Luc Barast

Thesis topic: Interactions between near-surface turbulence and surface waves in the presence of sea ice

Advisors: Fabrice Ardhuin (director) and Peter Sutherland (co-director).
Funding: DGA (50%), IFREMER (50%)
2018-2023

Sea ice extent in the Arctic has been decreasing since the beginning of the satellite era, and the
resulting expanding area of open water is allowing the development of an increasingly important wave
climate. Waves affect ice creation and breakup, upper-ocean turbulence, and air-sea fluxes, meaning
that this new wave field introduces significant uncertainties to our understanding of Arctic Ocean
dynamics.
This thesis is part of ERC-WAAXT, which is a project designed to study the small scale processes that
are associated with this emerging wave field. I am participating in the BicWin series of field
campaigns, which investigate such physical processes in the Marginal Ice Zone of a natural laboratory
in the Lower St-Laurent Estuary (Canada). In particular, my role is to identify and study various
aspects of turbulence-wave-ice interactions, such as wave energy losses due to under-ice turbulence,
and wave-driven turbulence effects on ice melt/formation. I am approaching the problem using field
measurements, supported by modeling and theory, the long-term goal being to develop
parameterizations that can be used by the wave and upper-ocean modeling communities.
Keywords: MIZ, turbulence, sea-ice, air-sea interactions, BicWin, WAAXT