Articles | Volume 18, issue 5
https://doi.org/10.5194/tc-18-2531-2024
© Author(s) 2024. 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-18-2531-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 May 2024
Research article |
| 23 May 2024
| 23 May 2024
Sentinel-1 detection of ice slabs on the Greenland Ice Sheet
Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, USA
Roger J. Michaelides
Department of Earth, Environmental, and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA
Julie Z. Miller
Earth Science and Observation Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, USA
Related authors
Kristian Chan, Cyril Grima, Anja Rutishauser, Duncan A. Young, Riley Culberg, and Donald D. Blankenship
The Cryosphere, 17, 1839–1852, https://doi.org/10.5194/tc-17-1839-2023, https://doi.org/10.5194/tc-17-1839-2023, 2023
Short summary
Short summary
Climate warming has led to more surface meltwater produced on glaciers that can refreeze in firn to form ice layers. Our work evaluates the use of dual-frequency ice-penetrating radar to characterize these ice layers on the Devon Ice Cap. Results indicate that they are meters thick and widespread, and thus capable of supporting lateral meltwater runoff from the top of ice layers. We find that some of this meltwater runoff could be routed through supraglacial rivers in the ablation zone.
Julie Z. Miller, Riley Culberg, David G. Long, Christopher A. Shuman, Dustin M. Schroeder, and Mary J. Brodzik
The Cryosphere, 16, 103–125, https://doi.org/10.5194/tc-16-103-2022, https://doi.org/10.5194/tc-16-103-2022, 2022
Short summary
Short summary
We use L-band brightness temperature imagery from NASA's Soil Moisture Active Passive (SMAP) satellite to map the extent of perennial firn aquifer and ice slab areas within the Greenland Ice Sheet. As Greenland's climate continues to warm and seasonal surface melting increases in extent, intensity, and duration, quantifying the possible rapid expansion of perennial firn aquifers and ice slab areas has significant implications for understanding the stability of the Greenland Ice Sheet.
Kristian Chan, Cyril Grima, Anja Rutishauser, Duncan A. Young, Riley Culberg, and Donald D. Blankenship
The Cryosphere, 17, 1839–1852, https://doi.org/10.5194/tc-17-1839-2023, https://doi.org/10.5194/tc-17-1839-2023, 2023
Short summary
Short summary
Climate warming has led to more surface meltwater produced on glaciers that can refreeze in firn to form ice layers. Our work evaluates the use of dual-frequency ice-penetrating radar to characterize these ice layers on the Devon Ice Cap. Results indicate that they are meters thick and widespread, and thus capable of supporting lateral meltwater runoff from the top of ice layers. We find that some of this meltwater runoff could be routed through supraglacial rivers in the ablation zone.
Julie Z. Miller, Riley Culberg, David G. Long, Christopher A. Shuman, Dustin M. Schroeder, and Mary J. Brodzik
The Cryosphere, 16, 103–125, https://doi.org/10.5194/tc-16-103-2022, https://doi.org/10.5194/tc-16-103-2022, 2022
Short summary
Short summary
We use L-band brightness temperature imagery from NASA's Soil Moisture Active Passive (SMAP) satellite to map the extent of perennial firn aquifer and ice slab areas within the Greenland Ice Sheet. As Greenland's climate continues to warm and seasonal surface melting increases in extent, intensity, and duration, quantifying the possible rapid expansion of perennial firn aquifers and ice slab areas has significant implications for understanding the stability of the Greenland Ice Sheet.
Seyedmohammad Mousavi, Andreas Colliander, Julie Z. Miller, and John S. Kimball
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-297, https://doi.org/10.5194/tc-2020-297, 2020
Manuscript not accepted for further review
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
Related subject area
Discipline: Ice sheets | Subject: Remote Sensing
Mapping the extent of giant Antarctic icebergs with deep learning
Mapping Antarctic crevasses and their evolution with deep learning applied to satellite radar imagery
AutoTerm: an automated pipeline for glacier terminus extraction using machine learning and a “big data” repository of Greenland glacier termini
Recent changes in drainage route and outburst magnitude of the Russell Glacier ice-dammed lake, West Greenland
Grounding line retreat and tide-modulated ocean channels at Moscow University and Totten Glacier ice shelves, East Antarctica
Seasonal land-ice-flow variability in the Antarctic Peninsula
Empirical correction of systematic orthorectification error in Sentinel-2 velocity fields for Greenlandic outlet glaciers
A leading-edge-based method for correction of slope-induced errors in ice-sheet heights derived from radar altimetry
An empirical algorithm to map perennial firn aquifers and ice slabs within the Greenland Ice Sheet using satellite L-band microwave radiometry
Supraglacial lake bathymetry automatically derived from ICESat-2 constraining lake depth estimates from multi-source satellite imagery
Penetration of interferometric radar signals in Antarctic snow
Brief communication: Ice sheet elevation measurements from the Sentinel-3A and Sentinel-3B tandem phase
Using ICESat-2 and Operation IceBridge altimetry for supraglacial lake depth retrievals
Brief communication: Mapping Greenland's perennial firn aquifers using enhanced-resolution L-band brightness temperature image time series
Quantifying spatiotemporal variability of glacier algal blooms and the impact on surface albedo in southwestern Greenland
Aerogeophysical characterization of an active subglacial lake system in the David Glacier catchment, Antarctica
Measuring the location and width of the Antarctic grounding zone using CryoSat-2
Brief Communication: Update on the GPS reflection technique for measuring snow accumulation in Greenland
Improved GNSS-R bi-static altimetry and independent digital elevation models of Greenland and Antarctica from TechDemoSat-1
Melt in Antarctica derived from Soil Moisture and Ocean Salinity (SMOS) observations at L band
Sentinel-3 Delay-Doppler altimetry over Antarctica
The Reference Elevation Model of Antarctica
Assessment of altimetry using ground-based GPS data from the 88S Traverse, Antarctica, in support of ICESat-2
Dual-satellite (Sentinel-2 and Landsat 8) remote sensing of supraglacial lakes in Greenland
Coherent large beamwidth processing of radio-echo sounding data
Multi-channel and multi-polarization radar measurements around the NEEM site
Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet
Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula
Anne Braakmann-Folgmann, Andrew Shepherd, David Hogg, and Ella Redmond
The Cryosphere, 17, 4675–4690, https://doi.org/10.5194/tc-17-4675-2023, https://doi.org/10.5194/tc-17-4675-2023, 2023
Short summary
Short summary
In this study, we propose a deep neural network to map the extent of giant Antarctic icebergs in Sentinel-1 images automatically. While each manual delineation requires several minutes, our U-net takes less than 0.01 s. In terms of accuracy, we find that U-net outperforms two standard segmentation techniques (Otsu, k-means) in most metrics and is more robust to challenging scenes with sea ice, coast and other icebergs. The absolute median deviation in iceberg area across 191 images is 4.1 %.
Trystan Surawy-Stepney, Anna E. Hogg, Stephen L. Cornford, and David C. Hogg
The Cryosphere, 17, 4421–4445, https://doi.org/10.5194/tc-17-4421-2023, https://doi.org/10.5194/tc-17-4421-2023, 2023
Short summary
Short summary
The presence of crevasses in Antarctica influences how the ice sheet behaves. It is important, therefore, to collect data on the spatial distribution of crevasses and how they are changing. We present a method of mapping crevasses from satellite radar imagery and apply it to 7.5 years of images, covering Antarctica's floating and grounded ice. We develop a method of measuring change in the density of crevasses and quantify increased fracturing in important parts of the West Antarctic Ice Sheet.
Enze Zhang, Ginny Catania, and Daniel T. Trugman
The Cryosphere, 17, 3485–3503, https://doi.org/10.5194/tc-17-3485-2023, https://doi.org/10.5194/tc-17-3485-2023, 2023
Short summary
Short summary
Glacier termini are essential for studying why glaciers retreat, but they need to be mapped automatically due to the volume of satellite images. Existing automated mapping methods have been limited due to limited automation, lack of quality control, and inadequacy in highly diverse terminus environments. We design a fully automated, deep-learning-based method to produce termini with quality control. We produced 278 239 termini in Greenland and provided a way to deliver new termini regularly.
Mads Dømgaard, Kristian K. Kjeldsen, Flora Huiban, Jonathan L. Carrivick, Shfaqat A. Khan, and Anders A. Bjørk
The Cryosphere, 17, 1373–1387, https://doi.org/10.5194/tc-17-1373-2023, https://doi.org/10.5194/tc-17-1373-2023, 2023
Short summary
Short summary
Sudden releases of meltwater from glacier-dammed lakes can influence ice flow, cause flooding hazards and landscape changes. This study presents a record of 14 drainages from 2007–2021 from a lake in west Greenland. The time series reveals how the lake fluctuates between releasing large and small amounts of drainage water which is caused by a weakening of the damming glacier following the large events. We also find a shift in the water drainage route which increases the risk of flooding hazards.
Tian Li, Geoffrey J. Dawson, Stephen J. Chuter, and Jonathan L. Bamber
The Cryosphere, 17, 1003–1022, https://doi.org/10.5194/tc-17-1003-2023, https://doi.org/10.5194/tc-17-1003-2023, 2023
Short summary
Short summary
The Totten and Moscow University glaciers in East Antarctica have the potential to make a significant contribution to future sea-level rise. We used a combination of different satellite measurements to show that the grounding lines have been retreating along the fast-flowing ice streams across these two glaciers. We also found two tide-modulated ocean channels that might open new pathways for the warm ocean water to enter the ice shelf cavity.
Karla Boxall, Frazer D. W. Christie, Ian C. Willis, Jan Wuite, and Thomas Nagler
The Cryosphere, 16, 3907–3932, https://doi.org/10.5194/tc-16-3907-2022, https://doi.org/10.5194/tc-16-3907-2022, 2022
Short summary
Short summary
Using high-spatial- and high-temporal-resolution satellite imagery, we provide the first evidence for seasonal flow variability of land ice draining to George VI Ice Shelf (GVIIS), Antarctica. Ultimately, our findings imply that other glaciers in Antarctica may be susceptible to – and/or currently undergoing – similar ice-flow seasonality, including at the highly vulnerable and rapidly retreating Pine Island and Thwaites glaciers.
Thomas R. Chudley, Ian M. Howat, Bidhyananda Yadav, and Myoung-Jong Noh
The Cryosphere, 16, 2629–2642, https://doi.org/10.5194/tc-16-2629-2022, https://doi.org/10.5194/tc-16-2629-2022, 2022
Short summary
Short summary
Sentinel-2 images are subject to distortion due to orthorectification error, which makes it difficult to extract reliable glacier velocity fields from images from different orbits. Here, we use a complete record of velocity fields at four Greenlandic outlet glaciers to empirically estimate the systematic error, allowing us to correct cross-track glacier velocity fields to a comparable accuracy to other medium-resolution satellite datasets.
Weiran Li, Cornelis Slobbe, and Stef Lhermitte
The Cryosphere, 16, 2225–2243, https://doi.org/10.5194/tc-16-2225-2022, https://doi.org/10.5194/tc-16-2225-2022, 2022
Short summary
Short summary
This study proposes a new method for correcting the slope-induced errors in satellite radar altimetry. The slope-induced errors can significantly affect the height estimations of ice sheets if left uncorrected. This study applies the method to radar altimetry data (CryoSat-2) and compares the performance with two existing methods. The performance is assessed by comparison with independent height measurements from ICESat-2. The assessment shows that the method performs promisingly.
Julie Z. Miller, Riley Culberg, David G. Long, Christopher A. Shuman, Dustin M. Schroeder, and Mary J. Brodzik
The Cryosphere, 16, 103–125, https://doi.org/10.5194/tc-16-103-2022, https://doi.org/10.5194/tc-16-103-2022, 2022
Short summary
Short summary
We use L-band brightness temperature imagery from NASA's Soil Moisture Active Passive (SMAP) satellite to map the extent of perennial firn aquifer and ice slab areas within the Greenland Ice Sheet. As Greenland's climate continues to warm and seasonal surface melting increases in extent, intensity, and duration, quantifying the possible rapid expansion of perennial firn aquifers and ice slab areas has significant implications for understanding the stability of the Greenland Ice Sheet.
Rajashree Tri Datta and Bert Wouters
The Cryosphere, 15, 5115–5132, https://doi.org/10.5194/tc-15-5115-2021, https://doi.org/10.5194/tc-15-5115-2021, 2021
Short summary
Short summary
The ICESat-2 laser altimeter can detect the surface and bottom of a supraglacial lake. We introduce the Watta algorithm, automatically calculating lake surface, corrected bottom, and (sub-)surface ice at high resolution adapting to signal strength. ICESat-2 depths constrain full lake depths of 46 lakes over Jakobshavn glacier using multiple sources of imagery, including very high-resolution Planet imagery, used for the first time to extract supraglacial lake depths empirically using ICESat-2.
Helmut Rott, Stefan Scheiblauer, Jan Wuite, Lukas Krieger, Dana Floricioiu, Paola Rizzoli, Ludivine Libert, and Thomas Nagler
The Cryosphere, 15, 4399–4419, https://doi.org/10.5194/tc-15-4399-2021, https://doi.org/10.5194/tc-15-4399-2021, 2021
Short summary
Short summary
We studied relations between interferometric synthetic aperture radar (InSAR) signals and snow–firn properties and tested procedures for correcting the penetration bias of InSAR digital elevation models at Union Glacier, Antarctica. The work is based on SAR data of the TanDEM-X mission, topographic data from optical sensors and field measurements. We provide new insights on radar signal interactions with polar snow and show the performance of penetration bias retrievals using InSAR coherence.
Malcolm McMillan, Alan Muir, and Craig Donlon
The Cryosphere, 15, 3129–3134, https://doi.org/10.5194/tc-15-3129-2021, https://doi.org/10.5194/tc-15-3129-2021, 2021
Short summary
Short summary
We evaluate the consistency of ice sheet elevation measurements made by two satellites: Sentinel-3A and Sentinel-3B. We analysed data from the unique
tandemphase of the mission, where the two satellites flew 30 s apart to provide near-instantaneous measurements of Earth's surface. Analysing these data over Antarctica, we find no significant difference between the satellites, which is important for demonstrating that they can be used interchangeably for long-term ice sheet monitoring.
Zachary Fair, Mark Flanner, Kelly M. Brunt, Helen Amanda Fricker, and Alex Gardner
The Cryosphere, 14, 4253–4263, https://doi.org/10.5194/tc-14-4253-2020, https://doi.org/10.5194/tc-14-4253-2020, 2020
Short summary
Short summary
Ice on glaciers and ice sheets may melt and pond on ice surfaces in summer months. Detection and observation of these meltwater ponds is important for understanding glaciers and ice sheets, and satellite imagery has been used in previous work. However, image-based methods struggle with deep water, so we used data from the Ice, Clouds, and land Elevation Satellite-2 (ICESat-2) and the Airborne Topographic Mapper (ATM) to demonstrate the potential for lidar depth monitoring.
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
Shujie Wang, Marco Tedesco, Patrick Alexander, Min Xu, and Xavier Fettweis
The Cryosphere, 14, 2687–2713, https://doi.org/10.5194/tc-14-2687-2020, https://doi.org/10.5194/tc-14-2687-2020, 2020
Short summary
Short summary
Glacial algal blooms play a significant role in darkening the Greenland Ice Sheet during summertime. The dark pigments generated by glacial algae could substantially reduce the bare ice albedo and thereby enhance surface melt. We used satellite data to map the spatial distribution of glacial algae and characterized the seasonal growth pattern and interannual trends of glacial algae in southwestern Greenland. Our study is important for bridging microbial activities with ice sheet mass balance.
Laura E. Lindzey, Lucas H. Beem, Duncan A. Young, Enrica Quartini, Donald D. Blankenship, Choon-Ki Lee, Won Sang Lee, Jong Ik Lee, and Joohan Lee
The Cryosphere, 14, 2217–2233, https://doi.org/10.5194/tc-14-2217-2020, https://doi.org/10.5194/tc-14-2217-2020, 2020
Short summary
Short summary
An extensive aerogeophysical survey including two active subglacial lakes was conducted over David Glacier, Antarctica. Laser altimetry shows that the lakes were at a highstand, while ice-penetrating radar has no unique signature for the lakes when compared to the broader basal environment. This suggests that active subglacial lakes are more likely to be part of a distributed subglacial hydrological system than to be discrete reservoirs, which has implications for future surveys and drilling.
Geoffrey J. Dawson and Jonathan L. Bamber
The Cryosphere, 14, 2071–2086, https://doi.org/10.5194/tc-14-2071-2020, https://doi.org/10.5194/tc-14-2071-2020, 2020
Short summary
Short summary
The grounding zone is where grounded ice begins to float and is the boundary at which the ocean has the most significant influence on the inland ice sheet. Here, we present the results of mapping the grounding zone of Antarctic ice shelves from CryoSat-2 radar altimetry. We found good agreement with previous methods that mapped the grounding zone. We also managed to map areas of Support Force Glacier and the Doake Ice Rumples (Filchner–Ronne Ice Shelf), which were previously incompletely mapped.
Kristine M. Larson, Michael MacFerrin, and Thomas Nylen
The Cryosphere, 14, 1985–1988, https://doi.org/10.5194/tc-14-1985-2020, https://doi.org/10.5194/tc-14-1985-2020, 2020
Short summary
Short summary
Reflected GPS signals can be used to measure snow accumulation. The GPS method is accurate and has a footprint that is larger than that of many other methods. This short note makes available 9 years of daily snow accumulation measurements from Greenland that were derived from reflected GPS signals. It also provides information about open-source software that the cryosphere community can use to analyze other datasets.
Jessica Cartwright, Christopher J. Banks, and Meric Srokosz
The Cryosphere, 14, 1909–1917, https://doi.org/10.5194/tc-14-1909-2020, https://doi.org/10.5194/tc-14-1909-2020, 2020
Short summary
Short summary
This study uses reflected GPS signals to measure ice at the South Pole itself for the first time. These measurements are essential to understand the interaction of the ice with the Earth’s physical systems. Orbital constraints mean that satellites are usually unable to measure in the vicinity of the South Pole itself. This is overcome here by using data obtained by UK TechDemoSat-1. Data are processed to obtain the height of glacial ice across the Greenland and Antarctic ice sheets.
Marion Leduc-Leballeur, Ghislain Picard, Giovanni Macelloni, Arnaud Mialon, and Yann H. Kerr
The Cryosphere, 14, 539–548, https://doi.org/10.5194/tc-14-539-2020, https://doi.org/10.5194/tc-14-539-2020, 2020
Short summary
Short summary
To study the coast and ice shelves affected by melt in Antarctica during the austral summer, we exploited the 1.4 GHz radiometric satellite observations. We showed that this frequency provides additional information on melt occurrence and on the location of the water in the snowpack compared to the 19 GHz observations. This opens an avenue for improving the melting season monitoring with a combination of both frequencies and exploring the possibility of deep-water detection in the snowpack.
Malcolm McMillan, Alan Muir, Andrew Shepherd, Roger Escolà, Mònica Roca, Jérémie Aublanc, Pierre Thibaut, Marco Restano, Américo Ambrozio, and Jérôme Benveniste
The Cryosphere, 13, 709–722, https://doi.org/10.5194/tc-13-709-2019, https://doi.org/10.5194/tc-13-709-2019, 2019
Short summary
Short summary
Melting of the Greenland and Antarctic ice sheets is one of the main causes of current sea level rise. Understanding ice sheet change requires large-scale systematic satellite monitoring programmes. This study provides the first assessment of a new long-term source of measurements, from Sentinel-3 satellite altimetry. We estimate the accuracy of Sentinel-3 across Antarctica, show that the satellite can detect regions that are rapidly losing ice, and identify signs of subglacial lake activity.
Ian M. Howat, Claire Porter, Benjamin E. Smith, Myoung-Jong Noh, and Paul Morin
The Cryosphere, 13, 665–674, https://doi.org/10.5194/tc-13-665-2019, https://doi.org/10.5194/tc-13-665-2019, 2019
Short summary
Short summary
The Reference Elevation Model of Antarctica (REMA) is the first continental-scale terrain map at less than 10 m resolution, and the first with a time stamp, enabling measurements of elevation change. REMA is constructed from over 300 000 individual stereoscopic elevation models (DEMs) extracted from submeter-resolution satellite imagery. REMA is vertically registered to satellite altimetry, resulting in errors of less than 1 m over most of its area and relative uncertainties of decimeters.
Kelly M. Brunt, Thomas A. Neumann, and Christopher F. Larsen
The Cryosphere, 13, 579–590, https://doi.org/10.5194/tc-13-579-2019, https://doi.org/10.5194/tc-13-579-2019, 2019
Short summary
Short summary
This paper provides an assessment of new GPS elevation data collected near the South Pole, Antarctica, that will ultimately be used for ICESat-2 satellite elevation data validation. Further, using the new ground-based GPS data, this paper provides an assessment of airborne lidar elevation data collected between 2014 and 2017, which will also be used for ICESat-2 data validation.
Andrew G. Williamson, Alison F. Banwell, Ian C. Willis, and Neil S. Arnold
The Cryosphere, 12, 3045–3065, https://doi.org/10.5194/tc-12-3045-2018, https://doi.org/10.5194/tc-12-3045-2018, 2018
Short summary
Short summary
A new approach is presented for automatically monitoring changes to area and volume of surface lakes on the Greenland Ice Sheet using Landsat 8 and Sentinel-2 satellite data. The dual-satellite record improves on previous work since it tracks changes to more lakes (including small ones), identifies more lake-drainage events, and has higher precision. The results also show that small lakes are important in ice-sheet hydrology as they route more surface run-off into the ice sheet than large lakes.
Anton Heister and Rolf Scheiber
The Cryosphere, 12, 2969–2979, https://doi.org/10.5194/tc-12-2969-2018, https://doi.org/10.5194/tc-12-2969-2018, 2018
Short summary
Short summary
We provide a method based on Fourier analysis of coherent radio-echo sounding data for analyzing angular back-scattering characteristics of the ice sheet and bed. The characteristics can be used for the bed roughness estimation and detection of subglacial water. The method also offers improved estimation of the internal layers' tilt. The research is motivated by a need for a tool for training dictionaries for model-based tomographic focusing of multichannel coherent radio-echo sounders.
Jilu Li, Jose A. Vélez González, Carl Leuschen, Ayyangar Harish, Prasad Gogineni, Maurine Montagnat, Ilka Weikusat, Fernando Rodriguez-Morales, and John Paden
The Cryosphere, 12, 2689–2705, https://doi.org/10.5194/tc-12-2689-2018, https://doi.org/10.5194/tc-12-2689-2018, 2018
Short summary
Short summary
Ice properties inferred from multi-polarization measurements can provide insight into ice strain, viscosity, and ice flow. The Center for Remote Sensing of Ice Sheets used a ground-based radar for multi-channel and multi-polarization measurements at the NEEM site. This paper describes the radar system, antenna configurations, data collection, and processing and analysis of this data set. Comparisons between the radar observations, simulations, and ice core fabric data are in very good agreement.
Fifi Ibrahime Adodo, Frédérique Remy, and Ghislain Picard
The Cryosphere, 12, 1767–1778, https://doi.org/10.5194/tc-12-1767-2018, https://doi.org/10.5194/tc-12-1767-2018, 2018
Short summary
Short summary
In Antarctica, the seasonal cycle of the backscatter behaves differently at high and low frequencies, peaking in winter and in summer, respectively. At the intermediate frequency, some areas behave analogously to low frequency in terms of the seasonal cycle, but other areas behave analogously to high frequency. This calls into question the empirical relationships often used to correct elevation changes from radar penetration into the snowpack using backscatter.
Peter Friedl, Thorsten C. Seehaus, Anja Wendt, Matthias H. Braun, and Kathrin Höppner
The Cryosphere, 12, 1347–1365, https://doi.org/10.5194/tc-12-1347-2018, https://doi.org/10.5194/tc-12-1347-2018, 2018
Short summary
Short summary
Fleming Glacier is the biggest tributary glacier of the former Wordie Ice Shelf. Radar satellite data and airborne ice elevation measurements show that the glacier accelerated by ~27 % between 2008–2011 and that ice thinning increased by ~70 %. This was likely a response to a two-phase ungrounding of the glacier tongue between 2008 and 2011, which was mainly triggered by increased basal melt during two strong upwelling events of warm circumpolar deep water.
Cited articles
Ashcraft, I. and Long, D.: Observation and Characterization of Radar Backscatter over Greenland, IEEE T. Geosci. Remote, 43, 225–237, https://doi.org/10.1109/TGRS.2004.841484, 2005. a
Ashcraft, I. S. and Long, D. G.: Comparison of Methods for Melt Detection over Greenland Using Active and Passive Microwave Measurements, Int. J. Remote Sens., 27, 2469–2488, https://doi.org/10.1080/01431160500534465, 2006. a
Bader, H.: Sorge's Law of Densification of Snow on High Polar Glaciers, J. Glaciol., 2, 319–323, https://doi.org/10.3189/S0022143000025144, 1954. a
Barzycka, B., Błaszczyk, M., Grabiec, M., and Jania, J.: Glacier Facies of Vestfonna (Svalbard) Based on SAR Images and GPR Measurements, Remote Sens. Environ., 221, 373–385, https://doi.org/10.1016/j.rse.2018.11.020, 2019. a, b, c, d
Baumgartner, F., Jezek, K. C., Forster, R. R., Gogineni, S. P., and Zabel, I. H. H.: Spectral and Angular Ground-Based Radar Backscatter Measurements of Greenland Snow Facies, in: 1999 IGARSS, Hamburg, Germany, 28 June–2 July 1999, Congress Centrum Hamburg, Hamburg, Germany, 614, https://doi.org/10.1109/IGARSS.1999.774530, pp. 1053–1055, 1999. a
Berger, M., Moreno, J., Johannessen, J. A., Levelt, P. F., and Hanssen, R. F.: ESA's sentinel missions in support of Earth system science, Remote Sens. Environ., 120, 84–90, 2012. a
Box, J. E., Wehrlé, A., van As, D., Fausto, R. S., Kjeldsen, K. K., Dachauer, A., Ahlstrøm, A. P., and Picard, G.: Greenland Ice Sheet Rainfall, Heat and Albedo Feedback Impacts From the Mid-August 2021 Atmospheric River, Geophys. Res. Lett., 49, e2021GL097356, https://doi.org/10.1029/2021GL097356, 2022. a
Box, J. E., Nielsen, K. P., Yang, X., Niwano, M., Wehrlé, A., van As, D., Fettweis, X., Køltzow, M. A. Ø., Palmason, B., Fausto, R. S., van den Broeke, M. R., Huai, B., Ahlstrøm, A. P., Langley, K., Dachauer, A., and Noël, B.: Greenland Ice Sheet Rainfall Climatology, Extremes and Atmospheric River Rapids, Meteorol. Appl., 30, e2134, https://doi.org/10.1002/met.2134, 2023. a, b
Brangers, I.: Firn aquifer map 1 kilometer (km) based on Sentinel-1 data, Greenland, 2014–2019, Arctic Data Center [data set], https://doi.org/10.18739/A2HD7NS8N, 2020. a
Brils, M., Kuipers Munneke, P., van de Berg, W. J., and van den Broeke, M.: Improved representation of the contemporary Greenland ice sheet firn layer by IMAU-FDM v1.2G, Geosci. Model Dev., 15, 7121–7138, https://doi.org/10.5194/gmd-15-7121-2022, 2022. a
Brils, M., Munneke, P. K., Jullien, N., Tedstone, A. J., Machguth, H., van de Berg, W. J., and van den Broeke, M. R.: Climatic Drivers of Ice Slabs and Firn Aquifers in Greenland, Geophys. Res. Lett., 51, e2023GL106613, https://doi.org/10.1029/2023GL106613, 2024. a, b, c
Culberg, R., Schroeder, D. M., and Chu, W.: Extreme Melt Season Ice Layers Reduce Firn Permeability across Greenland, Nat. Commun., 12, 1–9, https://doi.org/10.1038/s41467-021-22656-5, 2021. a, b
Culberg, R., Chu, W., and Schroeder, D. M.: Shallow Fracture Buffers High Elevation Runoff in Northwest Greenland, Geophys. Res. Lett., 49, e2022GL101151, https://doi.org/10.1029/2022GL101151, 2022. a, b
Culberg, R., Michaelides, R., and Miller, J. Z.: Supporting Data – Sentinel-1 Detection of Ice Slabs on the Greenland Ice Sheet (1.0.1), Zenodo [data set], https://doi.org/10.5281/zenodo.10892397, 2024. a
Dunmire, D., Banwell, A. F., Wever, N., Lenaerts, J. T. M., and Datta, R. T.: Contrasting regional variability of buried meltwater extent over 2 years across the Greenland Ice Sheet, The Cryosphere, 15, 2983–3005, https://doi.org/10.5194/tc-15-2983-2021, 2021. a
Enderlin, E., Howat, I., Jeong, S., Noh, M.-J., van Angelen, J. H., and van de Broeke, M. R.: An Improved Mass Budget for the Greenland Ice Sheet, Geophys. Res. Lett., 41, 866–872, https://doi.org/10.1002/2013GL059010, 2014. a
European Space Agency: Sentinel-1 SAR GRD: C-band Synthetic Aperture Radar Ground Range Detected, log scaling, Google Earth Engine [data set], https://developers.google.com/earth-engine/datasets/catalog/COPERNICUS_S1_GRD (last access: 8 November 2023), 2023, updated constantly. a
Fahnestock, M. A., Bindschadler, R., Kwok, R., and Jezek, K.: Greenland Ice Sheet Surface Properties and Ice Dynamics from ERS-1 SAR Imagery, Science, 262, 1530–1534, 1993. a
Fischer, G., Jäger, M., Papathanassiou, K. P., and Hajnsek, I.: Modeling the Vertical Backscattering Distribution in the Percolation Zone of the Greenland Ice Sheet With SAR Tomography, IEEE J. Sel. Top. Appl., 12, 4389–4405, https://doi.org/10.1109/JSTARS.2019.2951026, 2019. a
Forster, R. R., Box, J. E., Van Den Broeke, M. R., Miège, C., Burgess, E. W., Van Angelen, J. H., Lenaerts, J. T., Koenig, L. S., Paden, J., Lewis, C., Gogineni, S. P., Leuschen, C., and McConnell, J. R.: Extensive Liquid Meltwater Storage in Firn within the Greenland Ice Sheet, Nat. Geosci., 7, 95–98, https://doi.org/10.1038/ngeo2043, 2014. a
Fox-Kemper, B., Hewitt, H., Xiao, C., Aðalgeirsdóttir, G., Drijfhout, S. S., Edwards, T., Golledge, N., Hemer, M., Kopp, R., Krinner, G., Mix, A., Notz, D., Nowicki, S., Nurhati, I., Ruiz, L., Sallée, J.-B., Slangen, A., and Yu, Y.: Ocean, Cryosphere and Sea Level Change, in: Climate Change 2021: The Physical Science Basis, in: Intergovernmental Panel on Climate Change Sixth Assessment Report, chap. Chapter 9, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, https://doi.org/10.1017/9781009157896.011.1212, pp. 1211–1362, 2021. a, b
Gerrish, L.: The Coastline of Kalaallit Nunaat/Greenland Available as a Shapefile and Geopackage, Covering the Main Land and Islands, with Glacier Fronts Updated as of 2017, UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation [data set], https://doi.org/10.5285/8cecde06-8474-4b58-a9cb-b820fa4c9429, 2020. a, b, c, d, e, f
Gorelick, N., Hancher, M., Dixon, M., Ilyushchenko, S., Thau, D., and Moore, R.: Google Earth Engine: Planetary-scale Geospatial Analysis for Everyone, Remote Sens. Environ., 202, 18–27, https://doi.org/10.1016/j.rse.2017.06.031, 2017. a
Harper, J., Humphrey, N., Pfeffer, W. T., Brown, J., and Fettweis, X.: Greenland Ice-Sheet Contribution to Sea-Level Rise Buffered by Meltwater Storage in Firn, Nature, 491, 240–243, https://doi.org/10.1038/nature11566, 2012. a
Harper, J., Saito, J., and Humphrey, N.: Cold Season Rain Event Has Impact on Greenland's Firn Layer Comparable to Entire Summer Melt Season, Geophys. Res. Lett., 50, e2023GL103654, https://doi.org/10.1029/2023GL103654, 2023. a
Herron, M. M. and Langway, C. C.: Firn Densification: An Empirical Model, J. Glaciol., 25, 373–385, https://doi.org/10.3189/s0022143000015239, 1980. a
Hicks, B. R. and Long, D. G.: Inferring Greenland Melt and Refreeze Severity from SeaWinds Scatterometer Data, Int. J. Remote Sens., 32, 8053–8080, https://doi.org/10.1080/01431161.2010.532174, 2011. a
Hoen, W.: A Correlation-Based Approach to Modeling Interferometric Radar Observations of the Greenland Ice Sheet, Doctoral, Stanford University, Stanford, California, USA, 2001. a
Hu, J., Zhang, T., Zhou, X., Jiang, L., Yi, G., Wen, B., and Chen, Y.: Extracting Time-Series of Wet-Snow Facies in Greenland Using Sentinel-1 SAR Data on Google Earth Engine, IEEE J. Sel. Top. Appl., 15, 6190–6196, https://doi.org/10.1109/JSTARS.2022.3192409, 2022. a, b, c
Humphrey, N. F., Harper, J. T., and Pfeffer, W. T.: Thermal Tracking of Meltwater Retention in Greenland's Accumulation Area, J. Geophys. Res.-Earth, 117, 1–11, https://doi.org/10.1029/2011JF002083, 2012. a
Jezek, K. C., Drinkwater, M. R., Crawford, J. P., Bindschadler, R., and Kwok, R.: Analysis of Synthetic Aperture Radar Data Collected over the Southwestern Greenland Ice Sheet, J. Glaciol., 39, 119–132, https://doi.org/10.3189/S002214300001577X, 1993. a
Jezek, K. C., Gogineni, P., and Shanableh, M.: Radar Measurements of Melt Zones on the Greenland Ice Sheet, Geophys. Res. Lett., 21, 33–36, https://doi.org/10.1029/93GL03377, 1994. a, b
Koenig, L. S., Lampkin, D. J., Montgomery, L. N., Hamilton, S. L., Turrin, J. B., Joseph, C. A., Moutsafa, S. E., Panzer, B., Casey, K. A., Paden, J. D., Leuschen, C., and Gogineni, P.: Wintertime storage of water in buried supraglacial lakes across the Greenland Ice Sheet, The Cryosphere, 9, 1333–1342, https://doi.org/10.5194/tc-9-1333-2015, 2015. a
Langley, K., Hamran, S. E., Høgda, K. A., Storvold, R., Brandt, O., Hagen, J. O., and Kohler, J.: Use of C-band Ground Penetrating Radar to Determine Backscatter Sources within Glaciers, IEEE T. Geosci. Remote, 45, 1236–1245, https://doi.org/10.1109/TGRS.2007.892600, 2007. a, b, c
Langley, K., Hamran, S.-E., Hogda, K. A., Storvold, R., Brandt, O., Kohler, J., and Hagen, J. O.: From Glacier Facies to SAR Backscatter Zones via GPR, IEEE T. Geosci. Remote, 46, 2506–2516, https://doi.org/10.1109/TGRS.2008.918648, 2008. a, b
Langley, K., Lacroix, P., Hamran, S. E., and Brandt, O.: Sources of Backscatter at 5.3 GHz from a Superimposed Ice and Firn Area Revealed by Multi-Frequency GPR and Cores, J. Glaciol., 55, 373–383, https://doi.org/10.3189/002214309788608660, 2009. a, b, c, d
Li, G., Chen, X., Lin, H., Hooper, A., Chen, Z., and Cheng, X.: Glacier Melt Detection at Different Sites of Greenland Ice Sheet Using Dual-Polarized Sentinel-1 Images, Geo-spatial Information Science, 0, 1–16, https://doi.org/10.1080/10095020.2023.2252034, 2023. a
Liang, D., Guo, H., Zhang, L., Cheng, Y., Zhu, Q., and Liu, X.: Time-Series Snowmelt Detection over the Antarctic Using Sentinel-1 SAR Images on Google Earth Engine, Remote Sens. Environ., 256, 112318, https://doi.org/10.1016/j.rse.2021.112318, 2021. a
Lindsley, R. D. and Long, D. G.: ASCAT and QuikSCAT Azimuth Modulation of Backscatter Over East Antarctica, IEEE Geosci. Remote S., 13, 1134–1138, https://doi.org/10.1109/LGRS.2016.2572101, 2016. a
Long, D. G. and Drinkwater, M. R.: Greenland Ice-Sheet Surface Properties Observed by the Seasat-A Scatterometer at Enhanced Resolution, J. Glaciol., 40, 213–230, https://doi.org/10.3189/S0022143000007310, 1994. a, b
Long, D. G. and Miller, J. Z.: Validation of the Effective Resolution of SMAP Enhanced Resolution Backscatter Products, IEEE J. Sel. Top. Appl., 16, 3390–3404, https://doi.org/10.1109/JSTARS.2023.3260726, 2023. a
MacFerrin, M. J., Machguth, H., van As, D., Charalampidis, C., Stevens, C. M., Heilig, A., Vandecrux, B., Langen, P. L., Mottram, R. H., Fettweis, X., van den Broeke, M. R., Pfeffer, W. T., Moussavi, M., and Abdalati, W.: Rapid Expansion of Greenland's Low-Permeability Ice Slabs, Nature, 573, 403–407, https://doi.org/10.1038/s41586-019-1550-3, 2019. a, b, c, d, e, f, g, h
Machguth, H., Macferrin, M., Van As, D., Box, J. E., Charalampidis, C., Colgan, W., Fausto, R. S., Meijer, H. A., Mosley-Thompson, E., and Van De Wal, R. S.: Greenland Meltwater Storage in Firn Limited by Near-Surface Ice Formation, Nat. Clim. Change, 6, 390–393, https://doi.org/10.1038/nclimate2899, 2016. a, b, c, d
Marsh, P. and Woo, M.-K.: Wetting Front Advance and Freezing of Meltwater within a Snow Cover: 1. Observations in the Canadian Arctic, Water Resour. Res., 20, 1853–1864, https://doi.org/10.1029/WR020i012p01853, 1984. a
Miller, J. Z.: SMAP-derived Perennial Firn Aquifer and Ice Slab Extents 2015-2019, Zenodo [data set], https://doi.org/10.5281/zenodo.8380493, 2021. a, b
Miller, J. Z., Culberg, R., Long, D. G., Shuman, C. A., Schroeder, D. M., and Brodzik, M. J.: An empirical algorithm to map perennial firn aquifers and ice slabs within the Greenland Ice Sheet using satellite L-band microwave radiometry, The Cryosphere, 16, 103–125, https://doi.org/10.5194/tc-16-103-2022, 2022a. a, b, c, d, e, f, g
Miller, J. Z., Long, D. G., Shuman, C. A., Culberg, R., Hardman, M. A., and Brodzik, M. J.: Mapping Firn Saturation Over Greenland Using NASA's Soil Moisture Active Passive Satellite, IEEE J. Sel. Top. Appl., 15, 3714–3729, https://doi.org/10.1109/JSTARS.2022.3154968, 2022b. a, b
Morlighem, M., Williams, C. N., Rignot, E., An, L., Arndt, J. E., Bamber, J. L., Catania, G., Chauche, N., Dowdeswell, J. A., Dorschel, B., Fenty, I., Hogan, K., Howat, I., Hubbard, A., Jakobsson, M., Jordan, T. M., Kjeldsen, K. K., Millian, R., Mayer, L., Mouginto, J., Noel, B. P. Y., O'Cofaigh, C., Palmer, S., Rysgaard, S., Seroussi, H., Siegert, M. J., Slabon, P., Straneo, F., van den Broeke, M. R., Weinrebe, W., Wood, M., Zinglersen, K. B., Chauché, N., Dowdeswell, J. A., Dorschel, B., Fenty, I., Hogan, K., Howat, I., Hubbard, A., Jakobsson, M., Jordan, T. M., Kjeldsen, K. K., Millan, R., Mayer, L., Mouginot, J., Noël, B. P., O'Cofaigh, C., Palmer, S., Rysgaard, S., Seroussi, H., Siegert, M. J., Slabon, P., Straneo, F., van den Broeke, M. R., Weinrebe, W., Wood, M., and Zinglersen, K. B.: BedMachine v3: Complete Bed Topography and Ocean Bathymetry Mapping of Greenland From Multibeam Echo Sounding Combined With Mass Conservation, Geophys. Res. Lett., 44, 11051–11061, https://doi.org/10.1002/2017GL074954, 2017 (data available at: https://sites.ps.uci.edu/morlighem/dataproducts/bedmachine-greenland/, last access: 8 November 2023). a, b, c, d, e, f, g
Mouginot, J., Rignot, E., Bjørk, A. A., van den Broeke, M., Millan, R., Morlighem, M., Noël, B., Scheuchl, B., and Wood, M.: Forty-Six Years of Greenland Ice Sheet Mass Balance from 1972 to 2018, P. Natl. Acad. Sci. USA, 116, 9239–9244, https://doi.org/10.1073/pnas.1904242116, 2019. a
Munneke, P. K., M. Ligtenberg, S. R., van den Broeke, M. R., van Angelen, J. H., and Forster, R. R.: Explaining the Presence of Perennial Liquid Water Bodies in the Firn of the Greenland Ice Sheet, Geophys. Res. Lett., 41, 476–483, https://doi.org/10.1002/2013GL058389, 2014. a
Nagler, T. and Rott, H.: Retrieval of Wet Snow by Means of Multitemporal SAR Data, IEEE T. Geosci. Remote, 38, 754–765, https://doi.org/10.1109/36.842004, 2000. a
Noël, B., van de Berg, W. J., Lhermitte, S., and van den Broeke, M. R.: Rapid Ablation Zone Expansion Amplifies North Greenland Mass Loss, Science Advances, 5, 2–11, https://doi.org/10.1126/sciadv.aaw0123, 2019. a
Paden, J., Li, J., Rodriguez-Morales, F., and Hale, R.: IceBridge MCoRDS Radar L1B Geolocated Radar Echo Strength Profiles, Version 2 [2015_Greenland_C130], National Snow and Ice Data Center [data set], https://doi.org/10.5067/90S1XZRBAX5N, 2014a. a, b
Paden, J., Li, J., Rodriguez-Morales, F., and Hale, R.: IceBridge Accumulation Radar L1B Geolocated Radar Echo Strength Profiles, Version 2 [2017_Greenland_P3], National Snow and Ice Data Center [data set], https://doi.org/10.5067/0ZY1XYHNIQNY, 2014b. a, b
Partington, K. C.: Discrimination of Glacier Facies Using Multi-Temporal SAR Data, J. Glaciol., 44, 42–53, https://doi.org/10.3189/S0022143000002331, 1998. a
Pfeffer, W. T. and Humphrey, N. F.: Formation of Ice Layers by Infiltration and Refreezing of Meltwater, Ann. Glaciol., 26, 83–91, https://doi.org/10.3189/1998aog26-1-83-91, 1998. a
Porter, C., Morin, P., Howat, I., Noh, M., Bates, B., Peterman, K., Keesey, S., Schlenk, M., Gardiner, J., Tomko, K., Willis, M., Kelleher, C., Cloutier, M., Husby, E., Foga, S., Nakamura, H., Platson, M., Wethington Jr., M., Williamson, C., Bauer, G., Enos, J., Arnold, G., Kramer, W., Becker, P., Doshi, A., D'Souza, C., Cummens, P., Laurier, F., and Bojesen, M.: ArcticDEM, Version 3, Harvard Dataverse [data set], https://doi.org/10.7910/DVN/OHHUKH, 2018. a, b, c, d
Rignot, E., Echelmeyer, K., and Krabill, W.: Penetration Depth of Interferometric Synthetic-Aperture Radar Signals in Snow and Ice, Geophys. Res. Lett., 28, 3501–3504, https://doi.org/10.1029/2000GL012484, 2001. a
Rignot, E. J., Ostro, S. J., van Zyl, J. J., and Jezek, K. C.: Unusual Radar Echoes from the Greenland Ice Sheet, Science, 261, 1710–1713, https://doi.org/10.1126/science.261.5129.1710, 1993. a
Rizzoli, P., Martone, M., Rott, H., and Moreira, A.: Characterization of Snow Facies on the Greenland Ice Sheet Observed by TanDEM-X Interferometric SAR Data, Remote Sens.-Basel, 9, 315, https://doi.org/10.3390/rs9040315, 2017. a
Ryan, J. C., Smith, L. C., Van As, D., Cooley, S. W., Cooper, M. G., Pitcher, L. H., and Hubbard, A.: Greenland Ice Sheet Surface Melt Amplified by Snowline Migration and Bare Ice Exposure, Science Advances, 5, 1–11, https://doi.org/10.1126/sciadv.aav3738, 2019. a, b, c, d
Swift, C. T., Hayes, P. S., Herd, J. S., Jones, W. L., and Delnore, V. E.: Airborne Microwave Measurements of the Southern Greenland Ice Sheet, J. Geophys. Res.-Sol. Ea., 90, 1983–1994, https://doi.org/10.1029/JB090iB02p01983, 1985. a
Tedesco, M. and Fettweis, X.: Unprecedented atmospheric conditions (1948–2019) drive the 2019 exceptional melting season over the Greenland ice sheet, The Cryosphere, 14, 1209–1223, https://doi.org/10.5194/tc-14-1209-2020, 2020. a
Tedstone, A.: Increasing Surface Runoff from Greenland's Firn Areas, Zenodo [data set], https://doi.org/10.5281/zenodo.6472348, 2022. a, b, c
Tedstone, A. J. and Machguth, H.: Increasing Surface Runoff from Greenland's Firn Areas, Nat. Clim. Change, 12, 672–676, https://doi.org/10.1038/s41558-022-01371-z, 2022. a, b, c, d
Ulaby, F. T. and Long, D. G.: Microwave Radar and Radiometric Remote Sensing, The University of Michigan Press, Ann Arbor, MI, ISBN-13 978-0472119356, 2014. a
Van Den Broeke, M., Bamber, J., Ettema, J., Rignot, E., Schrama, E., Van Berg, W. J. D., Van Meijgaard, E., Velicogna, I., and Wouters, B.: Partitioning Recent Greenland Mass Loss, Science, 326, 984–986, https://doi.org/10.1126/science.1178176, 2009. a
Vollrath, A., Mullissa, A., and Reiche, J.: Angular-Based Radiometric Slope Correction for Sentinel-1 on Google Earth Engine, Remote Sens., 12, 1867, https://doi.org/10.3390/rs12111867, 2020. a
Wismann, V.: Monitoring of Seasonal Snowmelt on Greenland with ERS Scatterometer Data, IEEE T. Geosci. Remote, 38, 1821–1826, https://doi.org/10.1109/36.851766, 2000. a
Short summary
Ice slabs enhance meltwater runoff from the Greenland Ice Sheet. Therefore, it is important to understand their extent and change in extent over time. We present a new method for detecting ice slabs in satellite radar data, which we use to map ice slabs at 500 m resolution across the entire ice sheet in winter 2016–2017. Our results provide better spatial coverage and resolution than previous maps from airborne radar and lay the groundwork for long-term monitoring of ice slabs from space.
Ice slabs enhance meltwater runoff from the Greenland Ice Sheet. Therefore, it is important to...
