Underwater noise reduction in the Slovenian Sea due to restriction measures during COVID-19 pandemic
- Authors: Andreja Popit, Luka Čurović
- Citation: Acta hydrotechnica, vol. 39, no. 70, pp. 15-25, 2026. https://doi.org/10.15292/acta.hydro.2026.02
- Abstract: The aim of this study was to analyze the reduction of underwater noise levels measured in the Slovenian Sea during the year 2020, when restriction measures due to the declared COVID-19 pandemic were applied to shipping. Annual average values of the sound level in 1/3-octave bands, one centered at 63 Hz and the other at 125 Hz, were calculated from the measured sound levels in each year according to the methodological standards for monitoring and assessment. This study shows that underwater noise levels in the Slovenian Sea in 2019 and 2020 were reduced compared to 2019, because of the reduction in ship traffic due to COVID-19 pandemic restriction measures. Furthermore, the reduction of underwater noise levels in 2020 was also confirmed by modelling using a parabolic equation method based on the ship traffic data from the Automatic Information System. Modeled values were influenced mostly by the speed of the ships. These findings indicate that the application of simple operational measures, such as rerouting and speed limitation, might prove useful to make seas and oceans quieter in the future.
- Keywords: Underwater noise, reduction, COVID-19 pandemic
- Full text: a39ap.pdf
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