Opportunistic ship source level measurements in the Western Canadian Arctica)

Area of Science:

• Marine acoustics
• Environmental science
• Arctic research

Background:

• Climate change is increasing ship traffic in the Arctic.
• Rising underwater noise levels pose a threat to the Arctic ecosystem.
• Accurate measurements are needed to understand shipping's acoustic impact.

Purpose of the Study:

• To present a method for calculating opportunistic source levels (SLs) of individual ships.
• To quantify the impact of shipping on underwater noise in the Western Canadian Arctic.
• To compare measured SLs with a predictive model (JOMOPANS-ECHO SL).

Main Methods:

• Utilized passive acoustic data from six Arctic locations (2018-2022).
• Integrated Automatic Identification System (AIS) data with acoustic data and a hybrid sound propagation model.
• Calculated ship SLs within a 5 km radius of measurement sites.

Main Results:

• 66 measurements from 11 unique vessels were obtained.
• For vessels with propeller cavitation, SLs positively correlated with speed and length.
• The JOMOPANS-ECHO SL model showed good agreement for container ships, tankers, and passenger vessels, but not for some polar-class ships.

Conclusions:

• The developed method provides valuable data on ship underwater radiated noise in the Arctic.
• Discrepancies with the JOMOPANS-ECHO SL model for polar-class ships highlight the need for further, controlled measurements.
• Understanding ship noise is critical for mitigating ecological impacts in a changing Arctic environment.