Analysis of the vertical directionality of ambient noise: SPICE04 experiment measurements and model simulations.

Abstract

The SPICE04 experiment provided a unique opportunity to observe the ambient noise in the North Pacific [Worcester et al., J. Acoust. Soc. Am. 120(5), p. 3020]. Receptions on two 700-m segments of a deep vertical line array (DVLA) facilitate measurements of the vertical directionality of the noise above and below the surface conjugate depth. Several authors have proposed models for deep ocean noise, e.g., the spatial harmonic model developed by Cox [J. Acoust. Soc. Am. 54(5), pp. 1289–1301] and the normal mode model developed by Kuperman and Ingenito [J. Acoust. Soc. Am. 67(6), 1988–1996] and extended by Perkins et al. [J. Acoust. Soc. Am. 93(2), pp. 739–752]. The simulated data provided by these models can be used to assess the effects of array tilt on estimates of vertical directionality. In this talk, we first analyze the impact of tilt for the DVLA using the array element positions measured during the experiment. Then we compare the SPICE04 noise estimates for the two 700-m array segments and the relevant model output. [Work sponsored by ONR.]