Spread F plasma bubble vertical rise velocities determined from spaced ionosonde observations

Journal Article · Tue Nov 01 04:00:00 EST 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA11p09197· OSTI ID:5015689

Abdu, M A; de Medeiros, R T; Sobral, J H.A.; Bittencourt, J A

Systematic time differences in the onsets of spread F events in the ionograms are observed between the magnetic equatorial station Fortaleza (4/sup 0/S, 38/sup 0/W, dip latitude 1.8/sup 0/S) and the low-latitude station Cachoeira Paulista (23/sup 0/S, 45/sup 0/W, dip latitude 14/sup 0/S), two stations in Brazil, located at close-by magnetic meridional planes (actually some 12/sup 0/ of magnetic longitude apart). On the assumption, justified from different experimental observations, that the spread F irregularities occur in strongly field-aligned plasma bubbles that extend several degrees on either side of the magnetic equator, and rise up in vertically elongated columns over the magnteic equator, we have related the observed time differences in the onsets of spread F events at the two stations to the plasma bubble vertical rise velocities of the plasma bubbles so determined are found to be well within the values measured by VHF radar and satellite techniques, and further show, at times, good correlations with the amplitude of the prereversal peak in the vertical drift velocities and the heights of the evening equatorial F layer. Possible implications of these results are discussed.

• Research Organization: Instituto de Pesquisas Espaciais, Conselho Nacional de Desenvolvimento Cientifico e Tecnologico
• OSTI ID: 5015689
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88:A11; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DISTURBANCES
EARTH ATMOSPHERE
F REGION
GEOMAGNETIC EQUATOR
INSTABILITY
IONOSPHERE
IONOSPHERIC STORMS
PLANETARY IONOSPHERES
PLASMA DENSITY
PLASMA DRIFT
PLASMA INSTABILITY
SPREAD F
TRAVELLING IONOSPHERIC DISTURBANCE