Results of a Survey of the Acoustic Conditions in the Northern Gulf of Ob

Abstract: The article presents the results of acoustic monitoring in the northern part of the shallow-water Gulf of Ob (Ob River estuary, an embayment in the Kara Sea). Vessel-generated noise and communication signals from marine mammals are identified among acoustic sources. Sounds produced by beluga whales are subjected to quantitative analysis using a convolutional neural network. A model for inhomogeneous geoacoustic waveguide characteristic of this area is inferred from the data of a dedicated survey using an air gun as a low-frequency pulse source. A conclusion is drawn about the high level of attenuation of low-frequency sound during propagation. Based on numerical modeling, the measurement results are extrapolated to other sites of the study area that potentially have sources of anthropogenic noise.