Observations of Ocean Surface Wave Attenuation in Sea Ice Using Seafloor Cables

• Published in: Geophysical Research Letters
• Main Authors: Madison M. Smith, Jim Thomson, Michael G. Baker, Robert E. Abbott, Jake Davis
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2023
• Subjects: sea ice; waves; Arctic Ocean; coastal shelves; DAS; Geophysics. Cosmic physics; QC801-809; Sea ice; Alaska
• Online Access: https://doi.org/10.1029/2023GL105243; https://doaj.org/article/d4aee4a3e73f4c0c9906c2a4f0e769ed

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.