Buoy measurements of strong waves in ice amplitude modulation: a signature of the impact of sea ice closedness on waves in ice attenuation
Abstract. The Marginal Ice Zone (MIZ) forms a critical transition region between the ocean and sea ice cover, as it protects the close ice further in from the effect of the steepest and most energetic open ocean waves. As waves propagate through the MIZ, they become exponentially attenuated. Unfortunately, the associated attenuation coefficient is difficult to accurately estimate and model, and there are still large uncertainties around which attenuation mechanisms dominate depending on the conditions. This makes it difficult to predict waves in ice attenuation, as well as sea ice breakup and dynamics. Here, we report in situ observations of strongly modulated waves in ice amplitude, with a modulation period of around 12 h. We show that simple explanations, such as changes in the incoming open water waves or the direct effect of tides and currents and bathymetry on the propagating waves, cannot explain the observed modulation. Therefore, the wave height modulation observed in the ice comes from a modulation of the waves in ice attenuation coefficient. We gather evidence that sea ice convergence and divergence is likely the factor driving this modulation in the attenuation coefficient, through its influence on the ice “closedness”. This implies that the level of sea ice “closedness” needs to be taken into account by future dissipation parameterizations.
Authors
- Trygve K. Løken
- Alexander V. Babanin (ORCID: https://orcid.org/0000-0002-8595-8204)
- Konstantinos Christakos (ORCID: https://orcid.org/0000-0001-5615-9924)
- Takuji Waseda (ORCID: https://orcid.org/0000-0001-5403-5303)
- Jens Boldingh Debernard
- Sylvain Herlédan (ORCID: https://orcid.org/0000-0002-2322-9882)
- Anton Korosov (ORCID: https://orcid.org/0000-0002-3601-1161)
- Kai H. Christensen (ORCID: https://orcid.org/0000-0002-5775-794X)
- Tsubasa Kodaira (ORCID: https://orcid.org/0000-0003-4191-4362)
- Gaute Hope (ORCID: https://orcid.org/0000-0002-5653-1447)
- Cyril Palerme (ORCID: https://orcid.org/0000-0003-1475-7496)
- Trygve Halsne (ORCID: https://orcid.org/0000-0001-6675-2000)
- Joey Jeff Voermans (ORCID: https://orcid.org/0000-0002-2963-3763)
- Aleksey Marchenko (ORCID: https://orcid.org/0000-0003-4169-0063)
- Jean Rabault (ORCID: https://orcid.org/0000-0002-7244-6592)
- Lotfi Aouf (ORCID: https://orcid.org/0000-0002-0279-6773)
- Nick Hughes (ORCID: https://orcid.org/0000-0002-3510-0656)
- Atle Jensen (ORCID: https://orcid.org/0000-0001-7376-0850)
- Johannes Röhrs (ORCID: https://orcid.org/0000-0001-8402-2925)
- Graig Sutherland (ORCID: https://orcid.org/0000-0001-6109-9022)
- Malte Müller (ORCID: https://orcid.org/0000-0003-2871-8359)
- Ana Carrasco (ORCID: https://orcid.org/0000-0003-0410-933X)
- Øyvind Breivik (ORCID: https://orcid.org/0000-0002-2900-8458)
- Patrik Bohlinger (ORCID: https://orcid.org/0000-0002-7299-3676)
- Qin Zhang (ORCID: https://orcid.org/0000-0001-8356-4802)
- Lars Willas Dreyer (ORCID: https://orcid.org/0009-0001-1155-7889)
- Takehiko Nose
- Fabrice Collard (ORCID: https://orcid.org/0009-0008-3534-0511)
Institutions
- Centre National de la Recherche Scientifique (FR)
- Norwegian Meteorological Institute (NO)
- Environment and Climate Change Canada (CA)
- The University of Melbourne (AU)
- University of Oslo (NO)
- Nord University (NO)
- Météo-France (FR)
- Océanopolis (FR)
- Nansen Environmental and Remote Sensing Center (NO)
- University of Bergen (NO)
- The University of Tokyo (JP)
Publication Details
- Journal
- The cryosphere
- Published
- 2025-11-27
- DOI
- https://doi.org/10.5194/tc-19-6229-2025
- Primary Topic
- Arctic and Antarctic ice dynamics
- Type
- article
- Field-Weighted Citation Impact
- 0.00