A paper published today in Journal of Atmospheric and Solar-Terrestrial Physics finds a “strong and stable correlation” between the millennial variations in sunspots and the temperature in Antarctica over the past 11,000 years. In stark contrast, the authors find no strong or stable correlation between temperature and CO2 over that same period.
The authors correlated reconstructed CO2 levels, sunspots, and temperatures from ice-core data from Vostok Antarctica and find
“We find that the variations of SSN [sunspot number] and T [temperature] have some common periodicities, such as the 208 year (yr), 521 yr, and ~1000 yr cycles. The correlations between SSN and T are strong for some intermittent periodicities. However, the wavelet analysis demonstrates that the relative phase relations between them usually do not hold stable except for the millennium-cycle component. The millennial variation of SSN leads that of T by 30–40 years, and the anti-phase relation between them keeps stable nearly over the whole 11,000 years of the past. As a contrast, the correlations between CO2 and T are neither strong nor stable.”
Thus, the well known ~1000 year climate cycle responsible for the Holocene Climate Optimum 6000 to 4000 years ago, the Egyptian warm period ~4000 years ago, the Minoan warm period ~3000 years ago, the Roman warm period ~2000 years ago, the Medieval warm period ~1000 years ago, and the current warm period at present all roughly fall in this same 1000 year sequence of increased solar activity associated with warm periods.
The authors find temperature changes lag solar activity changes by ~40 years, which is likely due to the huge heat capacity and inertia of the oceans. Warming proponents attempt to dismiss the Sun’s role in climate change by claiming 20th century solar activity peaked at around 1960 and somewhat declined from 1960 levels to the end of the 20th century (and have continued to decline in the 21st century right along with the 18+ year “pause” of global warming).
Abstract
The solar impact on the Earth’s climate change is a long topic with intense debates. Based on the reconstructed data of solar sunspot number (SSN), the local temperature in Vostok (T), and the atmospheric CO2 concentration data of Dome Concordia, we investigate the periodicities of solar activity, the atmospheric CO2 and local temperature in the inland Antarctica as well as their correlations during the past 11,000 years before AD 1895. We find that the variations of SSN and T have some common periodicities, such as the 208 year (yr), 521 yr, and ~1000 yr cycles. The correlations between SSN and T are strong for some intermittent periodicities. However, the wavelet analysis demonstrates that the relative phase relations between them usually do not hold stable except for the millennium-cycle component. The millennial variation of SSN leads that of T by 30–40 years, and the anti-phase relation between them keeps stable nearly over the whole 11,000 years of the past. As a contrast, the correlations between CO2 and T are neither strong nor stable. These results indicate that solar activity might have potential influences on the long-term change of Vostok’s local climate during the past 11,000 years before modern industry.
Secondly, this paper finds strong evidence of a 30-40 year lag between solar activity and temperature response. So what happened ~40 years after the 1960 peak in sunspot activity? Why that just so happens to be when satellite measurements of global temperature peaked with the 1998 El Nino [which is also driven by solar activity], followed by the “pause” and cooling since.
We have thus shown
Strong correlation between solar activity and climate over the past 11,000 years of the Holocene
Strong lack of correlation between CO2 and climate over the past 11,000 years of the Holocene
Solar activity explains all 6 well-known warming periods that have occurred during the Holocene, including the current warm period
The 20th century peak in sunspot activity is associated with a 40 year lag in the peak global temperature
