Global Ionospheric Response to a Periodic Sequence of HSS/CIR Events During the 2007–2008 Solar Minimum

In this study, we investigate the global ionospheric impact of high-speed solar wind streams/corotating interaction regions (HSS/CIR). A series ten such events are identified between December 1st 2007 and April 29th 2008, characterized in frequency domain by main spectral peaks corresponding to 27, 13.5, 9 6.75 days. The spectra magnetic field, speed proton density, as well those geomagnetic indices AE SYM-H solely dominated these features. By contrast, NmF2 a lesser extent hmF2 have much more complex structure, with secondary adding or replacing ones. We argue that is evidence nonlinear nature magnetosphere-ionosphere coupling, highlighted particularly response. Additionally, show closely correlated than all parameters describing activity. Finally, response shows higher correlation Bz any other parameter, AE, indicating for low-frequency part spectrum, high-latitude Joule heating particle precipitation play role prompt penetration electric fields dictating activity, case sequence HSS/CIR events.