Annals of Glaciology (Sep 2020)

Observations of exponential wave attenuation in Antarctic sea ice during the PIPERS campaign

  • Alison L. Kohout,
  • Madison Smith,
  • Lettie A. Roach,
  • Guy Williams,
  • Fabien Montiel,
  • Michael J. M. Williams

DOI
https://doi.org/10.1017/aog.2020.36
Journal volume & issue
Vol. 61
pp. 196 – 209

Abstract

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Quantifying the rate of wave attenuation in sea ice is key to understanding trends in the Antarctic marginal ice zone extent. However, a paucity of observations of waves in sea ice limits progress on this front. We deployed 14 waves-in-ice observation systems (WIIOS) on Antarctic sea ice during the Polynyas, Ice Production, and seasonal Evolution in the Ross Sea expedition (PIPERS) in 2017. The WIIOS provide in situ measurement of surface wave characteristics. Two experiments were conducted, one while the ship was inbound and one outbound. The sea ice throughout the experiments generally consisted of pancake and young ice <0.5 m thick. The WIIOS survived a minimum of 4 d and a maximum of 6 weeks. Several large-wave events were captured, with the largest recorded significant wave height over 9 m. We find that the total wave energy measured by the WIIOS generally decays exponentially in the ice and the rate of decay depends on ice concentration.

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