I'm studying internal seiching - which is a large standing wave that occurs on the interface between warm and cold water in a lake. These are waves act on the entire length of a lake at once, and can amplitudes of 10's of meters. They are often one of the biggest drivers of water movements within a lake. While people have been studying them for decades, and in general they're well understood, there's still work to be done once the shape of the lakes starts becoming more complex.
For books, I'd recommend "Limnology" by Wetzel as a starting off point. I've still only read the first 4 or 5 chapters because that's the only part that pertains to physical limnology. I should read the rest of the book so I have a better understanding of the biological/ecological aspects of these systems.