title: Elastic parabolic equation and normal mode solutions for seismo-acoustic propagation in underwater environments with ice covers.
abstract: Sound propagation predictions for ice-covered ocean acoustic environments do not match observational data: received levels in nature are less than expected, suggesting that the effects of the ice are substantial. Effects due to elasticity in overlying ice can be significant enough that low-shear approximations, such as effective complex density treatments, may not be appropriate. Building on recent elastic seafloor modeling developments, a range-dependent parabolic equation solution that treats the ice as an elastic medium is presented. The solution is benchmarked against a derived elastic normal mode solution for range-independent underwater acoustic propagation. Results from both solutions accurately predict plate flexural modes that propagate in the ice layer, as well as Scholte interface waves that propagate at the boundary between the water and the seafloor. The parabolic equation solution is used to model a scenario with range-dependent ice thickness and a water sound speed profile similar to those observed during the 2009 Ice Exercise (ICEX) in the Beaufort Sea.
authors.affiliation: Department of Applied Mathematics and Statistics, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA.
authors.forename: Jon M
authors.initials: JM
authors.lastname: Collis
authors.affiliation: Department of Mathematics, Marist College, 3399 North Road, Poughkeepsie, New York 12601, USA.
authors.forename: Scott D
authors.initials: SD
authors.lastname: Frank
authors.affiliation: Applied Research Laboratories, The University of Texas at Austin, Austin, Texas 78713, USA.
authors.forename: Adam M
authors.initials: AM
authors.lastname: Metzler
authors.affiliation: Department of Applied Mathematics and Statistics, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA.
authors.forename: Kimberly S
authors.initials: KS
authors.lastname: Preston