Monday, February 15, 2010

Cosmic Rays v. Inverse Solar Magnetic Activity


Related to the prior post Cosmic Rays 'Off the Chart', plotting the monthly neutron cosmic ray counts from the Oulu Finland monitoring station v. the "inverse" solar magnetic activity (30-smoothed Ap Index) shows close linear agreement (R² =.99). Indeed, the current quiestest & longest solar minimum in modern history is accompanied by an increase in cosmic ray counts to the highest in recorded history. An increase in cosmic rays increases cloud nucleation and hence cooling due to reflection of the sun's rays (albedo)(Svensmark & others). Here is evidence that small changes in solar activity of only typically 0.1% TSI from peak to trough of solar cycles can be amplified by the effect of cosmic rays on secondary albedo. Cloud cover also appears to be linearly related to cosmic rays, and global cloud cover is in turn linearly inversely related to global temperature. Note that during the last solar minimum in 1998, cosmic ray counts hit a maximum of 6579, but during the current "record" solar minimum, cosmic ray counts hit a maximum of 6843 in December 2009 (4% higher). The TSI bottomed at 1365.4 between solar cycle 22 & 23 and at 1365.2 between 23 & 24, only a 0.01% decrease, yet an amplified 4% increase in cosmic ray flux resulted, potentially resulting in a ~4% decrease in temperature assuming the linear relationships noted above (interesting that there has been around a 3% global cooling since the peak of cycle 23).
The IPCC AR4 model of radiative forcing from solar irradiation does not take into account the "Svensmark factor", which theorizes that small changes in solar activity are amplified due to the secondary effects on cosmic rays & cloud cover. The IPCC model assigns what appears to many to be an absurdly low value (only 7% of the positive forcing "arbitrarily" assigned to CO2) to radiative forcing from solar irradiation without consideration of these potentially amplified secondary effects. 

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