First observations of sea ice flexural–gravity waves with ground-based radar interferometry in Utqiaġvik, Alaska

We investigate the application of ground-based radar interferometry for measuring flexural–gravity waves in sea ice. We deployed a GAMMA Portable Radar Interferometer (GPRI) on top of a grounded iceberg surrounded by landfast sea ice near Utqiaġvik, Alaska. The GPRI collected 238 acquisitions in sta...

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Bibliographic Details
Published in:The Cryosphere
Main Authors: Dammann, Dyre Oliver, Johnson, Mark A., Mahoney, Andrew R., Fedders, Emily R.
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2023
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Online Access:https://doi.org/10.5194/tc-17-1609-2023
https://noa.gwlb.de/receive/cop_mods_00065893
https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00064401/tc-17-1609-2023.pdf
https://tc.copernicus.org/articles/17/1609/2023/tc-17-1609-2023.pdf
Description
Summary:We investigate the application of ground-based radar interferometry for measuring flexural–gravity waves in sea ice. We deployed a GAMMA Portable Radar Interferometer (GPRI) on top of a grounded iceberg surrounded by landfast sea ice near Utqiaġvik, Alaska. The GPRI collected 238 acquisitions in stare mode during a period of moderate lateral ice motion during 23–24 April 2021. Individual 30 s interferograms exhibit ∼ 20–50 s periodic motion indicative of propagating infragravity waves with ∼ 1 mm amplitudes. Results include examples of onshore wave propagation at the speed predicted by the water depth and a possible edge wave along an ice discontinuity. Findings are supported through comparison with on-ice Ice Wave Rider (IWR) accelerometers and modeled wave propagation. These results suggest that the GPRI can be a valuable tool to track wave propagation through sea ice and possibly detect changes in such properties across variable ice conditions.