Okay, this seems like the sort of thing that surely must have come up before, but I've searched around for it and have been unable to find anything. (Admittedly, I only searched here and in the Pathfinder rules; it's possible there was a ruling on it somewhere regarding 3.5E, but if so that wouldn't necessarily have been binding in Pathfinder anyway.)
So, I guess I'll ask here. What happens if you cast freezing sphere underwater?
The rules for freezing sphere say that if it "strikes a body of water or a liquid that is principally water (not including water-based creatures), it freezes the liquid to a depth of 6 inches in a 40-foot radius." But striking a body of water isn't the same thing as being cast underwater. Would it freeze the outer 6 inches of its spherical area of effect? Would it just freeze at the caster's fingertips the moment it was cast and thus be rendered useless? (That last possibility seems silly, and I hope it isn't the case, but it is a conceivable ruling given the spell's description.)
The rules for aquatic terrain say that "[s]ome spells might function differently underwater, subject to GM discretion." Freezing sphere seems logically like one of those spells that should definitely work differently underwater... I'm just not sure how it should work underwater.
Is there a ruling on this already somewhere that I missed? Like I said, it seems like the sort of thing that should have come up by now, so it seems unlikely I'm the first one to have asked this question, but I couldn't find anything...