Abstract
Underwater sound in the oceans has been significantly rising in the past decades due to an increase in human activities, adversely affecting the marine environment. In order to assess and limit the impact of underwater noise, the European Commission’s Marine Strategy Framework Directive (MSFD) included the long-term monitoring of low-frequency underwater sound as a relevant indicator to achieve a good environmental status. There is a wide range of commercial hydrophones and observing platforms able to perform such measurements. However, heterogeneity and lack of standardization in both hydrophones and observing platforms makes the integration and data management tasks time-consuming and error-prone. Moreover, their power and communications constraints need to be addressed to make them suitable for long-term ocean sound monitoring. Measured underwater sound levels are challenging to compare because different measurement methodologies are used, leading to a risk of misunderstandings and data misinterpretation. Furthermore, the exact methodology applied is not always public or accessible, significantly reducing ocean sound data re-usability. Within this work, a universal architecture for ocean sound measurement is presented, addressing hydrophone integration, real-time in situ processing and data management challenges. Emphasis is placed on generic and re-usable components, so it can be seamlessly replicated and deployed in new scenarios regardless of the underlying hardware and software constraints (hydrophone model, observing platform, operating system, etc.). Within the proposed architecture, a generic implementation of an underwater sound algorithm based on underwater noise measurement best practices is provided. Standardized and coherent metadata with emphasis on strong semantics is discussed, providing the building blocks for FAIR (Findable, Accessible, Interoperable, Reusable) ocean sound data management.
Highlights
There has always been underwater background sound in the oceans due to natural factors
In order to achieve a good environmental status in European waters, the European Parliament approved the Marine Strategy Framework Directive (MSFD) which aims to protect the marine environment and ecosystem. This directive includes a set of indicators to measure the status of European waters, including maximum ocean underwater sound levels considered as acceptable (MSFD indicator 11.2.1)
The Sensor Web Enablement (SWE) Bridge provides the averaged mean of several Root Mean Squared pressure (RMS) values for two reasons: to maintain the same time window used in Sound Pressure Level (SPL) and Sound Exposure Level (SEL) calculations, and to prevent the use of very large buffer which may result in memory overflow and excessive computational cost
Summary
There has always been underwater background sound in the oceans due to natural factors. A universal architecture for in situ, real-time ocean sound monitoring is proposed, compliant with the needs of the ocean observing community (i.e. MSFD indicators) and following best practices on underwater sound measurement methodologies [22], [23]. This architecture addresses interoperability issues at both sensor integration and data management levels by proposing a solution based on the SWE framework. The paper closes with conclusions and an outlook to future work
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
