Three articles, the first by Tallbloke in the light of the recent heatwave:
Over the 11-year solar cycle, the sun’s heat and visible light fluctuate, as does its production of invisible UV, which varies much more than the tenth of a percent change in total solar output. It’s thought that changes in solar UV irradiance cause wind shifts in the stratosphere (the layer of the atmosphere above the troposphere), which in turn induce blocking in the tropospheric jet stream via a feedback effect.
Blocking can also stem from other mechanisms. In the North Atlantic at least, a 2008 research paper found that during periods of low solar activity, blocking events in more eastward locations are longer and more intense than during higher solar activity.
Right now we’re entering a stretch of diminished solar output, signified by a falloff in the average monthly number of sunspots as depicted in the next figure.
The decline in the maximum number of sunspots over the last few cycles likely heralds the onset of a grand solar minimum, which could usher in a period of global cooling.
The second is by Eric Worrall:
The third by Charles Rotter: