Low-frequency ambient-noise measurements in the South Fiji basin

The effect of wind speed on ambient noise has been measured in an experiment carried out in the South Fiji basin. The noise data in the band 15-250 Hz are well correlated with the variations in the local wind speed. The relationship between noise level N and wind speed ν is expressed by N=B+20n log ν. The constants B and n have been estimated by fitting the data using this model. The analysis indicates that there are two types of behavior: for ν>15 kn, a value of n=1.5 is obtained for the entire band, whereas for ν<15 kn, there is no correlation with wind speed observed in the data. The results suggest that there is a delay of 40-120 min for the effect of wind on the hydrophone noise level