Global Hydrophone Network | International Quiet Ocean Experiment (IQOE)

Global Hydrophone Network

Hydrophones have been deployed in a variety of locations around the world, particularly in the past 20 years. These deployments have been made by academic scientists, national governments (military and non-military), non-governmental organizations, and industry. In some isolated cases, there has been small-scale coordination internationally among hydrophone operators, but IQOE seeks to promote more extensive cooperation. Such cooperation is especially important for implementation of the Ocean Sound Essential Ocean Variable of the Global Ocean Observing System.

The IQOE Science Committee approved formation of an IQOE Working Group on Global Hydrophone Network to implement the actions described below.

Chair
Peter Tyack (USA)

Other Members
Heidi Ahonen (Norway)
Tom Akamatsu (Japan)
Carrie Wall Bell (USA)
Wayne Crawford (France)
Simon Elwen (South Africa)
Hilary Moors-Murphy (Canada)
Miles Parsons (Australia)
Denise Risch (UK)
Karolin Thomisch (Germany)

Terms of Reference

The IQOE Working Group on Global Hydrophone Network will conduct the following activities in 2022-2025:

Review the existing set of digital recordings of ocean sound (pressure and particle motion) to identify gaps in coverage and recording locations. Attempt to fill gaps by contacting ocean sound observers who have not yet provided metadata.
Review metadata collected from ocean sound observers to determine if any changes need to be made in what metadata are collected. Find any relevant metadata standards and make the metadata adhere to standards.
Create policy for data sharing among operators and public.
Develop an independent international organization of ocean sound observers by the end of 2025.
Examine Table 4.1 from Ocean Sound Essential Ocean Variable Implementation Plan to determine how a hydrophone network could contribute.
Determine how the ocean bottom seismometer network could be linked to hydrophone network.
Propose how this WG could evolve to a participant in the GOOS system.
Identify legal/national security implications to a global hydrophone system.

Status

IQOE is in its 9th year as a 10-year project and continues to implement of its Science Plan (available here). IQOE has successfully coordinated a variety of activities in ocean acoustics and bioacoustics through IQOE working groups on the use of acoustics to assess biodiversity, the importance of acoustic observations in the Arctic Ocean, standards for reporting ocean acoustic and bioacoustic data for IQOE, software for making acoustic observations comparable worldwide, and recommendations for implementation of an Ocean Sound Essential Ocean Variable for the Global Ocean Observing System. IQOE progress has been documented since June 2018 through IQOE Newsletters and since the beginning of the project through other products. IQOE identified 2020 as the Year of the Quiet Ocean because of evidence that ocean sound decreased because of decreases in human activities in the ocean due to the COVID-19 pandemic.

Next Steps

Activities in 2024 will include actions to help implement the Ocean Sound Essential Ocean Variable Implementation Plan; continuation of new activities on low-cost ocean acoustic observing systems and expansion of the Open Portal to Underwater Sound (OPUS), implementation of the Global Library of Underwater Biological Sounds, sponsorship of the second World Ocean Passive Acoustic Monitoring Day; and meetings of IQOE working groups and Science Committee.