According to wikipedia, "Physical oceanography is the study of physical conditions and physical processes within the ocean, especially the motions and physical properties of ocean waters.
I would describe it simply that physical oceanography is like "Meteorology," which "is the interdisciplinaryatmosphere that focuses on weather processes and forecasting (in contrast with climatology)." scientific study of the
Another way to put it is, both PO (physical oceanography) and Met (meteorology) are part of "Earth_science."
"Earth science (also known as geoscience, the geosciences or the Earth sciences), is an all-embracing term for the sciences related to the planet Earth.[1] It is arguably a special case in planetary science, the Earth being the only known life-bearing planet. There are both reductionist and holistic approaches to Earth sciences. The formal discipline of Earth sciences may include the study of the atmosphere, oceans and biosphere, as well as the solid earth. Typically Earth scientists will use tools from physics, chemistry, biology, chronology and mathematics to build a quantitative understanding of how the Earth system works, and how it evolved to its current state."
I was trained as a meteorologist in China, not by my own "three wishes" but by the government's. I was then trained as a physical oceanographer in the States; this time by my own choice, because I wanted a Ph.D. degree that I could not get in China in the mid 1980s. I certainly have the advantage of being trained in both Met and PO. Some of my colleagues majored in physics and mathematics first, and they are like fish in the water, or shark in the sea