Measurements of Ambient Noise during Extreme Wind Conditions in the Gulf of Mexico

The Littoral Acoustic Demonstration Center (LADC) deployed three Environmental Acoustic Recording System (EARS) buoys in the northern Gulf of Mexico during the summer of 2002 (LADC 02). The hydrophone of each buoy was approximately 50 m from the bottom in water depths of 645 m to 1034 m. During LADC 02 Tropical Storm Isidore and Hurricane Lili passed within approximately 73 nmi and 116 nmi, respectively, west of the EARS buoys. The proximity of these storm systems to the EARS buoys, in conjunction with wind speed data from three nearby National Data Buoy Center weather (NDBC) buoys, allows for the direct comparison of underwater ambient noise levels with high wind speeds. These results are compared to the G. M. Wenz spectra at frequencies from 1 kHz to 5.5 kHz. Anomalously high levels of ambient noise may be due to banding effects of the storms. Results of the ambient noise analysis will be presented. (Research supported by ONR PE62435N).