1. On the Use of Modified Taylor Diagrams to Compare Ionospheric Models Sean Elvidge, Matthew Angling November 20 th, 2014

2. MODIFIED TAYLOR DIAGRAMS Construction of

3. 3 A

4. 4 Pearson’s r correlation (R) A

5. 5 A

6. 6 A Models should ‘aim’ to be next to Observed marker

7. 7 A

8. 8 A

9. MODIFIED TAYLOR DIAGRAMS Example

10. 10 OBSABCD Std. Dev. 7.8600.7917.8758.29410.22 Corr. 1.0000.9670.2740.8670.995 Bias 0.0000.089-0.3930.7821.965 Error Std. Dev. 0.0007.0529.4824.1922.523 RMS 0.0007.0539.4904.2643.200

11. 11 OBSABCD Std. Dev. 7.8600.7917.8758.29410.22 Corr. 1.0000.9670.2740.8670.995 Bias 0.0000.089-0.3930.7821.965 Error Std. Dev. 0.0007.0529.4824.1922.523 RMS 0.0007.0539.4904.2643.200

12. MODEL COMPARISON Test Scenario

13. IRI-2007 is the 2007 version of the International Reference Ionosphere, the international standard. GITM is the Global Ionosphere Thermosphere Model from the University of Michigan, USA. TIE-GCM is the Thermosphere Ionosphere Electrodynamics General Circulation model from NCAR, Boulder, USA. EDAM is the Electron Density Assimilative Model from QinetiQ, UK. GPSII is the NorthWest Research Associates, USA model. mNeQuick is the data ingestion version of NeQuick, from ICTP and IGAM. Models

14. Tested over September 2011. Assimilated ionosonde data from Grahamstown in the Republic of South Africa (RSA). Assimilated GNSS data from mid Sub-Saharan Africa. Compared the models output to data from the other three ionosondes in RSA, Hermanus, Louisvale and Madimbo. Full results published in Radio Science. Just presenting the Hermanus results here. Image from ISES Regional Warning Centre for Africa. Test Scenario

15. MODEL COMPARISON Test Results

22. Conclusions Modified Taylor diagrams have been developed to extend Taylor diagrams to show:  Model bias,  Standard deviation of errors,  Mean square error. McNamara, L. F., M. J. Angling, S. Elvidge, S. V Fridman, M. A. Hausman, L. J. Nickisch, L.-A. A. McKinnell, and A. H. Hausman (2013), Assimilation procedures for updating ionospheric profiles below the F2 peak, Radio Sci., 48(2), 143–157, doi:10.1002/rds.20020. Elvidge, S., M. J. Angling, B. Nava, On the use of modified Taylor diagrams to compare ionospheric assimilation models, Radio Sci., 49, doi: 10.1002/2014RS005435. 22 / 24