It is generally believed that sunspots are the emergent part of magnetic flux
tubes in the solar interior. These tubes are created at the base of the
convection zone and rise to the surface due to their magnetic buoyancy. The
motion of plasma in the convection zone being highly turbulent, the surface
manifestation of sunspots may retain the signature of this turbulence,
including its intermittency. From direct observations of sunspots, and indirect
observations of the concentration of cosmogenic isotopes 14C in tree rings
or 10Be in polar ice, power spectral densities in frequency are plotted.
Two different frequency scalings emerge, depending on whether the Sun is
quiescent or active. %magnetic activity is maximum or minimum. From direct
observations we can also calculate scaling exponents. These testify to a strong
intermittency, comparable with that observed in the solar wind.Comment: 5 pages, 6 figures, accepted for publication in MNRAS Letter