Oceanology
In oceanology, bottom water is by the ocean floor. It has characteristics are markedly distinct from the above layer in terms of oxygen content, salinity, bulk temperature (characteristic temperature), and hence density.
The Antarctic Bottom Water is the source of most bottom water in southern parts of Pacific Ocean, Indian Ocean and Atlantic Ocean, and even in parts of the North Atlantic. Bottom waters flow very slowly, driven mainly by slope topography and differences in temperature and salinity, especially compared to wind-driven surface ocean currents.
The bottom water of the Arctic Ocean is more isolated, due to the topography of the Arctic ocean floor and the surrounding Arctic shelves.
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