Approximately every 11 years, the magnetic field of the sun switches its polarity. This usually occurs during the part of the sun’s cycle known as the Solar Maximum. During the last solar magnetic field reversal in 2003, there were 17 major solar flare eruptions within three weeks including the record setting X-28 flare. In the current cycle the sun has so far had unusually low levels of activity, the weakest in at least 100 years. Since scientists have only been studying solar activity since the 1700s, we don’t know for sure how unusual the current pattern is relative to longer time spans, what it means, or what to expect next.
This video from NASA explains some of the cosmic effects expected to occur: