Marine Acoustics News: Recent Advances and Global Initiatives
Marine acoustics is a rapidly evolving field with significant implications for ocean conservation, security, and scientific research. Recent years have seen advancements in technology, increased global collaboration, and a growing awareness of the importance of understanding underwater soundscapes. This article highlights some of the key developments and initiatives in marine acoustics.
Advancements in Underwater Sound Monitoring
Passive acoustic monitoring (PAM) has developed significantly over the last 20 years. Now hydrophones are being deployed in more locations, more often, by more people, than ever before. Several initiatives are underway to improve the accessibility and inclusivity of underwater sound monitoring.
This IQOE initiative is designed to make underwater sound monitoring more accessible and inclusive, by developing affordable, open-source hydrophones for research, education, and community science worldwide.
Through the Global Library of Underwater Biological Sounds (GLUBS), a call has gone out to hydrophone operators for their interest to participate in a World Oceans Passive Acoustic Monitoring (WOPAM) Day. The premise for the first year of this initiative is simple; to share data from any already planned deployments recording on June 8th for a collaborative study of our global aquatic soundscapes, whether in salt, brackish or freshwater.
IQOE's Role in Ocean Sound Data Collection
IQOE has been compiling metadata of ocean PAM recordings since early 2020. IQOE is in the process of collecting metadata for 2023 ocean sound observations. This map shows the locations for metadata collected so far.
Map of ocean sound observation locations for metadata collected by IQOE.
IQOE will close submission for the first metadata product on 30 April 2025. After this time, a DOI will be sought for the metadata product comprised of the short- and long-term public metadata, with all metadata providers listed as contributors to the product.
Peter Tyack, one of IQOE's co-chairs made a presentation about IQOE progress at the annual meeting of the Partnership for Observation of the Global Ocean (POGO), in Penang, Malaysia, from 25 to 28 February 2025.
Understanding Ocean Noise
Many factors influence the propagation of sound in the ocean, notes Michalopoulou. Among them are water temperature, the number of times sound waves bounce between the surface of the ocean and the seabed below, the slope of the ocean floor and its subsurface geologic profile. She integrates this acoustic data with mathematical models to understand how sound interacts with the seabed. She integrates this acoustic data with mathematical models to understand how sound interacts with the seabed. This helps predict how signals travel through water and what they should ‘look’ like when received.
“By ‘listening’ to the ocean, we can analyze its properties and characteristics without the need to physically deploy extensive equipment into the depths of the vast underwater world,” Michalopoulou said. She notes that in general, the warmer the water, the faster sound will travel between a source and a detector. Accordingly, investigating oceanic sound propagation relative to historic seasonal variations also promises to yield insights into climate change. Sound propagation can be affected by the ocean’s chemical composition as well.
Applications in Fisheries Management
Woods Hole Oceanographic Institution News & Insight: Listening to fish with passive acoustics: WHOI and NOAA Fisheries researchers adapt marine mammal detection technologies for fisheries management.
NOAA Fisheries Feature Story: Scientists Collecting Data on Commercial Fish Species in Wind Energy Lease Areas.
Defense and Security Applications
DSIT Solutions, a Rafael subsidiary that specializes in defensive systems against underwater threats, is moving forward with an IPO on the Tel Aviv Stock Exchange (TASE), The Jerusalem Post has confirmed. For over 30 years, the company has focused on underwater acoustics, producing systems that detect and track divers, submarines, and other underwater threats. Its products are used to secure ports, offshore energy infrastructure, naval bases, and critical undersea assets.
The company’s portfolio includes diver-detection sonar, anti-submarine warfare systems, underwater communication platforms, and acoustic training and simulation tools. DSIT reports that it invests over 10% of its revenue in research and development (R&D), allowing it to maintain a competitive position in a field that requires constant technological advancement. DSIT’s systems are deployed by navies, homeland security agencies, and commercial operators worldwide.
According to a report by Globes, DSIT will move forward with an IPO on the Tel Aviv Stock Exchange (TASE) at a company valuation of NIS 200 million to NIS 250 million. The report said that DSIT hopes to raise about NIS 50 million, which would be channeled into the company’s coffers for investment.
A Greyshark underwater drone or AUV (autonomous underwater vehicle).
With three-quarters of the Earth’s surface covered by ocean, the sea has long been central to global trade, security, and power projection. Recent conflicts in Ukraine and in the Red Sea have accelerated the adoption of unmanned maritime systems because for many countries, the sea is the primary trade route. Any disruption can significantly increase costs and impact both national and global energy security.
The sea also holds critical underwater infrastructure with networks of cables spanning an estimated millions of miles across the Mid-Atlantic seabed from North America to Europe and Asia. Disruptions to such systems can have devastating consequences to communications, financial transactions, electricity, and more.
There is a growing recognition within the defense sector that underwater autonomy is critical to maintaining strategic advantage, particularly in regions where access and visibility are limited.
Industry Events and Collaborations
From 02-04 November Steve Psaras, MAI’s VP for Virginia Operations, and Garth Anderson, MAI Senior Analyst, took part in INDOPACIFIC 2025 in Sydney, Australia. The Indo Pacific International Maritime Exposition is the region’s premier commercial maritime and naval defense exposition, connecting Australian and international defense, industry, government, academia, and technology leaders, in the national interest. This year’s focus was heavily centered on AUKUS supporting technologies, leveraging new AUKUS incentives for US and Australian industry collaboration.
Marine Acoustics Inc and our partner, Spear AI Inc, are pleased to announce that we were awarded Phase 1 NAVSEA SBIR N251-47 Multi-sensor and Acoustic Contact Localization through Artificial Intelligence/Machine Learning.
Marine Acoustics Inc’s Jacquie Workman attended the most recent Office of Naval Research (ONR) Task Force Ocean (TFO) Tactical Oceanography Technical Exchange Meeting (TOTEM) at Massachusetts Institute of Technology Lincoln Laboratories, additionally she served as a co-chair for the Intelligence Update.
Marine Acoustics, Inc is excited to share that Garth Anderson and Shae Zaben have joined the MAI team. Garth is a retired Submarine Sonar Technician and Acoustic Intelligence (ACINT) Specialist Master Chief and since retiring from Naval service he has continued working in the undersea domain at several vital positions as a government contractor. Shae is a recently retired Surface Sonar Technician and ACINT Specialist Master Chief after 29 years of service.