2023_programme: The contribution of climate change on the propagation of shipping noise in the North Atlantic Ocean

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  • Session: 21. Underwater Noise - Modelling and Measurements
    Organiser(s): Alexander Gavrilov
  • Lecture: The contribution of climate change on the propagation of shipping noise in the North Atlantic Ocean
    Paper ID: 1933
    Author(s): Possenti Luca, Reichart Gert-Jan, de Nooijer Lennart, Lam Frans-Peter, de Jong Christ, Colin Mathieu, Binnerts Bas, Boot Amber, von der Heydt Anna
    Presenter: Possenti Luca
    Abstract: Since the industrial revolution oceans have become substantially noisier. The main source of this noise increase is shipping which is exacerbated by the altering of oceans due to climate change. In the coming century, we will witness changes in seawater temperature, ice melting, a decrease in ocean pH and a rise in the frequency of storms. \nTo explore the impact of climate change on shipping noise, we modelled sound at 125 Hz from a single ship navigating in deep waters. We calculated the propagation losses with the parabolic equation acoustic model RAM taking into account sound absorption and sound speed profiles. The worldwide effect of climate change was explored as the difference between 2022 and 2099 assuming two different climate scenarios (Shared Socioeconomic Pathways 8.5 and 4.5) for atmospheric and seawater temperature, salinity, pH and wind speed.\nThe results show a global increase of sound speed at different depths (from 5 to 640 m) except for the North Atlantic Ocean and the Norwegian Sea where in the upper 125 m sound speed will decrease by up to 40 m s-1. This decrease in sound speed results is consistent in the two climate scenarios where a new sub-surface duct is visible in the upper 300 m allowing ship noise to propagate over large distances (>500 km). We relate the appearance of this new sub-surface duct with the slowing down of the Atlantic Meridional Overturning Circulation (AMOC.) The increase of sound speed in other regions will not have a significant effect on sound propagation that will remain similar to those of the current day. Also, at 125 Hz sound absorption will decrease by more than 50 % but the effect on the PL will be negligible (1 dB).
  • Corresponding author: Dr Luca Possenti
    Affiliation: NIOZ
    Country: Netherlands
    e-mail:

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