Hi Mike

sunpots are in fact one sign of changes in the sun's magnetic field that are happening much lower down, below the sun's surface.

When a sunspot grows, a tube of strongly magnetic gas is rising up through the sun's surface. The cross-section (which is the area through the middle) of this tube initially gets bigger as the tube rises (so the spot grows) . But once it has sat around for a while in the turbulent solar atmosphere, the flows start to pull it apart, and it starts to disintegrate and shrink.