As you get low you basically end up squishing the air below you which basically will give more lift in the last few feet than above it, the side effect over water is that it disturbs the surface.
Ever noticed that floating feeling when coming into LGW Or LHR in the last few feet it's not all hold off on the pilots stick.
To pick out a camouflaged aircraft is difficult, so when you’re above playing the prowler, you look for the shadow far more distinctive to see than the actual aircraft, closer you get to the ground the more chance you have of covering your own tracks (shadow).
Fighter tactics part I. Important safety tip “don’t let the fekkers find you”
Ground Effect can also describe grazing to the face & body when you pissed as a pudding and fall over the garden wall onto the drive or pavement
__________________