Improving the vertical electron density profile in ionospheric imaging at storm time: A case study on 25-27 September 2011

Ionospheric responses to geomagnetic storms are important because they can seriously affect radio propagation up to several GHz in frequency, resulting in deterioration of the system performance. There is a key difficulty in the representation of the vertical electron density profile during storms because many tomographic imaging techniques rely on statistical estimations of the profile, which are inadequate in extreme events. The approach here is to use radio occultation observations from Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) to provide this missing information. The method is evaluated over Europe and the United States for a major storm on 25-27 September 2011. The use of COSMIC profiles in GPS tomography does help to improve the vertical imaging accuracy of inversions during storm periods when compared to ionosonde and incoherent scatter radar observations. It is interesting to note that COSMIC vertical profiles are also able to facilitate better representation of the E layer. More availability of density profiles from COSMIC or other similar radio occultation satellites would be greatly welcomed in the future. Key Points COSMIC EDPs are used to improve the vertical distribution in ionospheric imagingResults compare better with independent data when COSMIC profiles are usedThe approach is able to facilitate E layer imaging