The Comprehensive Nuclear Test Ban Treaty Organization operates a global International Monitoring System, with 11 hydroacoustic stations around the globe located in the deep-sea sound channel. Continuous measurements provide up to 20 years of sound pressures at frequencies of up to 100 Hz, depending on when each station was installed. These relatively long timescales allow investigating the effects of climate over that period. This presentation will show data from CTBT stations H11 (Wake Island, in the North Pacific) and H01 (Cape Leeuwin, in the Indian Ocean). Multiscale aggregations of 1-minute power spectral density (PSD) levels and sound energy measures over several days are used to show their correlation with sea surface temperature (SST) measurements at different timescales. In particular, we can detect seasonal changes in the SST as well as longer term climatic variations. The spectral analysis also shows periodic features in PSD levels around 15 to 31 Hz. The Intergovernmental Panel on Climate Change concluded in 2014 that the increase in temperature has mostly affected the upper (0 - 700 m) ocean while assessing the impact of climate change in the deep sea (> 1000 m) is a challenging task due to the difficulty of gathering long-term comprehensive data. This link between sound pressure levels at 1-km depths and the surface temperature of the ocean is particularly important. Sound is an Essential Ocean Variable, and a key factor to better understand the Earth’s climate system.

Original languageEnglish
Title of host publicationProceedings of 7th Underwater Acoustics Conference and Exhibition, UACE 2023
EditorsM. Taroudakis
PublisherI.A.C.M, Foundation for Research and Technology - Hellas
Number of pages6
Publication statusPublished - 30 Jun 2023
Event7th Underwater Acoustics Conference and Exhibition, UACE 2023 - Kalamata, Greece
Duration: 25 Jun 202330 Jun 2023

Publication series

NameUnderwater Acoustic Conference and Exhibition Series


Conference7th Underwater Acoustics Conference and Exhibition, UACE 2023


  • CTBTO monitoring
  • ocean ambient noise
  • statistical trends

ASJC Scopus subject areas

  • Geophysics
  • Oceanography
  • Environmental Engineering
  • Acoustics and Ultrasonics


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