1. Ionospheric responses to the particular solar events Zbyšek Mošna 1,2, Petra Šauli 1, K. Georgieva 3 1- Institute of Atmospheric Physics ASCR, Prague, Czech Republic 2- Department of Surface and Plasma Science, Charles University, Prague, Czech Republic 3- Solar-Terrestrial Influences Laboratory, BAS, Bulgaria

2. Solar events Three events from year 2004 High Speed Solar Stream (HSS, Mar 09) Magnetic Cloud with rightward rotation of magnetic field (MC R, Feb 11) Magnetic Cloud with leftward rotation (MC L, Nov 07)

3. 2004 Mar. 09 – HSS Magnetic field Velocity of SW 911137 day 911137 day B By Bx Bz vy vx vz

4. 2004 Feb. 11 - Magnetic Cloud R 1213 1411 day B By Bx Bz vy vx vz 1213 1411 day Magnetic field Velocity of SW

5. 2004 Nov.07 - Magnetic Cloud L By Bx Bz vy vx vz 8910 7 day 8910 7 day Magnetic field Velocity of SW

6. Geomagnetic response in Dst The strongest response for MC L Similar values of Dst drop

7. Ionospheric vertical sounding (1) Quiet ionogram - Pruhonice observatory Mar. 11, 2004 200 400 800 600 (km) 1000 h’F2 2 46 8 (MHz) foF2 Plasma frequency profile F2 Analyzed data: h’F2, foF2, plasma frequency profile 9 days for each event (4 days before are reference,15 min resolution)

8. Ionospheric vertical sounding (2) Disturbed ionogram – Pruhonice observatory Feb. 12 2004 46 8 (MHz) 200 400 800 600 (km) 2 1000 Problems: splitting, spread, vanishing, blanketing…

9. Diurnal course of foF2 and h’F2 after HSS foF2 h’F2 2 4 6 8 10 MHz 4 106 8 12 14 day 200 400 km

10. Scalogram – time evolution of the plasma frequencies profiles after HSS 46 8 200 400 km 8 6 4 MHz Passing of Traveling Ionospheric Disturbance (TID)

11. Diurnal course of foF2 and h’F2 after MC R foF2 h’F2 10 16 8 12 14 day 6 4 MHz 2 8 200 400 km 10

12. Scalogram – time evolution of the plasma frequencies profiles after MC R 8 6 4 MHz 2 10 16 8 12 14 day Oscillations – wave-like structures remain several days – AGW with source in the midlatitudes

13. Diurnal course of foF2 and h’F2 after MC L foF2 h’F2 61048day1214 6 4 MHz 2 8 10 200 400 km

14. Scalogram – time evolution of the plasma frequencies profiles after MC L 8 6 4 MHz 2 61048day1214 200

15. Conclusion Similar and high response to the solar events for several days in case of HSS and MC L (although very different Dst) HSS, MC L: Decrease of foF2 and plasma frequencies in the height profile and increase in h’F2 Oscillations of h’F2 after passing the TID Wave-like structures with the source in midlatitudes MC R: No significant change in mean values of daily ionospheric parametres, decrease in night foF2, oscillations of the h’F2 and in plasma frequencies profile