2019_programme: MODELING HIGH-FREQUENCY SCATTERING FROM SEA ICE

• Session: 09. Acoustics in polar environments
  Organiser(s): Tegowski Jaroslaw
• Lecture: MODELING HIGH-FREQUENCY SCATTERING FROM SEA ICE
  Paper ID: 908
  Author(s): Lyons Anthony, Deemer Gregory
  Presenter: Lyons Anthony
  Presentation type: oral
  Abstract: As sea ice evolves naturally through its growth and decay phases, so too does it manifest important changes in its internal microstructural elements which will affect its acoustic response. Variations in the porosity as well as distributions of gas bubbles and brine inclusions, lead to changes in scattered acoustic energy, and the efficiency of transmission into and attenuation within the ice. Knowledge of the seasonal variations of high-frequency scattering from the ice interface and volume over annual formation and melting cycles is essentially non-existent as only a limited number of measurements have been gathered. Owing to this lack of data, fundamental questions remain as to the dominant mechanisms influencing the under-ice acoustic scattering process at any given time. In this work, we will show modeling results for high-frequency acoustic scattering from first-year growing sea ice, highlighting the relative influence of various ice parameters on mean scattered levels and the dependence of these levels on frequency and grazing angle. Results yield insight into controlling factors and lead to recommendations for planned measurements over seasonal cycles from moored instruments and for analysis strategies for quantifying relevant sea-ice microstructure.
• Corresponding author: Dr Lyons Anthony
  Affiliation: University of New Hampshire
  Country: United States
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