Researchers aim to produce the first global underwater soundscape

Researchers from the University of Portsmouth are aiming to generate the first global underwater soundscape from some of the noisiest and quietest areas of the ocean.

The project will collect biologically-produced sounds from marine life.

This research will help identify how human activities and noise pollution have impacted on the global marine environment and discover whether remote areas of the world’s oceans still remain pristine.

The data will be collected by world record sailor Alex Alley, as he aims to break the solo non-stop around the world record in his 40 foot yacht – Pixel Flyer. Alex is aiming to leave Gosport Harbour on Tuesday 30 October and will be aiming to beat the record which currently stands at 137 days, 20 hours 1 minute and 57 seconds.

On his attempt, Alex will be travelling through some of the most remote parts of the world’s oceans, thousands of miles from land. The ‘quiet’ areas will provide researchers with unique data of what human and wildlife noises are able to be detected. While underwater soundscapes have been generated before, this is the first time that one will be created that encompasses the whole globe in a single circumnavigation.

Alex Alley said: “It’s incredible to have the opportunity to sail solo non-stop around the world and try and break the record. It’s also a great opportunity to do some research at the same time. Over five times as many people have been in to space than sailed solo non-stop around the world and we still know so little about the remote oceans.

“Working with the research team at the University of Portsmouth we thought a sound scape would be a unique and interesting project. For me, the priority is to break the record so I need something that won’t have much impact on the boats performance. So after much head scratching we came up with a design for a foil which houses a hydrophone and a thermometer.

“I’m really pleased to be a part of this very exciting project and look forward to seeing what we find.”

Biotic sound sources: A and B show the clicks and whistles of bottlenose dolphins, C shows mulloway fish choruses, and D shows snapping shrimp

Once the data has been collected, the Portsmouth researchers will analyse it using spectrograms to identify different sound sources, particularly those produced by marine life and human-related activities. They will then assess the ‘noisiness’ of different sections of Alex’s journey, to see which areas remain acoustically pristine versus those that show evidence of human modification.

Dr Sarah Marley, a Lecturer in Marine Vertebrate Zoology from the University’s Institute of Marine Sciences, will be leading the project to analyse the soundscape. She said: “The ocean has always been a noisy place. The marine environment is full of naturally-occurring sounds from waves and weather, as well as biologically-produced sounds from invertebrates, fish and marine mammals. Together, these sounds create an ‘underwater soundscape’. Studying the soundscape of marine habitats can tell us a lot about the ocean, in terms of both the environmental conditions and the presence of aquatic life.

“However, as human activities continue to expand across the ocean, underwater soundscapes are changing. Acoustic habitats are becoming increasingly dominated by anthropogenic noise, which can have a range of impacts on aquatic animals – from behavioural disturbance to communication masking to physiological damage. Therefore, it is important to study both ‘quiet’ and ‘noisy’ areas in order to understand the effects of man-made noise on our oceans.”

The ocean sounds will be collected an RS-Orca sound recorder that will be installed on the Pixel Flyer, supplied by Hampshire-based marine technology firm RS Aqua.

Dr Ryan Mowat, an application scientist with RS-Aqua, said: “The RS-Orca is one of the world’s leading and most versatile underwater acoustic recorders. Its wide listening bandwidth allows it to record everything from the low frequency noise of oil and gas activity, to the very high frequency vocalisations and echo location techniques used by marine mammal species. It will be very exciting to see the range of underwater noise that is recorded on the Pixel Flyer’s world circumnavigation, and any noisy hotspots it picks up.”

Professor Alex Ford from the University’s Institute of Marine Sciences said: “We are delighted to be working with Alex Alley on his solo world record attempt to circumnavigate the globe. We’ve been extremely fortunate in Portsmouth to have so many world-class sailors in the area prepared to take on the role environmental ambassadors of the ocean.

“Having such a large dataset does not come without some logistical problems in terms of storing and analysing data during the four-month voyage. We aim to make the most of the latest in artificial intelligence and machine learning technologies to decipher the information we are recording.

“This is a transdisciplinary project which will require the skill sets of not only Portsmouth’s marine biologists but also computational musicians and scientists from our School of Computing.”

You can follow Alex’s progress here – https://my.yb.tl/alexalley

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