When large-scale industrial operations are staged in proximity of sensitive natural habitats, it is imperative that the contributions of anthropogenic sound to the overall underwater ambient noise budget be characterized as accurately as possible so that appropriate management measures may be designed and put into practice for the safeguard of the species potentially at risk. Advanced numerical modelling of the aggregate acoustic footprint from multiple sources distributed over an area, as well as the cumulative influence of operations extending over time, does provide a predictive tool that enables noise management considerations to be applied at the planning stage. Examples of this approach include the acoustic modelling of alternative operational scenarios in the planning of offshore construction, so as to stage activities for least aggregate influence, and the forecasting of the cumulative noise footprint from a seismic survey to delineate areas of potential biological impact. A germane requirement to the model-based forecasting is the monitoring of the pre-activity ambient noise landscape and of the combined natural and anthropogenic sound field during industrial work. Such monitoring, which should be spatially and temporally extensive, serves the twin purposes of validating the assumptions and parametric conditions used in the predictive modelling and of providing spot reference measurements to ground truth and calibrate the estimated acoustic fields. An example of this type of monitoring is the basin-scale instrumentation of a sizable region of the arctic shelf seafloor with high-performance autonomous acoustic recorders capable of acquiring several months of digitized sound pressure data at rates adequate for characterization and analysis of natural noise, marine mammal vocalizations, and anthropogenic noise. The examples just outlined will be explored in some detail in this summary paper.
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