Modelling attenuation of irregular wave fields by artificial ice floes in the laboratory

A summary is given on the utility of laboratory experiments for gaining understanding of wave attenuation in the marginal ice zone, as a complement to field observations, theory and numerical models. It is noted that most results to date are for regular incident waves, which, combined with the highly nonlinear wave-floe interaction phenomena observed and measured during experimental tests, implies that the attenuation of regular waves cannot necessarily be used to infer the attenuation of irregular waves. Two experiments are revisited in which irregular wave tests were conducted but not previously reported, one involving a single floe and the other a large number of floes, and the transmission coefficients for the irregular and regular wave tests are compared. The transmission spectra derived from the irregular wave tests agree with the regular wave data but are overpredicted by linear models due to nonlinear dissipative processes, regardless of floe configuration.This article is part of the theme issue 'Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks'.

Automated summary

This article discusses the utility of laboratory experiments for understanding wave attenuation in the marginal ice zone. It highlights the limitations of using results from regular wave tests to infer the attenuation of irregular waves, due to the highly nonlinear wave-floe interaction phenomena observed during experimental tests. The article presents two previously unreported experiments involving irregular wave tests and compares the transmission coefficients with regular wave tests. The results indicate that linear models overpredict the transmission spectra of irregular waves due to nonlinear dissipative processes.