Talk:Phantom bottom

Information from On A Farther Shore

In case anyone wants to expand the article in the future, here is the info I originally put in the article request for this page.

Here's a definition. I am reading a book called "On a Farther Shore" by William Souder (2012). A biography of Rachel Carson. He mentions (page 130) that early sonar equipment found a baffling "phantom bottom" everywhere around the world. This was at a depth of around 250 fathoms, even when measurements were taken in waters where the true depth of the ocean (as gauged by rope/line measurements) were known to be much deeper. This "deep scattering layer" vanished at night time. "Researchers eventually determined that the phantom bottom was alive and comprised a variety of fish, squid, and tiny marine creatures such as krill that make a daily migration out of the depths at nightfall to feed on the surface. Biologists already knew that marine life tended to congregate at the surface after dark, as netting operations were more successful at night." ... "...the global scale of this mass-movement of animal life was amazing, as the community of marine organisms within this moveable realm would ultimately turn out to be the largest biomass on earth." Stuart mcmillen (talk) 06:14, 21 June 2013 (UTC)