[Scott Dorsey]

David Dalton wrote:
In article ,
David Dalton wrote:

What are some strategies for reducing ship, sonar, and
seismic airgun array noise in the oceans in order to
reduce negative effects on marine mammals?

I also posted that to sci.engr and other groups and
there have been a couple of interesting replies
there already.

You know multiposting is kind of rude. It breaks a discussion up. It's
clear you have already crossposted, why not just crosspost to all relevant
groups and drop some of the irrelevant ones?

The thing is, while you can reduce the noise from ships by playing with
hull profiles to improve laminar flow and reduce turbulence, and playing
with prop designs to reduce turbulence and cavitation, there is nothing
you can do about sonar noise.

Because... the whole point of sonar is that it's a loud noise.

What you _can_ do is to move the operating frequency of the sonar to
notes that don't bother mammals, and to do that you need to first find
out what really does bother them. Which nobody really is completely
sure about, it seems.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."