Sunspots, first observed by Galileo, normally follow an 11-year cycle. We are into a few years into (recorded) cycle number 24 but according to NASA it's looking rather underpowered. Nobody is certain exactly what the consequences will be, but one distinct possibility is a cold period; a previous low in solar activity, the Maunder minimum, is correlated with a brief Little Ice Age. Nobody really knows how this unusual solar weather pattern might interact with human-caused climate change. Previously, albeit somewhat controversially.
Solar physicists may have discovered why the Sun recently experienced a prolonged period of weak activity. Apparently it was just a faulty conveyor belt. The solar minimum of 2008 is gone but not forgotten.