Accession Number : AD0719876

Title :   Ionospheric Winds in the Auroral Zone,

Corporate Author : UNIVERSITY COLL LONDON (ENGLAND) DEPT OF PHYSICS

Personal Author(s) : Rees,David

Report Date : OCT 1970

Pagination or Media Count : 26

Abstract : Observations of the drift velocity of rocket-borne chemical releases have been used to determine neutral wind velocity and ion velocity in the altitude range 90-230 km at ESRANGE, Kiruna. The ion cloud drift measurements have demonstrated the orthogonality of the simultaneous magnetic perturbation vector at ground level and the ion drift vector in the F region of the ionosphere. This result implies that in the auroral zone Hall currents are predominantly responsible for that part of the total magnetic perturbation seen at ground level due to ionospheric currents. A comparison of neutral wind velocity profiles obtained under quiet and disturbed geomagnetic conditions has shown that in the auroral zone the observed west-east neutral wind component above about 120 km altitude is directly correlated with the mean south-north magnetic perturbation vector over a period of two-three hours prior to the observations. This correlation is due to acceleration of the neutral atmosphere above 120 km by ions drifting in a meridional electric field. Both the ground magnetic perturbation and the neutral acceleration are direct functions of the locally magnetic perturbation and the neutral acceleration are direct functions of the locally enhanced electric field and of the electron (and hence ion) density. (Author)

Descriptors :   (*IONOSPHERE, WIND), (*IONOSPHERIC DISTURBANCES, MAGNETIC STORMS), DRIFT, CORRELATION TECHNIQUES, MAGNETOMETERS, ATMOSPHERIC MOTION, VELOCITY, TRACER STUDIES, GREAT BRITAIN

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE