Quasi-two-dimensional turbulence
S.D. Danilov a,
D. Gurarie b
a A M Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, Pyzhevskii per. 3, Moscow, 109017, Russian Federation
b Department of Mathematics, Case Western Reserve University, Cleveland, Ohio, USA
We review the results of numerical and experimental studies in quasi-two-dimensional (Q2D) turbulence. We demonstrate that theoretical energy spectra with slopes-5/3 and-3 (Kraichnan-Batchelor-Leith) can be observed only for a special set of external parameters. The bottom drag, beta effect, finite Rossby-Obukhov radius or vertical stratification, which distinguish geophysical Q2D turbulence from its purely 2D counterpart, determine the organization of a Q2D flow on a large scale. Since the spectral energy flux in 2D turbulence is directed upscale, the bottom friction takes on a special role. In the absence of bottom drag the energy condenses on the largest resolvable scale and flow equilibration is not attained.
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