Physics-informed and machine learning-enabled retrieval of ocean current speed from flow noise

The Journal of the Acoustical Society of America, Journal Year: 2025, Volume and Issue: 157(2), P. 1084 - 1096

Published: Feb. 1, 2025

Episodes of exceptionally strong near-bottom currents were encountered at depths over 2500 m in a 52-day deployment moored autonomous acoustic noise recorders (MANRs) the Atlantis II Seamounts Northwest Atlantic. A correlation is found between current speed and intensity, especially infrasonic frequencies below 20 Hz. Flow ambient sound, including shipping noise, made comparable contributions to measured intensity but had distinct spectral properties. This paper explores way identify quantify differences flow sound pressure fluctuations by hydrophone find statistical characteristics which contain robust information about speed. regression tree machine learning model was developed relate features directly speeds. By training using data from MANR equipped with meter, time series obtained 1-min resolution another MANR, where only available. Accuracy inferred speeds confirmed comparing dependence spectra on two MANRs.

Language: Английский

Spatial observations of low-frequency acoustic propagation near isolated seamounts using an autonomous surface vehicle

JASA Express Letters, Journal Year: 2025, Volume and Issue: 5(4)

Published: April 1, 2025

This work demonstrates the feasibility of using autonomous surface vehicles equipped with a shallow towed acoustic module (TAM) to survey spatial variability low-frequency propagation across complex bathymetry, such as Atlantis II seamounts in Northwest Atlantic. The abrupt seamount topography is found significantly influence TAM's recordings chirp transmissions (500–600 Hz band) from bottom-moored source ∼30 km by notably causing blockage in-plane paths and reverberation arrivals displaying three-dimensional effects, confirmed synthetic aperture beamforming. Ray tracing simulations are compared these observations based on data-assimilated ocean model.

Language: Английский

Deep-water ambient sound over the Atlantis II seamounts in the Northwest Atlantic

The Journal of the Acoustical Society of America, Journal Year: 2024, Volume and Issue: 156(4), P. 2687 - 2700

Published: Oct. 1, 2024

Ambient sound was continuously recorded for 52 days by three synchronized, single-hydrophone, near-bottom receivers. The receivers were moored at depths of 2573, 2994, and 4443 m on flanks in a trough between the edifices Atlantis II seamounts. data reveal power spectra intermittency ambient intensity 13-octave frequency band from 0.5 to 4000 Hz. Statistical distribution exhibits much heavier tails than expected exponential throughout observations. It is established with high statistical significance that are incompatible common assumption normally distributed noise deep water. Spatial variability observed appears be controlled seafloor properties, bathymetric shadowing, nonuniform sources sea surface. Temporal dominated changes wind speed position Gulf Stream relative experiment site. increases 4–10 dB when axis within 25 km intensification attributed effect current surface wave breaking.

Language: Английский