Accession Number : ADP006270

Title :   The Trough in the Daytime F Layer: A Macroscopic Effect of Ionospheric-Magnetospheric Convection,

Corporate Author : GEOPHYSICS LAB (AFSC) HANSCOM AFB MA

Personal Author(s) : Whalen, J. A.

Report Date : 03 MAY 1990

Pagination or Media Count : 9

Abstract : The daytime F layer through is a major result of ionospheric-magnetospheric convection, appearing in the winter high latitude ionosphere as a continuous band thousands of kilometers in extent in which the daytime F layer electron density is depleted, often by an order of magnitude. As observed by a global array of ionospheric sounders during solar maximum, the trough occurs in regions of sunward convection, in the morning corresponding to the dawn cell and in the afternoon corresponding to the dusk cell. The formation of the trough is consistent with the transport of low density nighttime plasma into the day sector where it displaces high density daytime plasma, although other mechanisms such as ion chemical effects may also play a role.

Descriptors :   *IONOSPHERIC DISTURBANCES, ELECTRON DENSITY, WINTER, F REGION, HIGH LATITUDES, DIURNAL VARIATIONS, MAGNETOSPHERE, CONVECTION(ATMOSPHERIC).

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE