E-Field Effects on F-Region Winds at High Latitudes
Location
Yosemite National Park
Start Date
2-7-1974 10:00 AM
End Date
2-7-1974 10:00 AM
Description
During the last two years Doppler shift observations of the 6300A atomic oxygen line were carried out with the 15 cm Fabry-Perot interferometer, of the Michigan Airglow Observatory, located near College, Alaska (L = 5.6; A = 65°). These have provided comprehensive information on the nighttime behavior of thermospheric neutral winds. Supporting radar backscatter measurements of ionization drifts, and thus electric fields, present an excellent opportunity to establish the influence of E-fields on the neutral winds.. These observations have indicated that, in general, both the neutral wind and ionization drift are to the west, in the F-region, during the premidnight period. This westward ionization drift is consistent with the general magnetospheric convection pattern, but the neutral wind is in a direction opposite to the diurnal pressure gradients and thus must be controlled to a significant degree by ion drag. In the postmidnight period while the ionization drift turns east, following the magnetospheric convection pattern, the main component of the neutral wind is southward. The exact details of the driving forces for this meridional neutral wind are not yet well established, but they are certain to be due to a combination of pressure gradients caused by the diurnal and auroral heat sources, the coriolis force and ion drag.
E-Field Effects on F-Region Winds at High Latitudes
Yosemite National Park
During the last two years Doppler shift observations of the 6300A atomic oxygen line were carried out with the 15 cm Fabry-Perot interferometer, of the Michigan Airglow Observatory, located near College, Alaska (L = 5.6; A = 65°). These have provided comprehensive information on the nighttime behavior of thermospheric neutral winds. Supporting radar backscatter measurements of ionization drifts, and thus electric fields, present an excellent opportunity to establish the influence of E-fields on the neutral winds.. These observations have indicated that, in general, both the neutral wind and ionization drift are to the west, in the F-region, during the premidnight period. This westward ionization drift is consistent with the general magnetospheric convection pattern, but the neutral wind is in a direction opposite to the diurnal pressure gradients and thus must be controlled to a significant degree by ion drag. In the postmidnight period while the ionization drift turns east, following the magnetospheric convection pattern, the main component of the neutral wind is southward. The exact details of the driving forces for this meridional neutral wind are not yet well established, but they are certain to be due to a combination of pressure gradients caused by the diurnal and auroral heat sources, the coriolis force and ion drag.