Magnetic storm associated delayed sporadic E enhancements in the Brazilian Geomagnetic Anomaly

Journal Article · Sat Oct 01 04:00:00 EDT 1977 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA082i029p04777· OSTI ID:7287671

Batista, I S; Abdu, M A

Sporadic E layer behavior over Cachoeira Paulista (11/sup 0/57'S, 22/sup 0/32'E geomagnetic coordinates), located near the center of the Brazilian Geomagnetic Anomaly, is investigated during magnetically disturbed periods. Significant enhancements in the E/sub s/ layer parameters, f/sub t/E/sub s/ and f/sub b/E/sub s/ take place for short periods 2--3 hours) following a magnetic disturbance of moderate intensity. The enhancements, however, are delayed by 1--3 days with respect to the initiation of a disturbance. The electron density enhancement in the E/sub s/ layer inferred from f/sub b/E/sub s/ during such events are at times an order of magnitude larger than undisturbed values. Also, during some night events the ambient E region electron densities appear comparable to the regular daytime maximum values. The E/sub s/ traces in the ionograms during these events exhibit range spread in the echoes resembling the a-type E/sub s/, know to occur over auroral latitudes under disturbed conditions. These results are interpreted as evidence of enhanced charged particle precipitation in the E region over the geomagnetic anomaly following magnetic disturbances. The results also provide evidence that the E region response over our station is delayed with respect to magnetic activity.

• Research Organization: Instituto de Pesquisas Espaciais, Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), CP 515, Sao Jose dos Campos, SP, Brazil
• OSTI ID: 7287671
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 82:29; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BRAZIL
CHARGED-PARTICLE PRECIPITATION
E REGION
EARTH ATMOSPHERE
ELECTRON DENSITY
GEOMAGNETIC FIELD
IONOSPHERE
MAGNETIC FIELDS
MAGNETIC STORMS
SOUTH AMERICA
SPORADIC E