I suspect that because the water rises into a hole, it’d carry the air in its movement. Solid ice is at a stable height, but water (and air) are always finding the exits.
@Darth_Innocuous - you are a braver soul than I, but I’ll up my hoody game and see if it helps. I’ve got a 7mm hood and boots, but it’s my torso that seems to feel chill the fastest, even in a hybrid drysuit. Hands, too, of course, because you can’t lay line with bulky gloves.
