Characterization of underwater noise in the Baltic Sea

Abstract

Abstract Concern over the possibly harmful effects of increased levels of underwater ambient noise in the Baltic Sea has led to a number of large-scale EU projects investigating the current situation of the underwater soundscape. This thesis details an attempt at modelling the characteristics of the underwater noise at two positions in the Baltic Sea. Specifically spectral curves of the most common noise sources are described and presented in Wenz diagrams. The noise sources include: ships, piling, active sonar, wind and precipitation. The curves were created using available data for ship positions and weather together with audio data recorded using hydrophones laid out for the duration of 2014. Keywords: underwater acoustics, environmental noise, SHEBA project, BIAS project, The Swedish Defense Research Agency, Baltic Sea, Wenz curves, shipping, infrastructure v