Abstract

Statistical properties of the auroral absorption fluctuations measured by the broad-beam riometer deployed at the South Pole Station were studied for different magnetic local times (MLT). The local intermittency measure technique based on the wavelet transform of the auroral absorption time series was used. It was shown that the flatness factor of the wavelet coefficients distribution generally lies outside the Gaussian statistics indicating the presence of intermittency. It was found that the auroral absorption is more intermittent in small scales and that the level of intermittency is strongly dependent on the MLT. The auroral absorption fluctuations are more intermittent in the night sector of MLT with the maximum between 20 and 24 h. The results obtained showed that the acceleration of precipitating particles is intermittent, especially near the substorm eye, where the level of turbulence is increased. © 2006.