Comparative study of VHF scintillation and spread F events over Natal and Fortaleza in Brazil
A comparative study is carried out of the equatorial ionospheric irregularity occurrences, as observed by range spread F events over Fortaleza (4/sup 0/S, 38/sup 0/W, dip latitude 1.8/sup 0/) and satellite VHF signal scientillation event over Natal (5.8/sup 0/S. 33.23/sup 0/W, dip latitude 4.8/sup 0/S) for a one-year period 1978. Close association is observed in the occurrences and the durations of the irregularities at the two stations. Marked differences in the seasonal behavior of the occurrences of the irregularity events over these two stations are noted with respect to that over Huancayo, most important of them being that while the latter station presents equinoctial maxima in the occurrence rates (as over some African stations), the Brazilian stations show an additional and pronounced peak in December. This result is explained as possible evidence of magnetic declination control of the spread F irregularity generation and its seasonal dependence. The present results have important implications also on the coexistence of different irregularity scale sizes during equatorial plasma bubble irregularity events.
- Research Organization:
- Instituto de Pesquisas Espaciais, Conselho Nacional de Desenvolvimento Cientifico e Tecnolgico, 12200 Sao Jose dos Campos, Sao Paulo, Brazil
- OSTI ID:
- 5667880
- Journal Information:
- J. Geophys. Res.; (United States), Vol. 88:A8
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
SPREAD F
PLASMA DENSITY
GEOMAGNETIC FIELD
IONOSPHERIC STORMS
SEASONAL VARIATIONS
TROPICAL REGIONS
EARTH ATMOSPHERE
F REGION
IONOSPHERE
MAGNETIC FIELDS
PLANETARY IONOSPHERES
VARIATIONS
640201* - Atmospheric Physics- Auroral
Ionospheric
& Magetospheric Phenomena