Articles | Volume 9, issue 3/4
https://doi.org/10.5194/npg-9-333-2002
https://doi.org/10.5194/npg-9-333-2002
31 Aug 2002
31 Aug 2002

Acoustic-gravity nonlinear structures

D. Jovanović, L. Stenflo, and P. K. Shukla

Abstract. A catalogue of nonlinear vortex structures associated with acoustic-gravity perturbations in the Earth's atmosphere is presented. Besides the previously known Kelvin-Stewart cat's eyes, dipolar and tripolar structures, new solutions having the form of a row of counter-rotating vortices, and several weakly two-dimensional vortex chains are given. The existence conditions for these nonlinear structures are discussed with respect to the presence of inhomogeneities of the shear flows. The mode-coupling mechanism for the nonlinear generation of shear flows in the presence of linearly unstable acoustic-gravity waves, possibly also leading to intermittency and chaos, is presented.