台风“启德”对南海深海海洋环境噪声特性的影响研究
Effects of typhoon "KAI-TAK" on deep ocean ambient noise in the South China Sea
-
摘要: 研究台风“启德”经过南海北部对南海深海海洋环境噪声的影响,表明台风导致的风速增减、降雨强弱以及形成的长波涌浪均会影响海洋环境噪声级的大小变化,海洋环境噪声显著受到台风的影响。相同风级下,台风期间海洋环境噪声级与风速的相关性明显好于非台风期间。分析测量的415 h海洋环境噪声数据与风速、波高的相关性,频率大于300 Hz时,海洋环境噪声级与风速的互相关系数大于0.5,达到中度相关;频率大于630 Hz时,互相关系数介于0.8和0.9之间,达到高度相关;频率大于300 Hz时,海洋环境噪声级与风速的相关性好于海洋环境噪声级与波高的相关性。南海海洋环境噪声10~20 Hz的次声频与风速的相关性差,是因为南海航运繁忙,该频段的海洋环境噪声会受到航船噪声的影响,即使台风期间也不例外。Abstract: By investigating the effects on deep ocean ambient noise of typhoon "KAI-TAK" which passed the north area of the South China Sea, it is shown that the wind speed, the rainfall intensity and the long wave swell caused by typhoon affect the ocean ambient noise significantly. The correlation between the ocean ambient noise and the wind speed during the typhoon is much better than that in the non-typhoon period in the same Beaufort scale. Analysis of the correlation between the 415 h ocean ambient noise measured data and wind speed shows that, when the frequency is greater than 300 Hz, the correlation coefficient between the ocean ambient noise and the wind speed is greater than 0.5. achieving a moderate correlation: when the frequency is greater than 630 Hz, the correlation coefficient is between 0.8 and 0.9, achieving a high degree of correlation. The correlation between the ocean ambient noise and the wind speed is better than that between the ocean ambient noise and the significant wave height when the frequency is greater than 300 Hz. The correlation between the ocean ambient noise and the wind speed in infrasonic band from 10 Hz to 20 Hz is poor in the South China Sea., because the shipping is busy in this sea area and the ocean ambient noise is contaminated by the ship noise even during the typhoon.