That's a remarkably placid sea given that it's miles from anywhere. Whenever I've stood facing a sea that stretches off for thousands of miles, the waves have always crashed into the cliffs with massive force, even on a calm day. Makes no difference if it's northern California, western England, the islands of the Indian Ocean -- I've been to all of them, and never seen the waves calmly lapping the land edge.
If it's so cold as to maintain a great wall of ice, howcome there aren't ice flows on the water's surface, as you get at the poles?
And where are all the icebergs? Whatever the temperature, the power of the water's movement would erode the edge and rip away chunks of ice. Nor do I see any system for the ice wall to regenerate itself, so in time, the water would wear a gap through the ice wall and ... well, I guess pour off the edge of the earth.
No more water, no more life. We aren't here, and you are not reading this post. You don't exist.
Or maybe there's a little boy on the other side of the ice wall sticking his finger in the hole. The poor lad must be cold!