Rossby radius of deformation

In atmospheric dynamics and physical oceanography, the Rossby radius of deformation is the length scale at which rotational effects become as important as buoyancy or gravity wave effects in the evolution of the flow about some disturbance.

For a barotropic ocean: ${\displaystyle L_{R}\equiv {\frac {(gD)^{1/2}}{f}}}$, where ${\displaystyle \,g}$ is the gravitational acceleration, ${\displaystyle \,D}$ is the water depth, and ${\displaystyle \,f}$ is the Coriolis parameter.

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