It may well be the jpg compression but there is so little detail in the black background that I would get rid of as much as possible to let that incredible foreground texture sing a little more. And, perhaps lift those blacks a tad?
Hmmm… on my screen the background is just bright enough to make me wonder what’s there, but not bright enough to show me, so I find it distracting. I’d also clone out those two OOF bits on the horizon, near the left edge. I love the colours in the foreground ice, but to me the composition looks like the greenish bit is pushing the bluish bit out of the frame and I wonder what’s to the right. (those are highly technical terms, BTW). Without being there, sometimes you get what you can get.
Mike Nelson Pedde