the connection between the sun's output and the jet stream is not on a "how bright is it shining?" level, but on an ultraviolet radiation level. and, it has to do with how the ultraviolet energy spreads out as it hits the earth, on an angle.

so, while breaking the correlation between temperatures and solar output after 1980 was key in determining the relationship between carbon emissions and a warming climate, pointing to ssw when the sun is down at the north pole doesn't quite work out so well - because fluctuations in ultraviolet radiation happen nonetheless, and act at the place where they hit the surface.

those warm temperatures at the geographic north pole migrated in with weather systems from further south.