Effects of rough sea-ice on the sound propagation in the Arctic ocean

摘要

Aiming at the complex and variable environment of Arctic ice, a stochastic physical model of sea ice is proposed to better represent the roughness of sea ice and study the acoustic characteristics of typical Arctic ice. The sea-ice is regarded as the uniform elastomer with rough interface, and the randomly distributed protuberance on the lower layer of the sea-ice are ice ridges. Referring to the BT scattering model, the sea-ice thickness data measured by the up-looking sonar, which released from the National Snow and Ice Data Center. and the randomly distributed ice ridge is regarded as a randomly distributed isosceles triangle to establish a random sea ice physical model, combined with plane elasticity. The ice layer reflection model is used to obtain the ice layer reflection coefficient; The last year's data is used as the test group, and the rest as the training group, the ray theory model is used to calculate the propagation loss under the ice covered and compare them. The results show that there is scattering phenomenon when sound waves propagate under the rough ice interface. It is difficult to observe the sound shadow region under rough ice. Comparing the sound field under sea-ice between the training group and the test group, it is found that the sound transmission loss of the two groups is consistent on the whole. It indicates that the rough sea ice model proposed can better characterize the roughness of the interface under the real ice layer.