Heliospheric magnetic field polarity inversions at high heliographic latitudes

The heliospheric magnetic field over the poles of the sun has been examined to identify intervals when the polarity of the magnetic field deviates sig nificantly from the calculated Parker spiral, using Ulysses observations in 1994 and 1995, near solar minimum. Intervals with deviation > 90 degrees h ave been identified, corresponding to magnetic field vectors pointing in th e hemisphere opposite to that of the dominant polarity in the high speed so lar wind originating in the polar coronal holes. The number of inversion pe riods decreases as the averaging period is increased from 1 to 12 hours. Th eir distribution was found to vary in time over the northern solar pole, wh ere the average direction also deviated from the Parker direction. The prop agation direction of waves during polarity inversions show that these are c aused by large-scale folds in the magnetic field, rather than by opposite p olarity magnetic flux tubes originating near the sun.