Influence of Absorption in Low Salinity Sea Water on Nonlinear Wave Propagation

Interaction of finite amplitude wave in nonlinear medium, for instance the sea water, is the phenomenon finding often practical application in underwater observation and communication. Conditions of finite amplitude wave generation and propagation in a low salinity sea water are analysed basing on data taken for the purpose in the Baltic Sea. Variations in the conditions caused by seasonal changes in hydrological conditions are discussed. Primary waves of frequency range from 20 kHz to 150 kHz are taken into account. The aim of the paper is to characterise the influence of absorption of low salinity seawater on the nonlinear wave propagation. The paper contains the results of research based on hydrological in situ measurements in the Southern Baltic.