Reflection of Acoustic Wave through Multilayered Porous Sea Ice Sandwiched between the Water and Air Half-Spaces

Abstract

To establish an accurate sea ice model is a tremendous challenge in Arctic acoustic research. Regarding this matter, a multilayered porous sea ice model is proposed based on Biot’s theory in this paper. Assuming that the model is sandwiched between the water and air half-spaces, the reflection coefficient of an incident wave from water into ice is deduced and contrasted with the solution calculated by impedance transfer method (ITM) to demonstrate the verification of the model. Furthermore, the influences of frequency, porosity and layering on reflection coefficients are analyzed. The results reveal that the reflection coefficient is closely associated with layering and porosity. Therefore, it is reasonable and necessary to simultaneously take the layering and porosity of ice into consideration. Different from the existing layered or porous ice model, the presented model synthesizes the layered characteristic and porous structure of ice, which better portrays the real condition of sea ice. It is an improvement of the broadly used stratified or porous sea ice model, which provides ideas for further sea ice modeling.

Keywords

• layering
• porosity
• Biot’s theory
• reflection