Ironically, today at this moment, there isn’t a single sunspot on the sun.
I think that they believe that this next peak sunspot cycle will be higher this next cycle (which is just about to begin) with a more rapid increase in the suspot numbers that has been observed before.
True.
Level of sunspot number is an indicator of the average irradiance of the sun, but you have to take an decade long average to mean anything, as you certainly know.
All sunspot cycles have times with no, or very few, sunspots, but the immediate solar irradiance doesn’t change with number of the sunspots. The sun would be cold right now if that were true. Even during the Maunder minimum, when there were very few sunspots seen for many decades at a time, the irradiance of the sun was definitely no lower than 99.5% of the present.
I’m beginning to see emerging in the scientific literature solar mechanisms which can account for changing solar irradiance cycles. In particular, there recently was published a proposed mechanism for the natural 100,000yr and 41,000yr cycles. There are defintely others in addition to the 11/22yr solar cycle, too.
At this time, I’m getting more and more convinced that cycles having to do with the sun and others (like earth’s ocean subsurface currents and the CO2 source/sink resulting from that, biological influences, etc.) are responsible for the bulk of the temperature changes on Earth, as well as most of the CO2 changes seen throughout history, including the most recent increase.