Recent advances in polar acoustics research in the continually changing Arctic

Under the general trend of global warming, the climate and marine environment of the Arctic seas are changing persistently, which are manifestations of gradual decrease in the volume of sea ice, the gradual expansion of the open sea area in summer, the continuous reduction of multi-year ice. The hydrological stratification in the ice edge zone has become more complex. Under the influence of the phenomenon in oceanographical variabilities, the underwater acoustic environment in Arctic is also undergoing persistently changes. Starting from the characteristics of waveguide environments such as sea ice, hydrology, and seafloor in the new epoch Arctic seas, this article summarizes the latest research progress of the acoustic propagation characteristics, under-ice noise characteristics, and under-ice reverberation characteristics of the Arctic. Combining the domestic and foreign research progress of the Arctic acoustic observation experiments, special emphases are given on the comprehensive environmental observation of underwater acoustics, under-ice acoustic communication and navigation, and ice morphology acoustic monitoring. Finally, the research of the Arctic underwater acoustics is summarized and the future development trends are predicted.