Spatial field shifts in ocean acoustic environmental sensitivity analysis

Area of Science:

• Oceanography
• Acoustics
• Environmental Science

Background:

• Acoustic sensitivity analysis typically compares acoustic fields from reference and perturbed environmental models.
• Perturbations often include spatial shifts (range/depth) and changes to the acoustic field.
• Standard fixed-point sensitivity measures can be misleading due to spatial field shifts.

Purpose of the Study:

• To define and compare fixed-point and field-shift corrected sensitivity measures.
• To address the limitations of standard sensitivity analysis in ocean acoustics.
• To enhance the intuitive understanding of environmental sensitivity.

Main Methods:

• Development of field-shift corrected sensitivity measures.
• Comparison with traditional fixed-point sensitivity measures.
• Application to deterministic and stochastic sensitivity analyses in various ocean environments.

Main Results:

• Field-shift corrected measures provide a more accurate representation of acoustic sensitivity.
• Demonstrated the potential for misleading results with fixed-point measures when spatial shifts occur.
• Illustrated the impact of spatial shifts on sensitivity in both range-independent and range-dependent scenarios.

Conclusions:

• Accounting for spatial field shifts is crucial for accurate ocean acoustic environmental sensitivity analysis.
• The proposed methods offer a more robust approach to quantifying sensitivity to environmental changes and uncertainty.
• This work refines the methodology for assessing the impact of environmental variability on underwater acoustic propagation.