Underwater noise emissions from ships during 2014-2020

This paper reports trends in the input of underwater noise source energy emission from global shipping, based on bottom-up modeling of individual ships. In terms of energy, we predict the doubling of global shipping noise emissions every 11.5 years, on average, but there are large regional differences. Shipping noise emissions increase rapidly in Arctic areas and the Norwegian Sea. The largest contributors are the containerships, dry bulk and liquid tanker vessels which emit 75% of the underwater shipping noise source energy. The COVID-19 pandemic changed vessel traffic patterns and our modeling indicates a reduction of -6% in global shipping noise source energy in the 63 Hz 1/3 octave band. This reduction was largest in the Greenland Sea, the Coastal Waters of Southeast Alaska and British Columbia as well as the Gulf of California, temporarily disrupting the increasing pre-pandemic noise emission trend. However, in some sea areas, such as the Indian Ocean, Yellow Sea and Eastern China Sea the emitted noise source energy was only slightly reduced. In global scale, COVID-19 pandemic reduced the underwater shipping noise emissions close to 2017 levels, but it is expected that the increasing trend of underwater noise emissions will continue when the global economy recovers.

Automated summary

This paper reports on trends in underwater noise emissions from global shipping, based on individual ship modeling. The research predicts a doubling of noise emissions every 11.5 years, with significant regional differences. Containerships, dry bulk, and liquid tanker vessels contribute the most to underwater noise, accounting for 75% of the total energy emitted. The COVID-19 pandemic led to a temporary reduction in global shipping noise emissions, particularly in specific regions, but it is expected that the increasing trend will continue as the global economy recovers.