According to the literature review, the work in the shallow sea of the low-frequency active sonar
mainly faces the following problems.
"But this activity entails deafening sound: even one low-frequency active sonar
loudspeaker can be as loud as a twin-engine fighter jet at takeoff."
Low-frequency active sonar
technology, such as the surveillance towed-array sensor system, may be an effective alternative to passive detection, but is politically disadvantaged because it has been reported to harm marine mammals.
Humpback whales lengthen their calls during playback of low-frequency active sonar
, and in the July 17, 2003 Nature, researchers in the Netherlands reported that city birds near heavy traffic tend to sing at higher pitches (SN: 7/19/03, p.
National Marine Fisheries Service and the Navy, BMMS asserted: "Mitigation of naval activities during peacetime appears to be the only reasonable solution to this problem." While the Navy says it will try to avoid the deadly combination of factors in the future, it is still trying to get approval to deploy its revolutionary Low-Frequency Active Sonar
. This system emits far-traveling sounds as loud as a jet engine for more than a minute at a time to find new, quieter submarines.
In Exposure Guidelines for Navy Divers Exposed to Low-Frequency Active Sonar
, a 1996 report by F.
To improve detection of the new breed of quieter submarine, the Navy hopes to employ a low-frequency active sonar