东沙海域海洋环境噪声特性分析及其与风速的相关性研究

Characterization of ocean ambient noise and its correlation with wind speed on Dongsha sea areas

本研究利用亚洲海国际实验南海区所获取的海洋环境噪声数据,研究了2001年5月3日0时至5月17日0时海洋环境噪声的时频特性.实验期间有热带风暴西马仑经过,导致海面风速和风生海洋环境噪声随西马仑的逼近和远离出现了显著的升降.以1250Hz的海洋环境噪声为例,海洋环境噪声级在这一期间内有一个明显的升高、稳定和缓慢下降的过程.结合再分析风速数据研究海洋环境噪声级与风速的相关性,结果表明,在较高频1250Hz处,海洋环境噪声级与风速的互相关系数r为0.50;在较低频50-400Hz处,两者的互相关系数r在-0.20-0.20之间.此外,本研究利用噪声级与对数风速之间的线性关系式,将海洋环境噪声级与实验过程中海面风速数据做回归分析,确定拟合系数,将此系数用于反演估计海面风速,反演误差在5%-20%之间.

In this paper,the time-frequency characteristics of ocean ambient noise from 0： 00 on May 3 to 0： 00 on May 17 2001 were studied used the data obtained from the Asian Seas International Experiment. There was a tropical storm Cimaron occurred during the experiment,thus the approaching and leaving Cimaron caused sea surface wind and wind-generated ocean ambient noise rise and fall obviously. For instance,the ocean ambient noise level at 1 250 Hz showed a period of obvious increasing,stabilization and slowly decreasing. The correlation between ocean ambient noise level and wind speed based on the reanalysis data shows that at high frequency 1 250 Hz the correlation between the ocean ambient noise level and the wind speed is 0. 50. At the low frequency 50 - 400 Hz,the correlation between the ocean ambient noise level and the wind speed is- 0. 2 - 0. 2. In addition,based on a linear relation between ambient noise level and logarithmic wind speed the regression analysis between ambient noise level and wind speed was performed and fitting coefficient,with inversion error between 5% - 20%,established for the inversion of surface wind speed.