What is this sky defect and what is the best way to deal with it?
It's a washed out, cloudy sky to begin with:

The foreground, which I've omitted, contains waves and rocks that look much better after highlighting the photo, but that also highlights the defect in the sky:

What is this called, and what is the best way to fix it? I used the lasso tool to select the sky, followed by inversing the selection and applying highlighting, which worked fairly well (although I can never get the edges precise with the lasso, so imperfections remain where the sky meets water or rocks), but then I realized that I needed to deal with the original defect before doing any other editing. So what is the best way to do that?

