Articles | Volume 18, issue 12
https://doi.org/10.5194/tc-18-5673-2024
© 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-18-5673-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Impacts of differing melt regimes on satellite radar waveforms and elevation retrievals
Alexander C. Ronan
CORRESPONDING AUTHOR
Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, United States
Robert L. Hawley
Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, United States
Jonathan W. Chipman
Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, United States
Department of Geography, Dartmouth College, Hanover, NH 03755, United States
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Derek J. Pickell, Robert L. Hawley, Denis Felikson, and Jamie C. Good
EGUsphere, https://doi.org/10.5194/egusphere-2025-2683, https://doi.org/10.5194/egusphere-2025-2683, 2025
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We compared satellite measurements of ice surface height in Greenland with ground-based observations, revealing sub-centimeter accuracy of the satellite instrument. We also demonstrated a new autonomous method using reflected radio signals to measure the surface without human traverses. This method produces comparable results, and we find no long-term changes in satellite performance to date.
Derek J. Pickell, Robert L. Hawley, and Adam LeWinter
The Cryosphere, 19, 1013–1029, https://doi.org/10.5194/tc-19-1013-2025, https://doi.org/10.5194/tc-19-1013-2025, 2025
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We use a low-cost, low-power GNSS network to measure surface accumulation in Greenland's interior using the interferometric reflectometry technique. Additionally, we extend this method to also estimate centimeter- to meter-scale surface roughness. Our results closely align with a validation record and highlight a period of unusually high accumulation from late 2022 to 2023, along with seasonal variations in surface roughness.
Ian A. Raphael, Donald K. Perovich, Christopher M. Polashenski, and Robert L. Hawley
EGUsphere, https://doi.org/10.5194/egusphere-2025-187, https://doi.org/10.5194/egusphere-2025-187, 2025
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Snow plays competing roles in the sea ice cycle by reflecting sunlight during summer (reducing melt) and insulating the ice from the cold atmosphere during winter (reducing growth). Observing where, when, and how much snow accumulates on sea ice is thus central to understanding the Arctic. Here, we describe a new snow depth observation system that is substantially cheaper and lighter than existing tools, and present a study demonstrating its potential to improve snow measurements on sea ice.
Ian E. McDowell, Kaitlin M. Keegan, S. McKenzie Skiles, Christopher P. Donahue, Erich C. Osterberg, Robert L. Hawley, and Hans-Peter Marshall
The Cryosphere, 18, 1925–1946, https://doi.org/10.5194/tc-18-1925-2024, https://doi.org/10.5194/tc-18-1925-2024, 2024
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Accurate knowledge of firn grain size is crucial for many ice sheet research applications. Unfortunately, collecting detailed measurements of firn grain size is difficult. We demonstrate that scanning firn cores with a near-infrared imager can quickly produce high-resolution maps of both grain size and ice layer distributions. We map grain size and ice layer stratigraphy in 14 firn cores from Greenland and document changes to grain size and ice layer content from the extreme melt summer of 2012.
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Short summary
We generate a 2010–2021 time series of CryoSat-2 waveform shape metrics on the Greenland Ice Sheet, and we compare it to CryoSat-2 elevation data to investigate the reliability of two algorithms used to derive elevations from the SIRAL radar altimeter. Retracked elevations are found to depend on a waveform's leading-edge width in the dry-snow zone. The study indicates that retracking algorithms must consider significant climate events and snow conditions when assessing elevation change.
We generate a 2010–2021 time series of CryoSat-2 waveform shape metrics on the Greenland Ice...