Relating wave attenuation to pancake ice thickness, using field measurements and model results. Issue 11 (9th June 2015)

• Record Type: Journal Article
• Authors: Doble, Martin J.; De Carolis, Giacomo; Meylan, Michael H.; Bidlot, Jean‐Raymond; Wadhams, Peter
• Is Part Of: Geophysical research letters. Volume 42:Issue 11(2015:Jun.)
• Page Start: 4473
• Page End: 4481
• Publication Date: 2015-06-09
• Subjects: Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL063628
• Languages: English
• ISSNs: 0094-8276

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Wave attenuation coefficients (<italic>α</italic>, m⁻¹) were calculated from in situ data transmitted by custom wave buoys deployed into the advancing pancake ice region of the Weddell Sea. Data cover a 12 day period as the buoy array was first compressed and then dilated under the influence of a passing low‐pressure system. Attenuation was found to vary over more than 2 orders of magnitude and to be far higher than that observed in broken‐floe marginal ice zones. A clear linear relation between <italic>α</italic> and ice thickness was demonstrated, using ice thickness from a novel dynamic/thermodynamic model. A simple expression for <italic>α</italic> in terms of wave period and ice thickness was derived, for application in research and operational models. The variation of <italic>α</italic> was further investigated with a two‐layer viscous model, and a linear relation was found between eddy viscosity in the sub‐ice boundary layer and ice thickness.</p> </abstract>