Seasonal variation of the total electron content, maximum electron density and equivalent slab thickness at a South-American station

Ionospheric slab thickness at the equatorial anomaly region after the deep solar minimum of cycle 23/24

“…In the South American sector, the first study reporting the equivalent ionospheric slab thickness derived at the region of the equatorial ionization anomaly (EIA) is due to Mansilla et al (2005). Mansilla and co-authors investigated the seasonal behavior of the ionospheric slab thickness over the low-latitude station of Tucumán (26.9°S; 65.4°W), Argentina, during a period of high solar activity between April/1982 andMarch/1983.…”

Harmonic analysis of total electron contents time series: methodology and results

“…The well-known annual cycle results from the changing of the solar zenith angle and hence solar radiation, through one year. The first harmonics (183 days) known as semiannual signal is due to seasonal variation of F 2 region (Mansillaa et al 2005). Total F 2 ionization is actually lower in the local summer months than in the winter (Seeber 2003), which is known as the winter anomaly.…”

Diurnal variations of the total electron content under quiet helio-geomagnetic conditions

“…The diurnal minimum ($ 5 TECU) was registered at all stations between 05:00 and 06:00 LT (Ramo Rao et al, 2006;Bagiya et al, 2009). TEC behavior in undisturbed geomagnetic conditions, but high level of solar activity (1982)(1983), was discussed in Mansilla et al (2005). The authors of (Mansilla et al, 2005) applied data on TEC measured using signals from geostationary satellites and on F2 layer critical frequency f 0 F2 measured at the subequatorial station Tucuman in South America.…”