Analysis of very low frequency wind driven noise at Ocean Observatories Initiative hydrophones

In the frequency band between 1 and 10 Hz, ambient sound in the ocean has a global pattern in the power spectral density that is driven by local surface gravity waves and is highly correlated to wind speeds. At low frequencies above 10 Hz, other source mechanisms dominate ambient sound. In thispresentation, surface buoy measurements, model estimates, and satellite-based observations of wind speed are compared to spectral levels measured by the five low-frequency hydrophones that are part of the Ocean Observatories Initiative Cabled Array. Features of the spectrogram are categorized and associated with wind observations. The ambient sound spectral levels are linearly separable by wind speed at frequencies below 5 Hz. Lastly, a general frequency-temporal structure of spectral levels due to wind events is presented and discussed. [Work supported by ONR.]