Variation of the electron density in the high-latitude topside ionosphere during large magnetic storms

We investigate the response of the high-latitude topside ionosphere to large geomagnetic storms. For our study we employ electron-density profiles, derived from the Alouette and ISIS topside sounder satellites, available from http://nssdc.gsfc.nasa.gov/space/isis/isis-status.html which also describes a recent data restoration project that will enable this work to be expanded [1,2]. The focus is on the 20-yr interval from 1965 to 1985 when both solar-wind and Alouette/ISIS topside-sounder data are potentially available. Several case studies were investigated and some showed significant Ne enhancements in the high-latitude topside ionosphere. One of these cases is shown in detail in Figure 1.