Modeling wave-ice interactions in the Gulf of St. Lawrence
Abstract
The Gulf of St. Lawrence (GSL) is a seasonally ice-covered basin located in eastern Canada that is subject to coastal erosion through the action of waves. Sea ice contributes in many ways to the prevailing wave conditions and to sediment transport at the coast. It reduces the fetch over which wind waves can grow and it selectively attenuates waves. Simulations of the future climate suggest that the maximum sea ice extent will decrease and that the winter season will shorten significantly, affecting the wave climate and the occurrence of extreme events. In this work we adapt and use a waves-in-ice model (WIM) to study how changing ice conditions will affect the wave conditions at the coast. WIM is an advection-attenuation model for waves propagating in sea ice that calculate the floe size distribution by way of floe breaking. It has been initially developed for swell waves impacting the arctic marginal ice zone (MIZ) and the generation of waves by the wind is not included. In order to simulate wave conditions in the GSL, wind wave generation is added to WIM and the wave spectrum at the coast is studied for various spatial distributions of sea ice and wind conditions. Obtained results are compared with observations from three acoustic wave and current (AWAC) profilers deployed in the GSL for three consecutive winters (2010-2013). This comparison allows us to assess the validity of the model and its parameterizations in seas that are covered with relatively thin ice and subject to modest wave conditions compared to the arctic MIZ.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFMOS11B1655B
- Keywords:
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- 4560 OCEANOGRAPHY: PHYSICAL Surface waves and tides;
- 4540 OCEANOGRAPHY: PHYSICAL Ice mechanics and air/sea/ice exchange processes;
- 4534 OCEANOGRAPHY: PHYSICAL Hydrodynamic modeling