Table of Contents
ISRN Geophysics
Volume 2013 (2013), Article ID 215362, 12 pages
http://dx.doi.org/10.1155/2013/215362
Research Article

A Simulation Study of the Formation of Large-Scale Cyclonic and Anticyclonic Vortices in the Vicinity of the Intertropical Convergence Zone

1Polar Geophysical Institute, Kola Scientific Center of the Russian Academy of Sciences, Murmansk Region, Apatity 184209, Russia
2Space Research Institute of the Russian Academy of Sciences, Moscow 117997, Russia
3Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences, Moscow 125047, Russia

Received 31 January 2013; Accepted 26 February 2013

Academic Editors: A. De Santis, M. Ernesto, and A. Streltsov

Copyright © 2013 Igor V. Mingalev et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A regional nonhydrostatic mathematical model of the wind system of the lower atmosphere, developed recently in the Polar Geophysical Institute, is utilized to investigate the initial stage of the origin of large-scale vortices at tropical latitudes. The model produces three-dimensional distributions of the atmospheric parameters in the height range from 0 to 15 km over a limited region of the Earth’s surface. Time-dependent modeling is performed for the cases when, at the initial moment, the simulation domain is intersected by the intertropical convergence zone (ITCZ). Calculations are made for various cases in which the initial forms of the intertropical convergence zone are different and contained convexities with distinct shapes, which are consistent with the results of satellite microwave monitoring of the Earth’s atmosphere. The results of modeling indicate that the origin of convexities in the form of the intertropical convergence zone, having distinct configurations, can lead to the formation of different large-scale vortices, in particular, a cyclonic vortex, a pair of cyclonic-anticyclonic vortices, and a pair of cyclonic vortices, during a period not longer than three days. The radii of these large-scale vortices are about 400–600 km. The horizontal wind velocity in these vortices can achieve values of 15–20 m/s in the course of time.