Models of the ocean circulation, and of the Earth’s climate, involve numerical solutions to the dynamical equations for momentum, heat and energy. Due to the computational complexity of this task, these equations are typically limited to describing only a subset of the full problem. In particular, temporal resolution is often limited to time-scales longer than about a day, and spatial-scales of about 10 km. Processes occurring on shorter time or spatial scales, such as internals waves, tidal processes, or turbulent mixing, must be incorporated into these models using a method of representation known as parameterization. The unresolved processes are represented by formulas involving parameters that govern the resolved flow. These formulas are derived using results from measurement, theory, and modeling.