Well, we're working with different software, so I'm not sure if photoshop has something that would work, but I'd try robA's wispy displace technique in Gimp (for the transition from ice to water). It's a displace map with the map set to a noise layer, 20x -20y then -20x 20y. Although what you have is decently wispy already, I think. A good test is to wrap it onto a sphere afterwards and see if it looks right. I've always found it so difficult to do the poles in an equi. projection that I usually give up and use a different one