Topside Electron Density profiles: Some comparisons between observations and models

M. MOSERT

Miramare, Trieste

Workshop; Workshop on Science Applications of GNSS in Developing Contries, followed by the: Seminar on Development and Use of the Ionospheric NeQuick Model; 2012

ICTP

The topside modeling involves two major aspects: The vertical scale height (H) and the profile functions to define profile shape Different techniques have been developed for calculating the vertical scale height(a) Calculating H from GPS derived TEC (Jakowski et al., 2002; Stankov et al., 2003), (b) Obtaining the Chapman H from ground-based ionosonde measurements (Huang and Reinisch, 2001, 2007), (c) Calculating H from topside sounder data. Depuev and Pulinets (2004) used data from the Intercosmos 19 satellite and (The IRI-2001 (Bilitza, 2001) topside formulation is based on the approach to model the profile using different sections with nearly constant gradients. The analytical representation of the profile as a function of the height is an exponential layer modulated by the Booker function, which is suitable the topside to a few kilometers above the peak, overestimating the upper part of the topside profile.Many efforts have been done to provide effective solutions(Coisson et al., 2002; Depuev and Pulinets, 2004, Bilitza,2004; Coisson and Radicella, 2005, among others).The new IRI 2007 version includes two new options for the topside electron density profile in addition to the old option (IRI-2001).d) NeQuick computed “H” varying with height based on empirical parameters(k parameter) The cases presented in this analysis indicate that the two IRI new options for the topside electron density formulation (Nequick and IRI-2001 corr) reproduce better the observations than the old IRI-2001 description. These results are in agreement with those presented by others researchers.