Downwelling is the downward movement of a fluid parcel and its properties (e.g., salinity, temperature, pH) within a larger fluid. It is closely related to upwelling, the upward movement of fluid.

While downwelling is most commonly used to describe an oceanic process, it's also used to describe a variety of Earth phenomena. This includes mantle dynamics, air movement, and movement in freshwater systems (e.g., large lakes). This article will focus on oceanic downwelling