between solar-cycle length and global temperature:
This evidence that much of 20th century warming might be explained by solar activity was a thorn in the side of the newly powerful CO2 alarmists, who blamed recent warming on human burning of fossil fuels. That may be why Lassen and Thejll were quick to offer an update
as soon as the 1997-98 El Nino made it look as if temperatures were suddenly skyrocketing:
The rapid temperature rise recently seems to call for a quantitative revisit of the solar activity-air temperature association …
We conclude that since around 1990 the type of Solar forcing that is described by the solar cycle length model no longer dominates the long-term variation of the Northern hemisphere land air temperature.
Study of the sun-climate link was energized in 1991 by Friis-Christensen and Lassen, who showed a