Inferred Ionospheric irregularity scales from amplitude scintillation

The analysis of the structure function of a GNSS signal amplitude measured on the ground has revealed that ionospheric scintillation could be considered a proxy for ionospheric turbulence. More precisely, and in a recent report, the existence of a linear range with respect to the time lag in the structure function has been highlighted. In this context, the inertial-range analog has been determined from the analysis of a large set of scintillation events collected over several days from Pond Inlet located in the northern polar region and from Sao Paolo located at 23.2 degrees South of the Equator. At high latitude, we found that the mean value of the first-order scaling exponent is H = 0.55 ± 0.07, while a low altitude H is typically larger with H = 0.84 ±.11. This result clearly indicates that the long-time lag positive correlation remains persistent in the low latitude region. At high latitude however, both negative and positive long time lag correlation can occur. In addition, the obtained results clearly show that the inertial range analog is significantly smaller at high latitude, particularly the upper bound time lags at which the structure function deviates from linearity. This distinction may pinpoint to a difference in the ionospheric irregularity drift speed.