Comparison of underwater noise at the Chukchi Plateau under open-water and ice-covered conditions

• Published in: Polar Science
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Arctic underwater noise; Ice concentration; Ice-generated noise; Wind-generated noise; Chukchi plateau; Arctic; Arctic Ocean; Chukchi; Global warming; Polar Science; Sea ice
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=16975; http://id.nii.ac.jp/1291/00016844/

A comparison study on underwater noise at the Chukchi plateau with and without ice cover helps to understand the rapidly changing Arctic Ocean, especially in the context of global warming. Underwater noise recorded at a receiving depth of 519.5 m, from September 9, 2017 to March 8, 2018, on the Chukchi Plateau had been investigated. When the sea surface was ice-free, underwater noise on the Chukchi Plateau was dominated by wind-generated noise for high wind speed and there was no significant shipping in this sea area. When the sea surface was ice-covered, underwater noise was dominated by ice-generated noise. Under open-water conditions, the noise spectrum means and percentiles were greater than those under ice-covered conditions. The differences of mean and median levels between open-water and ice-covered conditions were all almost less than 3 dB in the range 20–100 Hz; whereas, they were greater than 3 dB in the 100 Hz–2 kHz band and increased with increasing frequency. Although the transient signals generated by sea ice activities would cause the noise spectrum level to increase suddenly under ice-covered conditions, the underwater noise was still shown relatively quiet compared with that under open-water conditions.