Emergence of the Green’s Functions from Noise and Passive Acoustic Remote Sensing of Ocean Dynamics

1. To demonstrate theoretically emergence of the deterministic Green’s functions (GFs) from noise sources distributed in a volume and on boundaries in inhomogeneous, fluid-solid environments with dissipation. 2. To investigate a relation between the deterministic GFs and a two-point correlation function of noise in a low-frequency regime where stationary-point arguments become inapplicable. 3. To quantify degradation of performance of passive remote sensing techniques due to ocean surface motion and other variations of underwater sound propagation conditions in time. 4. To retrieve flow-induced non-reciprocity of acoustic phase and amplitude of the deterministic GFs from cross-correlation of diffuse sound fields generated as a result of scattering by inhomogeneities in the water column and/or by seafloor and sea surface roughness. 5. To determine accuracy of current velocity measurements using acoustic travel time nonreciprocity retrieved from a two-point noise cross-correlation. 6. To evaluate, for shallowand deep-water scenarios, optimal parameters of a passive acoustic system for ocean temperature and current velocity measurements using cross-correlation of ambient noise and/or sound fields generated by sources of opportunity.