Summary: My research takes a physical oceanographic approach to understanding the interactions between the ocean and ice in both Arctic and Antarctic regions. The polar regions are experiencing rapid changes in the ocean, sea ice, and ice sheets — I focus particularly on the mechanisms by which the ocean melts ice sheets and sea ice, as well as the formation and modification of water masses and ocean circulation unique to polar regions. In-situ observations form the core of my approach, but I also integrate results from numerical experiments and satellite-derived products to develop a comprehensive, multi-faceted understanding of these phenomena.