XPost: sci.physics.acoustics, alt.sci.physics.acoustics, sci.geo.oceanography   
   XPost: rec.audio.pro   
   From: kludge@panix.com   
      
   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."   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)