Hurricane classification using a full-field ocean surface noise model

Hurricanes generate noise in the ocean due to wind–wave interaction. The authors have previously discussed the possibility of using this noise to determine the size and strength of the hurricane with a modal model [Wilson and Makris, J. Acoust. Soc. Am. 108 (2000)]. Here the analysis is extended to include a full-field model for surface-generated ocean noise. Unlike previous surface noise models that contained far-field approximations, this full-field model can be used to calculate the acoustic field both inside and outside the hurricane. This full-field model is used to calculate the spatial covariance of the acoustic field generated by a hurricane. This spatial covariance is then used to determine the sound from a hurricane that would be detected by hydrophones and hydrophone arrays. Several examples are presented using single sensors and sensor arrays inside and outside the hurricane to determine the best method for classifying a hurricane. In addition shallow- and deep-water environments are compared to illustrate their effect on the propagation of surface-generated hurricane noise. Also simulations are shown for multiple frequencies to show the filtering effect of the waveguide on the propagation and to determine the optimal frequency for hurricane classification.