Underwater noise level predictions of ammunition explosions in the shallow area of Lithuanian Baltic Sea

2019 ◽  
Vol 252 ◽  
pp. 1311-1317 ◽  
Author(s):  
Donatas Bagočius ◽  
Aleksas Narščius
Keyword(s):  
Baltic Sea ◽  
Noise Level ◽  
Underwater Noise ◽  
Shallow Area

scholarly journals Underwater Noise Modeling in Lithuanian Area of the Baltic Sea

2017 ◽  
Vol 9 (4) ◽  
pp. 393-399
Author(s):  
Donatas Bagočius ◽  
Aleksas Narščius
Keyword(s):  
Baltic Sea ◽  
Ambient Noise ◽  
Ecological Impacts ◽  
Noise Model ◽  
Underwater Noise ◽  
Marine Strategy Framework Directive ◽  
Noise Measurements ◽  
Shallow Area ◽  
The Baltic ◽  
Sea Area

Along with rising awareness of public and scientific societies about environmental and ecological impacts of underwater noise, the need for underwater noise modelling in the shallow Lithuanian area of Baltic Sea emerged. Marine Strategy Framework Directive issues regarding underwater noise indicators refers to possibility of evaluation of Good Environmental State using underwater noise measurements as well as possibility to model underwater noise. Main anthropogenic underwater noise contributor in the Seas is the shipping lanes as known due to date, with no exclusion of Lithuanian Baltic Sea area. In this manuscript, it is presented the methods of development of simplistic underwater ambient noise model purposed for computation of underwater soundscape in shallow area of the Lithuanian Baltic Sea.

scholarly journals Underwater noise level in Klaipėda Strait, Lithuania

Baltica ◽  
2013 ◽  
Vol 26 (1) ◽  
pp. 45-50 ◽  
Author(s):  
Donatas Bagočius
Keyword(s):  
Noise Level ◽  
Underwater Noise

scholarly journals Correlation between Underwater Noise and Sea Level at Ieodo Ocean Research Station

2020 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
Seong Hyeon Kim ◽  
Bok Kyoung Choi ◽  
Byoung-Nam Kim
Keyword(s):  
Sea Level ◽  
Correlation Coefficient ◽  
Noise Level ◽  
High Tide ◽  
Research Station ◽  
Time Lags ◽  
Underwater Noise ◽  
Noise Levels ◽  
Wavelet Coherence Analysis ◽  
And Sea Level

To investigate the correlation between underwater noise and sea level, data collected at Ieodo Ocean Research Station (from 15 May to 27 August 2013) were analyzed. Temporal variations in the overall level of underwater noise were similar to those in sea level. The average underwater noise levels at frequencies below 50 Hz were 99.0–106.6 dB during spring tides and 78.4–90.2 dB during neap tides, with a difference of 12.6–20.6 dB. When low-pass filtering at six hours was applied to the absolute value of sea level, a high correlation coefficient of 0.7 for its association with underwater noise was obtained. This strong correlation could indicate flow noise caused by currents. Underwater noise levels around the frequency of 16 Hz were relatively strongly correlated with sea level (correlation coefficient of 0.71). Wavelet analysis of the overall level of underwater noise showed strong periodicity at 0.25, 0.50, 1.0, 16.0, and 30.0 days, as well as characteristics of a tidal constituent. In wavelet coherence analysis, the overall level at a period of 0.25 days exhibited a phase difference of −90 degrees relative to sea level. This finding indicates that the noise level peaks at 1.5 h before the high tide or low tide, which was confirmed in the correlation analysis of noise level and sea height with various time lags. This study shows that the overall level of underwater noise from ebb currents is higher than that from flood currents due to differences in current velocity.

scholarly journals Modelling of underwater noise emissions by ships in Klaipėda Strait, Lithuania

Baltica ◽  
2021 ◽  
pp. 148-156
Author(s):  
Donatas Bagočius ◽  
Olga Anne ◽  
Aleksas Narščius
Keyword(s):  
Baltic Sea ◽  
Sound Pressure ◽  
Curonian Lagoon ◽  
Underwater Noise ◽  
Noise Levels ◽  
The Baltic Sea ◽  
Area Of Interest ◽  
Sound Pressure Levels ◽  
The Baltic ◽  
Harbour Area

One of the United Nations Sustainable Development Goals regarding “conservation and sustainable use of the oceans, seas, and marine resources” emphasizes the urgency of eliminating harmful effects on the sea and its biota, where the role of anthropogenic activities is crucial. The global trend of merchant shipping is increasing, thus enlarging underwater noise levels. As a result, greater noise can harm aquatic animals in their habitats. In the Baltic Sea, the underwater sound pressure levels are now being evaluated utilizing noise measurement, modelling, and mapping. In areas such as narrow ship passages, namely lagoons, channels, or straits, the ambient underwater noise modelling becomes very complex, even though these EU inland waters are regarded by legislation as part of the marine basin. For instance, the Klaipėda Channel (Klaipėda Strait), connecting the Baltic Sea and the Curonian Lagoon, is regarded by the national Lithuanian legislation as part of marine waters, where the environmental status should be evaluated according to the EU Maritime Strategy Framework Directive. In this narrow channel, an alternative to the modelling of ambient sound pressure levels can be applied to understand the long-term trends of vessel-sourced noise emissions. In this paper, an example of application of ship noise emission modelling for a narrow Klaipėda Harbour area is presented, along with the results obtained throughout 2015–2017. The modelled noise levels in the harbour area reached the median levels of 112.5 dB in 2015 and 102.6 dB re 1 µPa2 in 2017. The maximum emitted instantaneous sound pressure levels by ships reached 173.7 dB in 2015 and 179.4 dB re 1 µPa2 in 2017 in the area of interest.

scholarly journals Offshore Installation Activities and Marine Mammals’ Protection

2018 ◽  
Vol 54 (1) ◽  
pp. 119-128
Author(s):  
Iva Šebelja ◽  
Igor Kegalj ◽  
Luka Traven
Keyword(s):  
Noise Level ◽  
Marine Mammals ◽  
Adriatic Sea ◽  
Limited Area ◽  
Visual Methods ◽  
Underwater Noise ◽  
Northern Adriatic Sea ◽  
Northern Adriatic ◽  
Technical Performance ◽  
Normal Life

During installation activities of four platforms in the Italian sector of the northern Adriatic Sea, in addition to the technical performance, special attention had to be dedicated to the protection of marine mammals from the noise produced. Acoustic and visual methods were applied 24 hours a day during the months of installation to monitor the movement of marine mammals. Project installation activities, especially piling and mooring, raise underwater noise level concentrated in a relatively limited area, which can interfere with the normal life of marine mammals. The goal of the research conducted in the framework of this paper is to describe the working methodology, the measures of marine mammals’ protection and to present the final monitoring results.

scholarly journals Modeling of ships as a source of underwater noise

2018 ◽  
Author(s):  
Jukka-Pekka Jalkanen ◽  
Lasse Johansson ◽  
Mattias Liefvendahl ◽  
Rickard Bensow ◽  
Peter Sigray ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Noise Source ◽  
Source Model ◽  
Assessment Model ◽  
Alternative Methods ◽  
Underwater Noise ◽  
Traffic Emission ◽  
Activity Data ◽  
Ship Traffic ◽  
The Baltic

Abstract. In this paper, a methodology is presented for modeling underwater noise emissions from ships based on realistic vessel activity in the Baltic Sea area. This paper combines the Wittekind noise source model with the Ship Traffic Emission Assessment Model (STEAM) in order to produce regular updates for underwater noise from ships. This approach allows the construction of noise source maps, but requires parameters which are not commonly available from commercial ship technical databases. For this reason, alternative methods to fill in the required information were necessary. Most of the parameters needed contain information which are available during the STEAM model runs, but features describing propeller cavitation are not easily recovered for the world fleet. Baltic Sea ship activity data was used to generate noise source maps for commercial shipping. Containerships and bulk cargo ships were identified as the most significant source of underwater noise, with a significant potential for increasing contribution to future noise emissions.

Phosphate exchange across the sediment-water interface under oxic and hypoxic/anoxic conditions in the southern Baltic Sea

2011 ◽  
Vol 40 (2) ◽  
Author(s):  
Katarzyna Łukawska-Matuszewska ◽  
Dorota Burska
Keyword(s):  
Baltic Sea ◽  
Water Interface ◽  
Organic Form ◽  
Southern Baltic Sea ◽  
Phosphorus Forms ◽  
Shallow Area ◽  
Phosphate Flux ◽  
Southern Baltic ◽  
Phosphate Exchange ◽  
Phosphorus Turnover

AbstractBenthic fluxes of phosphate and phosphorus distribution in sediments from the southern Baltic Sea were investigated in spring and autumn in 2005 and 2007–2010. Strong spatial variability of phosphate fluxes was observed across the sediment-water interface. The highest values of phosphate flux from sediment (up to 37 μmol m−2 h−1), resulting from the high mineralization rate of organic matter and rapid phosphorus turnover due to macrofaunal activity and hydrodynamic conditions, were observed in the shallow area at depths ranging from 50 to 69 m. The rate of phosphate exchange in the transportation and accumulation bottom area with the water depth ≥72 m was several times lower (2.12–6.22 μmol m−2 h−1). In continuously hypoxic or anoxic sediments, phosphorus was preserved in the refractory organic form, and sediments were depleted of redox-dependent phosphorus forms. In shallow area with well oxygenated near-bottom water, phosphorus was present mainly in the calcium-bound form.

A REVIEW OF PRACTICAL METHODS FOR REDUCING UNDERWATER NOISE POLLUTION FROM LARGE COMMERCIAL VESSELS

2021 ◽  
Vol 156 (A2) ◽  
Author(s):  
R C Leaper ◽  
M R Renilson
Keyword(s):  
Noise Level ◽  
Ambient Noise ◽  
Noise Pollution ◽  
Underwater Noise ◽  
Ambient Noise Level ◽  
Noise Impact

The paper provides an interesting and rather complete overview of the reasons for reducing shipping noise and the possible ways to achieve this. It is in particular interesting to note that the majority of noise impact is probably caused by the noisiest 10% of ships, and that the ambient noise level in the oceans increased by around 20 dB compared to pre-industrial conditions.

Sign in / Sign up

Export Citation Format

Share Document