Global Ionospheric/Magnetospheric Response to the Bastille Day Storm

Gang Lu 1 (303-497-1554; ganglu@ucar.edu)
Arthur D Richmond 1 
Thomas J Immel 2 
Harald U Frey 2 
Frederick J Rich 3 
Marc R Hairston 4 
David S Evans 5 

1 NCAR/HAO, 3450 Mitchell Lane, Boulder, CO 80301, United States 
2 Space Physics Lab., University of California at Berkeley, Berkeley, CA 94720,
  United States 
3 Air Force Research Lab., 29 Randolph Rd, Hanscom AFB, MA 01731, United States 
4 University of Texas at Dallas, Center for Space Sciences, Richardson, TX 75083,
  United States 
5 NOAA/SEC, 325 Broadway, Boulder, CO 80303, United States 

The Bastille Day geomagnetic storm of 15-16 July 2000 was associated
with the strongly southward IMF condition. The storm had a maximum AE
value of 3700 nT and a minimum Dst value of -400 nT. Global
ionospheric/magnetospheric response to the Bastille Day storm is
analyzed using a comprehensive set of data collected from both space and
ground based instruments. In particular, we show the usage of global
auroral images obtained from the IMAGE satellite FUV instrument in the
AMIE data assimilation procedure. We examine quantitatively the
distribution and partitioning of auroral precipitation and Joule heating
during the storm. Amongst the most striking features in terms of
ionospheric response to the extremely southward IMF Bz are the
penetration of the ionospheric electric field and the apparent
saturation in the cross polar cap potential drop.