Total Electron Content evolution during the 27 February 2014 storm over the Iberian Peninsula and Northern Africa

In this work Total Electron Content (TEC) during the moderate geomagnetic storm of 27 February 2014 over the Iberian Peninsula and Northern Africa is analysed. The data used are coming from GNSS derived TEC and ROTI from several receiver stations from Spain, Portugal and Morocco. Maps of TEC are developed to study its evolution before, during and some days after the main phase of the storm. This study shows that before the storm, i.e. during quiet geomagnetic conditions, a northern crest of the Equatorial Ionosphere Anomaly (EIA) is located in Western North Africa with low gradients and values of TEC. During the main period of the storm, this northern crest of the EIA is also located in the Western North Africa with larger gradients that affect the southern part of the Iberian Peninsula. These gradients are present both in latitude and longitude. They are observed exclusively over this region but not seen in the rest of Southern Europe. In addition, increased values of ROTI from GNSS stations located in Southern Spain are also found during the storm, but not observed northwards and eastwards of that region. Since the Iberian Peninsula is located in a mid-latitude area not expected to be influenced by the EIA, these findings seem to indicate that the Southern part of the Peninsula could be influenced by the EIA during disturbed geomagnetic conditions.