Just to review:
1. When they say that "the waters above the sea kings home have frozen solid" they're talking about the ocean. At the point that things have gotten cold enough for the world's oceans to FREEZE SOLID everyone on earth is dead.
2. The aptly named Iceberg Head's sole motivation is, and I quote, "I'm going to destroy Atlantis and everyone and everything in it -- just because I'm a cold creature!! Nothing warms me. Nothing!!! NOTHING!!!"
3. He then oddly is afraid that a Hostess Cup Cake will make him "feel happy and warm all over" despite the fact that they aren't a hot food.
4. Even though it effectively murders him, he eats the Hostess Cup Cake anyway and then Aquaman decides to keep his disembodied consciousness as a pet.