%0 Journal Article
%T Extreme changes in the dayside ionosphere during a Carrington-type magnetic storm
%A Tsurutani Bruce T.
%A Verkhoglyadova Olga P.
%A Mannucci Anthony J.
%A Lakhina Gurbax S.
%J Journal of Space Weather and Space Climate
%D 2012
%I EDP Sciences
%R 10.1051/swsc/2012004
%X It is shown that during the 30 October 2003 superstorm, dayside O+ ions were uplifted to DMSP altitudes (~850 km). Peak densities were ~9 ¡Á 105 cm 3 during the magnetic storm main phase (peak Dst =  390 nT). By comparison the 1¨C2 September 1859 Carrington magnetic storm (peak Dst estimated at  1760 nT) was considerably stronger. We investigate the impact of this storm on the low- to mid-latitude ionosphere using a modified version of the NRL SAMI2 ionospheric code. It is found that the equatorial region (LAT = 0¡ã ¡À 15¡ã) is swept free of plasma within 15 min (or less) of storm onset. The plasma is swept to higher altitudes and higher latitudes due to E ¡Á B convection associated with the prompt penetration electric field. Equatorial Ionization Anomaly (EIA) O+ density enhancements are found to be located within the broad range of latitudes ~ ¡À (25¡ã¨C40¡ã) at ~500¨C900 km altitudes. Densities within these peaks are ~6 ¡Á 106 oxygen ions-cm 3 at ~700 km altitude, approximately +600% quiet time values. The oxygen ions at the top portions (850¨C1000 km) of uplifted EIAs will cause strong low-altitude satellite drag. Calculations are currently being performed on possible uplift of oxygen neutrals by ion-neutral coupling to understand if there might be further significant satellite drag forces present.
%K ionosphere (equatorial)
%K ionosphere (mid latitude)
%K electric field
%K coronal mass ejection (CME)
%K flares
%U http://dx.doi.org/10.1051/swsc/2012004