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Variação sazonal da camada-E na região equatorial e de baixa latitude no setor brasileiro

2009; Volume: 8; Issue: 8 Linguagem: Inglês

10.5196/physicae.8.5

2236-3521

Artur Cristiano Arantes Filho, Y. Sahai,

GNSS positioning and interference

The objective of this work was to study the occurrence and seasonal variation of the sporadic-E (Es) layer observed at Palmas (PAL, 10.2 S, 48.2 W), close to the magnetic equator and Sao Jose dos Campos (SJC, 23.2 S, 45.9 W), localized in the region of the equatorial ionospheric anomaly. The data regarding the Es were obtained through digital ionosondes operating on a routine basis at PAL and SJC. The periods investigated were July 2003 (winter solstice), October 2003 (spring equinox), January 2004 (summer solstice) and April 2004 (autumn equinox). In the present study only data obtained on geomagnetically quiet days and interval of time between 18 L.T. to 06 L.T. (next day) were used. It should be mentioned that the occurrence of Es during daytime was very small. The seasonal variation studied indicates maximum presence of Es at both PAL and SJC during winter solstice month.