Ca. Reddy et Hg. Mayr, STORM-TIME PENETRATION TO LOW LATITUDES OF MAGNETOSPHERIC-IONOSPHERICCONVECTION AND CONVECTION-DRIVEN THERMOSPHERIC WINDS, Geophysical research letters, 25(16), 1998, pp. 3075-3078
From DE-2 satellite measurements during two magnetic storms, we show t
hat (i) the magnetospheric convection-driven east-west ion flows of hi
gh velocities (1400 m/s) penetrate to magnetic latitudes as low as 30
degrees, with larger velocities (2000-3000 m/s) appearing at 45 degree
s 50 degrees latitudes, and (ii) high velocities (300-640 m/s) thermos
pheric winds appear in association with the : above ion flows. The sim
ilarity of the latitude structures and time evolutions of the ion and
neutral motions indicates that the zonal winds are driven by ma,magnet
ospheric-ionospheric convection through ion drag. These velocities of
the convection-driven ion flows and winds at such low latitudes are mu
ch larger than those reported from observations or predicted by curren
t models.