research
Time intermittency and spectral features of the geomagnetic field
- Publication date
- Publisher
- INGV
Abstract
In the field of geomagnetism a number of studies have been devoted to the investigation of turbulence and intermittency
in the outer core fluid motions. Here, in order to obtain information on such phenomena we study
the time spectral and self-similarity features of the main geomagnetic field fluctuations as measured on the
Earth’s surface. The existence of a power law spectrum, characterised by an exponent a˜-11/3, and an anomalous
scaling of q-th order structure functions on time scales longer than 5 years, suggests the occurrence of intermittent
turbulence rather than classical Kolmogorov turbulence in the fluid core motions. These results are
briefly discussed in connection with the existence of a strong magnetic field and drift-wave turbulence