Astronomers Take the Heat Out of Sunspots Theory

New analysis of records stretching back 400 years to the observations of Renaissance scientist Galileo shows that global warming is not the result of solar activity.

Forget the sunspot connection.  Scientists say that rising global average temperatures cannot be attributed to them as there has been no long-term upward trend in solar activity since 1700.

An international team of astronomers looked at the historical records again, and have concluded that the collected data have  been telling a confusing story.  And while conclusions in science tend to be provisional, and repeatedly challenged, this latest pronouncement comes from heavyweights.

Astronomers have been counting and recording sunspots – transient dark patches on the face of the sun – since Galileo turned his homemade telescope on the heavens 400 years ago. But, historically, there have been two ways of counting and recording sunspots − and the two sets of records have differed.

Now Frédéric Clette, director of the World Data Centre of the Sunspot Index and Long-Term Solar Observations at the Royal Observatory of Belgium, Leif Svalgaard, a solar physicist at Stanford University, California, and Ed Cliver, of the US National Solar Observatory in California, have presented their findings at the 29th general assembly of the International Astronomical Union in Honolulu, Hawaii.

Data discrepancies
They recalibrated some discrepancies that existed in the two sets of historical records, and now both sets of data tell the same story:  the sun hasn’t been getting busier in the last two centuries or so.

The sunspot cycle has gone on showing a pattern of change every 11 years or so, but the long-term trend is unchanged.  The contribution of recent solar activity to recent global warming has remained unchanged.

Read more at Astronomers Take the Heat Out of Sunspots Theory