Physics of auroral phenomena : proceedings of the 33rd Annual seminar, Apatity, 02 - 05 March, 2010 / [ed.: A.G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2011. - 206 с. : ил.

The simulation results indicate that physical reason o f the formation of the calculated tropical cyclones is the origin of a convexity in the configuration of the intratropical convergence zone. As a rule, such convexities are observed during the periods of rebuilding o f the global circulation of the atmosphere. The origin of a convexity o f the intratropical convergence zone leads to beginning o f an instability o f air flow. As a consequence, a large-scale vortex flow arises in the lower atmosphere, with its center being close to the southern edge of the initial intratropical convergence zone. In the course of time, the horizontal wind velocity in the vortex flow increases due to a transformation o f energy, emitted owing to phase transitions of water vapor to micro drops of water and ice particles in the upward motion of air, into kinetic energy of the air flow. I. V. Mingalev at al. / / '/ ; / / / / / / / / ' '' ’ '■ * / - '' *' t «: <. f f ' ■ > :■/ /■/ «• ./ Щ:/ / / / . - / / ; / / / S 5 10 15 20 25 Longitude, deg 10 15 20 25 Longitude, deg Fig. 2. The same as in Fig. 1, but obtained for the second initial configuration of the intratropical convergence zone. Fig. 3. The same as in Fig. 1, but obtained for the third initial configuration o f the intratropical convergence zone. Conclusions To simulate the initial stage of the formation of cyclones at tropical latitudes o f the northern hemisphere, the regional mathematical model of the neutral wind system of lower atmosphere, developed recently, is applied. The simulation domain covers the altitude range from 0 to 15 km, its dimensions in longitudinal and latitudinal 184