ASR Advances in Science and Research ASR Adv. Sci. Res. 1992-0636 Copernicus Publications Göttingen, Germany 10.5194/asr-4-77-2010 Tornado-type stationary vortex with nonlinear term due to moisture transport Rutkevich P. B. 1 Rutkevych P. P. 2 Space Research Institute (IKI), RAS, Moscow, Russia Institute of High Performance Computing, A*STAR, Singapore 14 06 2010 4 1 77 82 Copyright: © 2010 P. B. Rutkevich 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://asr.copernicus.org/articles/4/77/2010/asr-4-77-2010.html The full text article is available as a PDF file from https://asr.copernicus.org/articles/4/77/2010/asr-4-77-2010.pdf

Tornado vortex is believed to be essentially nonlinear phenomenon; and the puzzle to choose the nonlinear term(s) responsible for its formation is still unresolved. In the present work we consider the nonlinear term associated with atmosphere humidity, by introducing variable temperature gradient depending on the vertical velocity of the fluid. Such term is able to yield energy to the system and is very suitable for such a problem. Other nonlinear terms are neglected, assuming slow rotation, or in other words a "weak" tornado approximation. We consider one-dimensional radial boundary problem, and use a modificaiton of shooting method to satisfy boundary conditions at large radii. Obtained numerical solutions of the nonlinear differential equation qualitatively agree with the observed atmosphere vortices (tornados, tropical cyclones). The obtained results show general possibility of existence of unstable motion even in convectively stable atmosphere stratification.

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