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An analysis of positive ionospheric storms was performed in the dayside region of the equatorial ionization anomaly on the declining phase of solar activity in 2004 to 2008. We revealed so-called recurrent ionospheric storms (RIS) consisted in an increase of total electron content (TEC) during recurrent geomagnetic storms (RGS). RISs peaked 3 to 4 days after the RGS onset, i.e. on the recovery phase, during high-intensity long-duration continuous auroral activity produced by high-speed solar wind streams. The response of RISs to solar, heliospheric and geomagnetic drivers revealed a prominent longitudinal variation. Most intense RISs in response to heliospheric and geomagnetic drivers were found in the longitudinal ranges from 90° to 180° and from –180° to –120°. The highest correlations for RISs exhibit a prominent annual asymmetry with maximum during the winter season. An analysis of electron content vertical profiles, derived from two independent methods using ionosondes and COSMIC/FORMOSAT-3 radio occultation, shows that in the maximum of RIS, the F2 layer is thickening, NmF2 increases by ~50% and hmF2 elevates by a few tens of kilometers. The thermosphere and magnetosphere are considered as sources in generation of RISs.