摘要： The initial phase of a major geomagnetic storm on 14 December 2006 was selected in order to investigate the ionizing effect of energetic electrons in the ionosphere. The global network of GPS receivers was used to analyze the total electron content (TEC). A strong positive ionospheric storm of ~20 TEC units (TECU) with ~6 h duration was observed on the dayside during the interval of northward interplanetary magnetic field. At the same time, the NOAA/POES satellites observed long‐lasting intense fluxes of >30 keV electrons in the topside ionosphere at middle and low latitudes, including a near‐equatorial forbidden zone outside of the South Atlantic Anomaly (SAA). We found that the TEC increases overlapped well with the enhancements of energetic electrons. Modeling of the ionospheric response by using a Global Self‐consistent Model of the Thermosphere, Ionosphere, and Protonosphere, based on the standard mechanisms of plasma transport, could only partially explain the ionospheric response and was unable to predict the long‐duration increase of TEC. For the energetic electrons, we estimated the ionizing effect of ~45 TECU and ~23 TECU in the topside ionosphere, respectively, inside and outside of SAA. The ionizing effect contributed from 50% to 100% of TEC increases and provided the long duration and wide latitudinal extension of the positive ionospheric storm. This finding is a very important argument in supporting significant ionizing effect of energetic electrons in the storm time ionosphere both at middle and low latitudes. Key Points TEC increases in the low‐ and middle‐latitude ionosphere at the initial storm phase Greater than 30 keV electron fluxes enhance significantly at the initial storm phase Energetic electron enhancements produce significant ionizing effect in the ionosphere 出版者： Washington: Blackwell Publishing Ltd 出版日期： 2016-06 出處： Journal of geophysical research : Space physics (2013 - Present), 2016-06, Vol.121 (6), p.5880-5896 資源來源： Wiley Online Library journals 版權： 2016. American Geophysical Union. All Rights Reserved. 識別號： ISSN: 2169-9380 識別號： ISSN: 2169-9402 識別號： EISSN: 2169-9402 識別號： DOI: 10.1002/2016JA022622
