Articles | Volume 22, issue 7
Ann. Geophys., 22, 2431–2440, 2004
https://doi.org/10.5194/angeo-22-2431-2004

Special issue: Spatio-temporal analysis and multipoint measurements in space...

Ann. Geophys., 22, 2431–2440, 2004
https://doi.org/10.5194/angeo-22-2431-2004

  14 Jul 2004

14 Jul 2004

Multifractal structure of turbulence in the magnetospheric cusp

E. Yordanova1,2, M. Grzesiak1, A. W. Wernik1, B. Popielawska1, and K. Stasiewicz3 E. Yordanova et al.
  • 1Space Research Center, Polish Academy of Sciences, Poland
  • 2Space Research Institute, Bulgarian Academy of Science, Bulgaria
  • 3Swedish Institute of Space Physics, Uppsala, Swedennce, Bulgaria

Abstract. Magnetospheric cusps are regions which are characterized by highly turbulent plasma. We have used Polar magnetic field data to study the structure of turbulence in the cusp region. The wavelet transform modulus maxima method (WTMM) has been applied to estimate the scaling exponent of the partition function and singularity spectra. Their features are similar to those found in the nonlinear multifractal systems. We have found that the scaling exponent does not allow one to conclude which intermittency model fits the experiment better. However, the singularity spectra reveal that different models can be ascribed to turbulence observed under various IMF conditions. For northward IMF conditions the turbulence is consistent with the multifractal p-model of fully developed fluid turbulence. For southward IMF experimental data agree with the model of non-fully developed Kolmogorov-like fluid turbulence.