So graphing the ocean floors using sonar is not anything new. But what are the limits to sonar?

Would it be possible for a regular sonar device to emit sounds that are strong enough to penetrate through polluted waters? And if they can, how much pollution is needed to block the sonar completely? And by pollution I mean plastic waste (bottles, bags, etc).

Also, would highly populated waters be a problem? I'm talking about corals, fish, algae, and others. I'm pretty sure just one fish wouldn't do much, but what about a whale? Or a swarm of fish?


1 Answer 1


Using sonar to map the ocean floor is not usually affected by pollution or by the occasional fish, if it's a normal herring or cod sized fish. Plastic pollution usually floats or sinks so it isn't a problem. A fish the size of a basking shark would show up on the sonar, but it wouldn't be a problem. Large shoals of fish also show up, but it would have to be a very large shoal indeed to interfere with mapping the ocean floor. There are seasonal shoals large and continuous enough to do this, but only at certain times of the year in a very few locations where they are on migration in their billions. I have never heard of one causing problems for a vessel whose mission was to map the ocean floor or search for a sunken ship. Sonar is sometimes used by trawlers to search for shoals of fish.

  • 1
    $\begingroup$ Sonar is the basis of fishfinders used by recreational fishermen to find shoals and even individual fish, but they also still show the bottom. The noise from plastics, minor, and fish would be filtered out by the software on the sonar. $\endgroup$
    – user824
    Commented Aug 21, 2019 at 0:00

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.