Introduction 1/2

1. Assimilation of autoscaled data and regional and local ionospheric models as input source for a real-time 3-D IRI modeling: additional and planned tests M. Pezzopane a, M. Pietrella a, A. Pignatelli a, A. Settimi a, C. Scotto a, B. Zolesi a, C. Bianchi a, Lj. R. Cander b a Istituto Nazionale di Geofisica e Vulcanologia b Rutherford Appleton Laboratory, Chilton, OX11 0QX, UK michael.pezzopane@ingv.it

2. Introduction 1/2 Ionospheric models are important for providing a comprehensive specification of the three-dimensional (3-D) electron density of the ionosphere; the International Reference Ionosphere is the de facto international standard for the climatological specification of ionospheric parameters; although global models of the F2 layer critical frequency foF2 and propagation factor M(3000)F2, such as those of the CCIR and the URSI, represent a valid input source for a 3-D modeling of the ionosphere, regional and local models of these ionospheric characteristics can be important to catch some features that may be easily neglected in global models; moreover, in the light of a real-time modeling of the ionosphere, in the last decades we have appreciated the valuable data source represented by the modern real-time ionosonde observations.

3. Introduction 2/2 real-time autoscaled foF2 and M(3000)F2 data and real-time electron density profiles local/regional nowcasting maps of foF2 and M(3000)F2 real-time 3-D electron density modeling [Pezzopane et al., Radio Sci., 2011]

4. Input sources of the model 1/2 Autoscaling of vertical soundings ARTIST [Huang and Reinisch, Radio Sci., 1983; Galkin and Reinisch, INAG bulletin, 2008] [Pezzopane and Scotto, Radio Sci., 2007] Autoscala

5. Input sources of the model 2/2 SIRMUP procedure [Zolesi et al., Radio Sci., 2004; Tsagouri et al., JASTP, 2005] is based on the idea that real-time values of foF2 and M(3000)F2 at one location can be determined from the climatological SIRM model [Zolesi et al., Radio Sci.,1996] by using an effective sunspot number (Reff) based on real-time ionosonde observations instead of the smoothed sunspot number R12. The method of determining Reff was introduced by Houminer et al. [JEEE, 1993]. Reff is chosen to give the best fit between the SIRM model calculation and real measurements obtained from a grid of ionosondes located in the mapping area. The SIRMUP has the capability to generate the real-time updated foF2 and M(3000)F2 values on a user-specified spatial grid.

6. Description of the model

7. Assimilation process of the measured electron density profiles 1/2

8. Assimilation process of the measured electron density profiles 2/2

9. Validation results 1/4

10. Validation results 2/4 quasi-stationary conditions around noon

11. Validation results 3/4 solar terminator conditions around sunrise

12. Validation results 4/4

13. Additional tests 1/5

14. positive phase negative phase Additional tests 2/5

15. positive phase negative phase Additional tests 3/5

16. Additional tests 4/5 disturbed conditions – positive ionospheric phase

17. Additional tests 5/5 disturbed conditions – negative ionospheric phase

18. Further planned tests 1/4 1) Testing the model on additional disturbed periods;

19. Further planned tests 2/4 1) Testing the model on additional disturbed periods; 2) using more than two reference ionospheric stations;

20. Further planned tests 3/4 1) Testing the model on additional disturbed periods; 2) using more than two reference ionospheric stations; 3) use of a ray tracing technique to synthesize oblique ionograms on the basis of the IRI-SIRMUP-P 3D electron density matrix. The MUFs of these synthetic ionograms will be then compared with the MUFs of recorded oblique ionograms;

21. Further planned tests 4/4 1) Testing the model on additional disturbed periods; 2) using more than two reference ionospheric stations; 3) use of a ray tracing technique to synthesize oblique ionograms on the basis of the IRI-SIRMUP-P 3D electron density matrix. The MUFs of these synthetic ionograms will be then compared with the MUFs of recorded oblique ionograms; 4) use of other foF2/M(3000)F2 regional models in order to test the 3-D model at different regions.

22. Thank you