Review and discussion of recent publications on underwater noise from shipping

Abstract

The IMO is currently deliberating on revisions to the Guidelines for the reduction of underwater noise from commercial shipping. To shed light on the knowledge base that these deliberations are based on, and the views of important stakeholders, state-of-the-art papers on the issue of underwater shipping noise and mitigation of impacts on marine life through design, engineering and operational measures were reviewed in this project. These are the same publications that have been selected by the IMO to guide their deliberations in the latest round. This paper summarizes the current progress at the IMO, including the revised guidelines and proposed revisions by Japan, and puts it into context with the reviewed publications. Thirty-six papers on mitigation methods, modeling, measurement techniques and ecosystem impacts were reviewed. It is concluded that the most appropriate guidelines for many stakeholders would consist of: 1) clear procedures and instructions for setting and adhering to target noise level, 2) identifying measurement procedures, 3) numerical modeling, and 4) monitoring plan to achieve the goal. Based on the results of the paper review, we discuss future research approaches to establish useful guidelines.