solar minimum image
© NASA
During a solar minimum, certain types of activity, such as sunspots and solar flares will drop - but NASA also expects the development of long-lived phenomena including coronal holes.

The sun's magnetic field weakens during solar minimums, thus providing less shielding to the earth. With our protective shield thus weakened, the number of galactic cosmic rays that reach the earth's upper atmosphere increases.

The video is from NASA.