Characteristics of CIR-driven storm induced traveling ionospheric disturbances over mid-latitude Europe from ionosonde and LOFAR data (SUNDIAL)

Magnetic storms are known to effectively generate atmospheric waves, result in negative effects on the space-based assets and require further thorough investigations. The goal of the proposed project was to search a relationship between auroral activity enhancement, initiated by corotating interaction region / high speed stream (CIR / HSS)-driven events and characteristics of traveling ionospheric disturbances (TIDs) observed over mid-latitude Europe. We thoroughly analysed both large-scale and medium-scale TID activity during CIR / HSS-driven magnetic storm on March 30 – April 6, 2023. Thanks to the PITHIA-NRF project and the valuable support provided by the TNA program, we successfully combined the efforts of scientists from the Institute of Atmospheric Physics CAS (Czech Republic) and the Space Research Centre PAS (Poland) to jointly detect and characterize TIDs using ionosonde, GNSS, and LOFAR scintillation techniques. A unified methodology was applied and further improved for data analysis, incorporating cross-correlation, spectral analysis, and bandpass filtering to ensure consistency across the obtained results. We detected the several time intervals with TIDs propagated from the high latitudes towards the equator associated with an enhancement in auroral activity. Ionosonde and GNSS based results show the consistency in estimation of TID characteristics. The detected large scale TIDs have the dominant periods of 50 – 80 min, horizontal phase velocities of 400 – 600 m/s and horizontal wavelengths of 1300 – 3500 km. In addition, an analysis of the LOFAR scintillation data revealed the intensification of irregularities which is likely to be caused by medium and small scale TIDs. The southward propagated TIDs in the broad range were detected and characterized during the selected magnetic storm interval. Based on this case study, we spotted that the TIDs at mid-latitudes were usually observed several (1 – 4) hours after the enhancement in the auroral activity characterized by IMAGE IE indices. We continue to analyse other CIR / HSS driven events to establish the validity of such relationship.