Middle- and low-latitude ionosphere response to 2015 St. Patrick\textquoterights Day geomagnetic storm

Abstract
<p>This paper presents a study of the St Patrick\textquoterights Day storm of 2015, with its ionospheric response at middle and low latitudes. The effects of the storm in each longitudinal sector (Asian, African, American, and Pacific) are characterized using global and regional electron content. At the beginning of the storm, one or two ionospheric positive storm effects are observed depending on the longitudinal zones. After the main phase of the storm, a strong decrease in ionization is observed at all longitudes, lasting several days. The American region exhibits the most remarkable increase in vertical total electron content (vTEC), while in the Asian sector, the largest decrease in vTEC is observed. At low latitudes, using spectral analysis, we were able to separate the effects of the prompt penetration of the magnetospheric convection electric field (PPEF) and of the disturbance dynamo electric field (DDEF) on the basis of ground magnetic data. Concerning the PPEF, Earth\textquoterights magnetic field oscillations occur simultaneously in the Asian, African, and American sectors, during southward magnetization of the <em>B<sub>z</sub></em> component of the interplanetary magnetic field. Concerning the DDEF, diurnal magnetic oscillations in the horizontal component H of the Earth\textquoterights magnetic field exhibit a behavior that is opposed to the regular one. These diurnal oscillations are recognized to last several days in all longitudinal sectors. The observational data obtained by all sensors used in the present paper can be interpreted on the basis of existing theoretical models.</p>
Year of Publication
2016
Journal
Journal of Geophysical Research: Space Physics
Volume
121
Number of Pages
3421-3438
Date Published
03/2016
URL
http://doi.wiley.com/10.1002/2015JA022299
DOI
10.1002/2015JA022299