Turning Up Ocean Temperature & Volume – Underwater Soundscapes in a Changing Climate

Freeman Lauren – lauren.a.freeman3.civ@us.navy.mil

Instagram: @laur.freeman

NUWC Division Newport, NAVSEA, Newport, RI, 02841, United States

Dr. Lauren A. Freeman, Dr. Daniel Duane, Dr. Ian Rooney from NUWC Division Newport and
Dr. Simon E. Freeman from ARPA-E

Popular version of 1aAB1 – Passive Acoustic Monitoring of Biological Soundscapes in a Changing Climate
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018023

Climate change is impacting our oceans and marine ecosystems across the globe. Passive acoustic monitoring of marine ecosystems has been shown to provide a window into the heartbeat of an ecosystem, its relative health, and even information such as how many whales or fish are present in a given day or month. By studying marine soundscapes, we collate all of the ambient noise at an underwater location and attribute parts of the soundscape to wind and waves, to boats, and to different types of biology. Long term biological soundscape studies allow us to track changes in ecosystems with a single, small, instrument called a hydrophone. I’ve been studying coral reef soundscapes for nearly a decade now, and am starting to have time series long enough to begin to see how climate change affects soundscapes. Some of the most immediate and pronounced impacts of climate change on shallow ocean soundscapes are evident in varying levels of ambient biological sound. We found a ubiquitous trend at research sites in both the tropical Pacific (Hawaii) and sub-tropical Atlantic (Bermuda) that warmer water tends to be associated with higher ambient noise levels. Different frequency bands provide information about different ecological processes (such as fish calls, invertebrate activity, and algal photosynthesis). The response of each of these processes to temperature changes is not uniform, however each type of ambient noise increases in warmer water. At some point, ocean warming and acidification will fundamentally change the ecological structure of a shallow water environment. This would also be reflected in a fundamentally different soundscape, as described by peak frequencies and sound intensity. While I have not monitored the phase shift of an ecosystem at a single site, I have documented and shown that healthy coral reefs with high levels of parrotfish and reef fish have fundamentally different soundscapes, as reflected in their acoustic signature at different frequency bands, than coral reefs that are degraded and overgrown with fleshy macroalgae. This suggests that long term soundscape monitoring could also track these ecological phase shifts under climate stress and other impacts to marine ecosystems such as overfishing.

A healthy coral reef research site in Hawaii with vibrant corals, many reef fish, and copious nooks and crannies for marine invertebrates to make their homes.
Soundscape segmented into three frequency bands capturing fish vocalizations (blue), parrotfish scrapes (red), and invertebrate clicks along with algal photosynthesis bubbles (yellow). All features show an increase in ambient noise level (PSD, y-axis) with increasing ocean temperature at each site studied in Hawaii.

Putting Ocean Acoustics on the stage to address climate change

Kyle M. Becker – kyle.becker1@navy.mil

co-chair, Interagency Working Group on Ocean Sound and Marine Life (IWG-OSML)
Washington, DC 20001
United States

Thomas C Weber – member, IWG-OSML, Washington, DC
Heather Spence – co-chair, IWG-OSML, Washington, DC
Grace C Smarsh – Executive Secretary, IWG-OSML, Washington, DC

Popular version of 1aAB9 – Ocean Acoustics and the UN Decade of Ocean Science for Sustainable Development
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018031

The Acoustic Environment is, collectively, the combination of all sounds within a given area modified by interactions with the environment. This definition includes both the sounds of nature and human use and is used by the US National Park Service as a basis for characterizing, managing, and preserving sound as one of the natural resources within the park system. Thinking in terms of a theatre, the Acoustic Environment is where scenes emerge from the interaction of individual actors (or sources) with all other aspects of the stage (the environment). The audience (or receiver) derives information from a continuous series of actions and interactions that combine to tell a story. In developing the Ocean Decade Research Programme on the Maritime Acoustic Environment (OD-MAE https://tinyurl.com/463uwjk5) we applied the theatre analogy to underwater environments, where acoustic scenes result from the dynamic combination of physical, biological, and chemical processes in the ocean that define the field of oceanography. In the science of Ocean Acoustics, these highly intertwined relationships are reflected in the information available to us through sound and can be used as a means to both differentiate among various ocean regions and tell us something – stories – about processes occurring within the oceans. The use of sound for understanding the natural environment is particularly effective in the oceans because underwater sound travels very efficiently over large distances, allowing us to probe the vast expanses of the globe. As an example of this, the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) is capable of monitoring nearly the entire volume of the world’s oceans for underwater nuclear explosions with only eleven underwater acoustic listening stations.

In the context of the UN Decade of Ocean Science for Sustainable Development (oceandecade.org), the OD-MAE program seeks to raise awareness about and support research related to the information available through sound that reflects the regional ocean environment and its state. For example, the noisiest places in the ocean have been found to be in Alaskan and Antarctic fjords where sound energy levels created by the release of trapped air by melting ice exceed that of many other sources, including weather and shipping[1]. Sound energy increases with melt rate as more bubbles are released, providing information about the amount of fresh water being added into the oceans along with other climate indicators.

Representative glacial environment. Image credit: National Park Service

Ambient Sound recorded near Hubbard and Turner Glaciers near Yakutat, AK. Credit: Matthew Zeh, Belmont University and Preston Wilson, Univ. of Texas at Austin

Similarly, in warmer climates, the acoustic environment of coral reefs can provide scientists an indication of a reef system’s health. Healthy reef systems support much more life and as a result more sound is produced by the resident marine life. This is evident when contrasting the sounds recorded at a healthy reef system to those recorded at a location that experienced bleaching owing to increased water temperature and climate change[2].

Representative healthy and degraded reef systems. Image credits NOAA

Sound of representative healthy reef system. Credit: Steve Simpson, University of Bristol, UK

Sound of representative degraded reef system. Credit: Steve Simpson, University of Bristol, UK

As a research program, the OD-MAE seeks to quantify information about the acoustic environment such that we can assess the current state and health of the oceans, from shallow tropical reefs to the very deepest depths of the ocean. Telling the stories of the ocean by listening to it will help provide knowledge and tools for sustainably managing development and even restoring maritime environments[3].


[1] Pettit, E. C., Lee, K. M., Brann, J. P., Nystuen, J. A., Wilson, P. S., and O’Neel, S. (2015), Unusually loud ambient noise in tidewater glacier fjords: A signal of ice melt. Geophys. Res. Lett., 42, 2309– 2316. doi: 10.1002/2014GL062950.
[2] https://artsandculture.google.com/story/can-we-use-sound-to-restore-coral-reefs/ RgUBYCe8v8Ol0Q [last visited 5.3.2023]
[3] Williams, B. R., McAfee, D., and Connell, S. D.. 2021. Repairing recruitment processes with sound technology to accelerate habitat restoration. Ecological Applications 31( 6):e02386. 10.1002/eap.2386

Featured Image Credit: National Park Service

A virtual reality system to ‘test drive’ hearing aids in real-world settings

Matthew Neal – mathew.neal.2@louisville.edu
Instagram: @matthewneal32

Department of Otolaryngology and other Communicative Disorders
University of Louisville
Louisville, Kentucky 40208
United States

Popular version of 3pID2 – A hearing aid “test drive”: Using virtual acoustics to accurately demonstrate hearing aid performance in realistic environments
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018736

Many of the struggles experienced by patients and audiologists during the hearing aid fitting process stem from a simple difficulty: it is really hard to describe in words how something will sound, especially if you have never heard it before. Currently, audiologists use brochures and their own words to counsel a patient during the hearing aid purchase process, but a device often must be purchased first before patients can try them in their everyday life. This research project has developed virtual reality (VR) hearing aid demonstration software which allows patients to listen to what hearing aids will sound like in real-world settings, such as noisy restaurants, churches, and the places where they need devices the most. Using the system, patient can make more informed purchasing decisions and audiologists can program hearing aids to an individual’s needs and preferences more quickly.

This technology can also be thought of as a VR ‘test drive’ of wearing hearing aids, letting audiologists act as tour guides as patients try out features on a hearing aid. After turning a new hearing aid feature on, a patient will hear the devices update in a split second, and the audiologist can ask, “Was it better before or after the adjustment?” On top of getting device settings correct, hearing aid purchasers must also decide which ‘technology level’ they would like to purchase. Patients are given an option between three to four technology levels, ranging from basic to premium, with an added cost of around $1,000 per increase in level. Higher technology levels incorporate the latest processing algorithms, but patients must decide if they are worth the price, often without the ability to hear the difference. The VR hearing aid demonstration lets patients try out these different levels of technology, hear the benefits of premium devices, and decide if the increase in speech intelligibility or listening comfort is worth the added cost.

A patient using the demo first puts on a custom pair of wired hearing aids. These hearing aids are the same devices sold that are sold in audiology clinics, but their microphones have been removed and replaced with wires for inputs. The wires are connected back to the VR program running on a computer which simulates the audio in a given scene. For example, in the VR restaurant scene shown in Video 1, the software maps audio in a complex, noisy restaurant to the hearing aid microphones while worn by a patient. The wires send the audio that would have been picked up in the simulated restaurant to the custom hearing aids, and they process and amplify the sound just as they would in that setting. All of the audio is updated in real-time so that a listener can rotate their head, just as they might do in the real world. Currently, the system is being further developed, and it is planned to be implemented in audiology clinics as an advanced hearing aid fitting and patient counseling tool.

Video 1: The VR software being used to demonstrate the Speech in Loud Noise program on a Phonak Audeo Paradise hearing aid. The audio in this video is the directly recorded output of the hearing aid, overlaid with a video of the VR system in operation. When the hearing aid is switched to the Speech in Loud noise program on the phone app, it becomes much easier and more comfortable to listen to the frontal talker, highlighting the benefits of this feature in a premium hearing aid.

Using ultrasound as an antibody in Alzheimer’s and as a drug dose enhancer in cancer patients

Elisa Konofagou – ek2191@columbia.edu

Columbia University, 1210 Amsterdam Ave, New York, New York, 10027-7003, United States

Popular version of 2aBAa1 – Neuronavigated focused ultrasound for clinical bbb opening in alzheimer’s and brain cancer patients
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018295

Ultrasound is widely known as an imaging modality in obstetrics and cardiology as well as several other applications but less known regarding its therapeutic effects despite its recent approvals in the clinic for ablation of prostate cancer and essential tremors. In the studies presented, we demonstrate that focused ultrasound (FUS) can be used in conjunction with microbubbles to open the blood-brain barrier (BBB) through the intact scalp of Alzheimer’s and pediatric tumor patients. The BBB is the main defense of the brain against toxic molecules but also prevents drugs from treating brain disease. In the case of Alzheimer’s, we demonstrate for the first time that the BBB opening resulting from FUS in the prefrontal cortex acts as an antibody in the brain. BBB opening results into a beneficial immune response in the brain that significantly reduces the beta amyloid in the region where ultrasound opened the blood-brain barrier. This was shown in 5 patients with Alzheimer’s.

In the case of the pediatric tumor patients, we aimed into the stem, which is a critical region between the spinal cord and the brain. The tumors in the pediatric patients are gliomas that grow in the stem where critical nerve fibers run through and they are therefore inoperable. We showed for the first time that BBB opening can be repeatedly induced with FUS in conjunction with microbubbles safely and efficiently in patients with pediatric glioma tumors in the stem. In this case, we used FUS in conjunction with a drug that, when crossing the blood-brain barrier, increases its efficiency. The patients reported smoother limb movement after treatment with the drug potentially acting more potently on the tumor.

It was concluded that ultrasound can safely open the blood-brain barrier in both patients as young as 6 years old to as old as 83 years old completely noninvasively and more importantly reduce the disease pathology and/or symptoms. The system is thus versatile, does not require a dedicated MR system or to be performed in the MR scanner unlike other systems and the entire procedure can last less than 30 min from start to finish. Ultrasound can thus be used alone or in conjunction with a drug in order to change the current dire landscape of treatment of brain disease. Finally, we show how Alzheimer’s beta amyloid and tau are excreted from the brain and can be detected with a simple blood test.

Whispers from the Deep Sea: The Subtle Sounds of Hydrothermal Vents #ASA183

Whispers from the Deep Sea: The Subtle Sounds of Hydrothermal Vents #ASA183

Passive acoustic monitoring can characterize the sounds of hydrothermal vents, informing the environmental impacts of deep-sea mining and possibly locating similar sites throughout the solar system.

Media Contact:
Ashley Piccone
AIP Media

NASHVILLE, Tenn., Dec. 8, 2022 – Deep-sea hydrothermal vents host unique life that survives without sunlight, and they play a significant role in the cycle of heat, water, and chemicals within the ocean. But long-term monitoring of these vents is difficult because of their hot and caustic characteristics.

Ocean Networks Canada’s hydrophone and the Deep Acoustic Lander are used to monitor hydrothermal vents. Credit: Ocean Networks Canada

In his presentation, “The soundscape of two deep-sea hydrothermal vent sites,” Brendan Smith will describe how hydrophones can listen to the sounds of these vents, informing the environmental impacts of deep-sea mining and assisting with interplanetary exploration. The 183rd Meeting of the Acoustical Society of America will run Dec. 5-9 at the Grand Hyatt Nashville Hotel, and Smith’s session will take place on Dec. 8 at 9:30 a.m. Eastern U.S. in the North Coast A room.

Smith and his PhD supervisor Dr. David Barclay used hydrophones operated by Ocean Networks Canada in the Pacific Ocean and the European Multidisciplinary Seafloor and water column Observatory in the Atlantic Ocean to monitor two vents on the seafloor. Barclay also developed a custom autonomous device that helps determine the source of a sound, which Smith will deploy during a research cruise in 2023. Both are noninvasive ways to study the vents, and both are sustainable in the long term because they work from a safe distance.

Hydrothermal vents produce subtle sounds near the low end of the human hearing range. These noises fluctuate with the flow and temperature of the vent, and biological sources nearby can also contribute to the soundscape.

“Ultimately, our objective is to find the relationship between vent parameters such as flow rate or temperature and the sound they produce,” Smith said. “It is also important to understand all of the contributions to the soundscape at hydrothermal vents, not just the sounds produced by the vents themselves. Surface weather, marine life, and anthropogenic sources such as shipping all contribute to the soundscape.”

Proposed industrial use of hydrothermal vents through deep-sea mining would alter their soundscape and impact the surrounding organisms. Understanding the acoustics in the vicinity could help predict and prevent environmental impacts.

“Characterizing the sound produced by hydrothermal vents can also help us locate new, unexplored vent sites from a long distance,” said Smith. “This could be used to help find new vent sites on Earth, but also elsewhere in the solar system, such as Saturn’s moon Titan or Jupiter’s moon Europa.”

Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eppro02.ativ.me/web/planner.php?id=ASAFALL22&proof=true

In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are 300 to 500 word summaries of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org.  For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Snap, Crackle, Pop: Healthy Coral Reefs Brimming with Noise

Snap, Crackle, Pop: Healthy Coral Reefs Brimming with Noise

Monitoring their soundscape can provide a long term, nonintrusive, inexpensive method for tracking the state of reefs around the world

Media Contact:
Larry Frum
AIP Media

DENVER, May 25, 2022 – A healthy coral reef is loud. Like a busy city, the infrastructure leads to more organisms and activity, and more background noise. Every time an invertebrate drags their hard shell over the coral, or a fish takes a bite of its food, they add to the soundscape.

Vocal fish, whales, and dolphins occasionally interrupt with louder grunts and calls. Altogether, the hundreds of thousands of animals living in the reef sound like static on the radio, or the snap, crackle, and pop of a bowl of Rice Krispies as you pour milk on the cereal, when the coral reef is healthy. The sound changes for reefs that are not healthy, becoming quieter and less diverse.

Lauren Freeman, of the U.S. Naval Undersea Warfare Center Newport, will present experiment results of passively acoustically monitoring coral reefs to get a snapshot of their health at the 182nd Meeting of the Acoustical Society of America at the Sheraton Denver Downtown Hotel. The presentation, “Coral Reef & Temperate Coastal Soundscape Features Evident in Directional and Omnidirectional Passive Acoustic Time Series,” will take place May 25 at 11:35 a.m. Eastern U.S.

Passive acoustic monitoring of coral soundscapes offers a long-term, nonintrusive, and inexpensive way to track the state of reefs around the world, which are threatened by humanity via fishing, pollution, and climate change.
Compared to healthy reefs, degraded coral communities don’t have as rich or diverse of a soundscape. There tend to be fewer fish calls and more high frequency noise from algae photosynthesizing and releasing bubbles of oxygen, which ring out as they rise through the water.

“There is a natural competition between corals and macroalgae on all coral reefs. In most cases with a dying or degraded reef, the macroalgae is winning and covers a lot more of the surface,” said Freeman. “On a pristine reef, you would see very little macroalgae, and a lot of herbivorous fish that help eat the macroalgae.”

Freeman and her team deployed an acoustic array to monitor reefs off the coast of Hawaii. They compared these results to similar data from Bermuda and New England. Interestingly, Hawaii and Bermuda both showed a characteristic reef evening chorus, where the sound levels increased immediately prior to sunset. The New England reef underwent similar changes near dusk.

“Almost every time I conduct an experiment, we learn more about the complexities and intricacies of ambient biological soundscapes,” said Freeman. “It’s so exciting to continue to discover more about ocean ecosystems.”

Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eventpilotadmin.com/web/planner.php?id=ASASPRING22
Press Room: https://acoustics.org/world-wide-press-room/

In the coming weeks, ASA’s Worldwide Press Room will be updated with additional tips on dozens of newsworthy stories and with lay language papers, which are 300 to 500 word summaries of presentations written by scientists for a general audience and accompanied by photos, audio and video. You can visit the site during the meeting at https://acoustics.org/world-wide-press-room/.

We will grant free registration to credentialed journalists and professional freelance journalists. If you are a reporter and would like to attend, contact AIP Media Services at media@aip.org. For urgent requests, staff at media@aip.org can also help with setting up interviews and obtaining images, sound clips, or background information.

The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.