[Lower Deck]

do you know why the locations are varying? i am guessing its nothing suspicious just the signal in water but i would like to know. no doubt as they get closer and closer its gets more accurate...is that how it works?

A lot of things affect the way sound moves through water. Changes in depth, temperature, and salinity will cause sound to move faster or slower and curve the direction in which it travels. Layers of warmer and colder water can trap the sound, like trying to transmit it through the roof of your house. As sound curves upwards it converges and can literally bounce off the surface only to be detectable again miles away. These don't prevent you from narrowing down the location of the sound source but they do make it more challenging.

[Irishguy]

thanks — didnt realise so many variables in it. much appreciated.