High-accuracy method for measuring profiles of buoyancy periods

We present a theoretical basis for a direct method of determining buoyancy period (frequency) as a function of depth by registering the displacements and oscillations of the hydrodynamic wake formed in a stationary liquid by freely ascending bubbles (the density marker method). We achieve an error no greater than 5% by comparing theoretical computations of parameters for internal waves generated by a free submerged thin wake having uniform transverse density distribution in an exponentially stratified liquid with measurements of internal waves in the liquid. We find that there is a power law for the decrease in amplitude of internal oscillations with time.