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This dataset contains processed ocean surface gravity wave parameters derived from interrogation of a seafloor fiber with distributed acoustic sensing (DAS). These measurements were taken on a fiber within a cable owned by Quintillion extending off the coast near Oliktok Point, Alaska in November 2021 and August 2022. Processing includes calculation of frequency-dependent, channel-specific correction factors using collocated wave buoy (SWIFT) observations, which is then multiplied by the PSD of raw strain-rate. A depth-attenuation correction is then also applied. Dataset includes the raw strain-rate spectra and the derived wave spectra, as well as bulk wave parameters including significant wave height (Hs), peak wave period (Tp), and energy-weighted wave period (Te).
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Observations of Ocean Surface Wave Attenuation in Sea Ice Using Seafloor Cables
Abstract The attenuation of ocean surface waves during seasonal ice cover is an important control on the evolution of Arctic coastlines. The spatial and temporal variations in this process have been challenging to resolve with conventional sampling using sparse arrays of moorings or buoys. We demonstrate a novel method for persistent observation of wave‐ice interactions using distributed acoustic sensing (DAS) along existing seafloor fiber optic telecommunications cables. DAS measurements span a 36‐km cross‐shore cable on the Beaufort Shelf from Oliktok Point, Alaska. DAS optical sensing of fiber strain‐rate provides a proxy for seafloor pressure, which we calibrate with wave buoy measurements during the ice‐free season (August 2022). We apply this calibration during the ice formation season (November 2021) to obtain unprecedented resolution of variable wave attenuation rates in new, partial ice cover. The location and strength of wave attenuation serve as proxies for ice coverage and thickness, especially during rapidly evolving events.
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- Award ID(s):
- 2214651
- PAR ID:
- 10471983
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 50
- Issue:
- 20
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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This dataset contains processed ocean surface gravity wave parameters derived from interrogation of a seafloor fiber with distributed acoustic sensing (DAS). These measurements were taken on a fiber within a cable owned by Quintillion extending off the coast near Oliktok Point, Alaska in November 2021 and August 2022. Processing includes calculation of frequency-dependent, channel-specific correction factors using collocated wave buoy (SWIFT) observations, which is then multiplied by the PSD of raw strain-rate. A depth-attenuation correction is then also applied. Dataset includes the raw strain-rate spectra and the derived wave spectra, as well as bulk wave parameters including significant wave height (Hs), peak wave period (Tp), and energy-weighted wave period (Te).more » « less
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