Low-frequency wind-generated ambient noise source levels

Measurements of ambient noise (30–800 Hz) useful in characterizing the wind-generated component have been obtained in the low ship density Southern Hemisphere. Source levels that characterize the frequency and wind speed dependence of this noise have been obtained by Burgess and Kewley using vertical noise directionality data and had been implemented in a diagnostic computerized noise model. Northern Hemisphere vertical noise directionality data have been examined, processed for source level, and compared to these results. These data and other data summaries, when taking a two-mechanism viewpoint, are found to be consistent with respect to wind speed and frequency dependence. When a dipole source model, based on the possible physical mechanism of sound production, is used, a set of consistent source levels for wind-dependent noise are realized from the several data sets examined.