Sound travels fast, and far, underwater- which is why you can't tell direction, only intensity, while diving.
The good news is that intensity varies with respect to angle - when your ear is 90 degrees to the sound source, the intensity is greater than at 0 or 180 (or 270). So, next time you hear a boat, turn your head from side to side and spend 10 seconds analyzing the sound intensity. At least, you'll know where to look when you surface.
Fleshy,
You might consider using discretion re: verbal reprimands. If I have a point of contrast with my buds, I take it to the PM.