Ocean acoustics is the study of sound in the marine environment – a mixture of physical noise, biological noise, geological noise, and anthropogenic (human-caused) noise. By studying sound in the ocean, scientists advance our understanding of the ocean, its inhabitants, natural processes, and how humans have influenced the ocean system. Scientists can use active or passive acoustic technology. Active acoustics involves emitting sound waves and analyzing their echoes to study objects in the ocean, such as seafloor topography, fish populations, or a shipwreck. In contrast, passive acoustics involves capturing sounds from the surrounding environment with an acoustic device to monitor and estimate marine life behaviors and abundance, or investigate undersea volcanoes and earthquakes. 

As sound is a primary means of communication for many marine species, disruption in acoustic environments can impact their behavior and survival. Specifically, ocean noise causes stress on marine life, disrupting communication, navigation, and marine behaviors of whales, dolphins, and fish. Prolonged exposure to high levels of underwater noise can lead to hearing loss, reduced feeding efficiency, and increased vulnerability to predators, threatening the existence of many organisms. Reducing ocean noise pollution contributes to healthier marine environments, supporting biodiversity and environmental sustainability.

Lastly, the study of ocean acoustics is also critical to society and our national security. The U.S. Navy is specifically interested in enhancing underwater navigation and communication, and the detection of submarines or other vessels. This knowledge helps improve maritime safety and maintains our nation’s strategic defense in global waters. But studying sound is also essential for protecting marine ecosystems, which directly impact our food security, livelihoods, and the health of coastal communities which are key to the growing blue economy.