Modeling scintillation produced by ionospheric Kelvin Helmholtz in the cusp ionosphere using GEMINI-SIGMA

Ionospheric irregularities are known to cause fluctuations in radio signals called scintillation in the phase and amplitude of the complex signal. The turbulent structures responsible for the scintillation are a few hundreds of meters to few tens of kilometers scale sizes (intermediate scale sizes). With the growing interest in high latitude scintillation, we would like to investigate the effect of typical physical mechanisms on the radio scintillation.

Here we present our modeling studies of Global Positioning System (GPS) scintillation through Kelvin Helmholtz instability (KHI) in the cusp region. For modeling we use the first principles based Geospace Environment Model of Ion-Neutral Interactions (GEMINI) and Satellite-beacon Ionospheric-scintillation Global Model of the upper Atmosphere (SIGMA). We utilize a cusp event study with detailed observations from the EISCAT Svalbard Radar (ESR) and scintillations detected from a network of four Global Navigation Satellite Systems (GNSS) receivers in Svalbard. The event presents evidences of the role of magnetosphere-ionosphere coupling in the generation of plasma irregularities and scintillations in the cusp. Using numerical simulations, we investigate the potential role of the Kelvin-Helmholtz instability in producing such scintillation. Furthermore, we compare the results with characteristics of GPS scintillations associated with a polar cap patch and the gradient drift instability to deduce distinctive characteristics of the respective plasma irregularities.