Review To 3D Mapping Of Low Frequency Ambient Shipping Noise.

This paper states that the standard modes of signal transmission underwater are acoustic waves and a large majority of marine life uses sound waves for regular movement. Therefore, the classification and analysis of sources of underwater noise becomes imperative. The study classifies the noise in context of ships into following types: (1) Underwater radiated noise, (2) Noise onboard the ship and (3) Self Noise. Of these, the most important classification, which will also be the subject of this report’s discussion, is underwater radiated noise. This report mainly focuses on noise generated by human shipping activities. This research note aims to present a high-level view on the sources of noise underwater, and then focuses on Underwater Radiated Noise (from human shipping activities). It further presents various existing models for its estimation. The research note suggests that the first step towards dealing with noise is to estimate its sources and level.

1. The primary objective of this research note is study of various techniques modeled so far developing the complete bookmark to three-dimensional version of the sound mapping propagating underwater

2. The research note gives an insight to merits and demerits of each adapted model along with a sample outcome attached for a better understanding of the readers.

3. However, throughout the course of this study, all reference files and documentations used and needed are linked in the end in order to facilitate the replication of such models for further use in future research.

4. Sound propagation noise mapping of an area displays the varying noise levels in a region in the form of a color-coded map, also called heatmap, in accordance with several parameters like bathymetry, temperature, sedimentation and seamounts with microphones like hydrophones.

5. A 3D – mapping of noise underwater can be a source point to further research and studies in various domains and a crucial step in moving towards expanding the understanding of the Underwater Domain.

6. One of the best benefits of 3D mapping is that it provides the latest technical methods for visualization and gathering information.

7. Underwater Noise is measured through hydrophones which are the underwater equivalent of a microphone which measures the sound in the region by factoring the pressure changes in the surrounding.