Brunt-Väisälä frequency

In atmospheric dynamics and oceanography, the Brunt-Väisälä frequency, or buoyancy frequency, is the frequency at which a vertically displaced parcel will oscillate within a statically stable environment. In the atmosphere,

$N \equiv \sqrt{\frac{g}{\theta}\frac{d\theta}{dz}}$ , where

θ

is potential temperature,

g

is the local acceleration of gravity, and

z

is geometric height.