Universität Dresden, Germany,
available at: http://data1.geo.tu-dresden.de/flow_velocity/ (last access: 26 February 2019),
2016. a
Rousseeuw, P. and Leroy, A.: Robust regression and outlier detection, vol.
589,
John wiley & sons, https://doi.org/10.1002/0471725382, 2005. a, b
Roy, D., Wulder, M., Loveland, T., Woodcock, C., Allen, R., Anderson, M.,
Helder, D., Irons, J., Johnson, D., Kennedy, R., Scambos, T., Schaaf, C.,
Schott, J., Sheng, Y., Vermote, E., Belward, A., Bindschadler, R., Cohen, W.,
Gao, F., Hipple, J., Hostert, P., Huntington, J., Justice, C., Kilic, A.,
Kovalskyy, V., Lee, Z., Lymburner, L., Masek, J., McCorkel, J., Shuai, Y.,
Trezza, R., Vogelmann, J., Wynne, R., and Zhu, Z.: Landsat-8: Science and
product vision for terrestrial global change research, Remote Sens.
Environ., 145, 154–172, https://doi.org/10.1016/j.rse.2014.02.001, 2014. a
Scambos, T., Dutkiewicz, M., Wilson, J., and Bindschadler, R.: Application of
image cross-correlation to the measurement of glacier velocity using
satellite image data, Remote Sens. Environ., 42, 177–186,
https://doi.org/10.1016/0034-4257(92)90101-O, 1992. a, b, c, d
Scambos, T., Fahnestock, M., Moon, T., Gardner, A., and Klinger, M.: Global
Land Ice Velocity Extraction from Landsat 8 (GoLIVE), Version 1, NSIDC:
National Snow and Ice Data Center, Boulder, Colorado USA,
https://doi.org/10.7265/N5ZP442B, http://nsidc.org/data/golive (last access: 26 February 2019),
2016. a, b, c
Scherler, D., Leprince, S., and Strecker, M. R.: Glacier-surface velocities
in
alpine terrain from optical satellite imagery – Accuracy improvement and
quality assessment, Remote Sens. Environ., 112, 3806–3819,
https://doi.org/10.1016/j.rse.2008.05.018, 2008. a
Skvarca, P.: Changes and surface features of the Larsen Ice Shelf,
Antarctica, derived from Landsat and Kosmos mosaics, Ann.
Glaciol., 20, 6–12, https://doi.org/10.3189/172756494794587140, 1994. a
Strang, G. and Borre, K.: Linear algebra, geodesy and GPS,
Wellesley-Cambridge
Press, 1997. a
Teunissen, P.: Testing theory, Series on Mathematical Geodesy and
Positioning,
Delft Academic Press, 2000. a
Turrin, J., Forster, R. R., Larsen, C., and Sauber, J.: The propagation of a
surge front on Bering glacier, Alaska, 2001–2011, Ann. Glaciol.,
54, 221–228, https://doi.org/10.3189/2013AoG63A341, 2013. a
Van Wychen, W., Copland, L., Jiskoot, H., Gray, L., Sharp, M., and Burgess,
D.:
Surface velocities of glaciers in Western Canada from speckle-tracking of
ALOS PALSAR and RADARSAT-2 data, Can. J. Remote Sens.,
44, 57–66, https://doi.org/10.1080/07038992.2018.1433529, 2018. a
Wackernagel, H.: Multivariate geostatistics: An introduction with
applications, Springer Science & Business Media,
https://doi.org/10.1007/978-3-662-05294-5, 2013.
a
Waechter, A., Copland, L., and Herdes, E.: Modern glacier velocities across
the
Icefield Ranges, St Elias Mountains, and variability at selected glaciers
from 1959 to 2012, J. Glaciol., 61, 624–634,
https://doi.org/10.3189/2015JoG14J147, 2015. a
Wang, D. and Kääb, A.: Modeling glacier elevation change from DEM
time
series, Remote Sensing, 7, 10117–10142, https://doi.org/10.3390/rs70810117, 2015. a
Westerweel, J. and Scarano, F.: Universal outlier detection for PIV data,
Exp. Fluids, 39, 1096–1100, https://doi.org/10.1007/s00348-005-0016-6, 2005. a
Short summary
Many glaciers in southern Alaska and the Yukon experience changes in flow speed, which occur in episodes or sporadically. These flow changes can be measured with satellites, but the resulting raw velocity products are messy. Thus in this study we developed an automatic method to produce a synthesized velocity product over a large glacier region of roughly 600 km by 200 km. Velocities are at a monthly resolution and at 300 m resolution, making all kinds of glacier dynamics observable.
Many glaciers in southern Alaska and the Yukon experience changes in flow speed, which occur in...
