STARILITY OF EQUATORIAL DISTURBANCES IN AN IDEALIZED DIPOLE MAGNETIC FIELD EMBEDDED IN A NONUNIFORM ATMOSPHERE

Abstract

The propagation of the small amplitude disturbances in an inhomogeneous atmosphere embedded in an idealized dipole field of a uniformly magnetized body in considered. The gravitational forces are included. It is found that due to inhomogeneity of either the density or magnetic intensity the disturbances generally tend to grow excepting in a special case. Tbis conforms to the general belief on the formation of blocks in atmosphere. But in the special case wben the local Alfven speed is constant and when the phase velocity lies between magneto, acoustic mode and magneto,acoustic mode modified by Lorentz force, the disturbances die Out.