On the Origin of the Heliospheric Magnetic Field Polarity Inversion at High Latitudes

High latitude observations of the magnetic field by the Ulysses spacecraft have shown a significant number od cases where the radial magnetic field polarity is reversed with respect the dominant polarity of the coronal hole from which the wind emanates. Such reversals have the nature of folded back magnetic field lines. It has been suggested that such reversals are due to reconnection of closed and open field lines in the lower corona which would launch a large amplitude Alfvén wave into the solar wind. The kink in the field line however is unstable and disappears within a few dynamical time-scales. We suggest an alternative mechanism for the generation of the polarity reversal, namely, the coupling of standard large amplitude Alfvén turbulence in the low frequency regime propagating away from the sun with the microstream shears observed in the high speed solar wind. In this way reversals are generated naturally during propagation from the sun in a time scale consistent with their observation by Ulysses.