Recently on CRI an article on Which Causes which out of Atmospheric Temperature and CO2 content? was posted, and this was circulated to other blogs and much interesting discussion ensued, particularly on TallBloke’s Talkshop. This discussion raised the Cycles in Sunspot Number Reconstruction for 11,000 Years article about C14 isotope ratio being used as a Solar Cycle Proxy and the question of the similarity of Be10 use as a proxy was asked. So here is an analysis of the Be10 data obtained from this source:
Solar Irradiance reconstruction from 10Be, World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program
NAME OF DATA SET: Holocene Total Solar Irradiance Reconstruction
LAST UPDATE: 11/2009 (Original Receipt by WDC Paleo)
CONTRIBUTORS: Steinhilber, F., J. Beer, and C. Fröhlich.
IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2009-133
At 9,370 years long, this time series compares to the 11,000 year C14 record. If both are reliable indicators of Solar Activity cycles, then we would expect some similarity in the cycles found. Firstly, the actual time series:
Some of the strong cycles periods found are very similar to those found in the C14 reconstruction, 351 years (352), 207 years (208), 104.7 years (104.3), 86.1 years (87.6 and 84.7). Some cycles are similar but no longer significant (around 500 years). The very long cycles are not confirmed, but remember that the time interval used here is a bit shorter.
Because the 207 year cycle is very strong, it is once again examined by use of a 3 cycle filter.
Just as in the case of the 208 year cycle in the C14 solar proxy, we have peaks occurring at around 1800 and 2000 and troughs at around 1700 and 1900. This clearly shows that the Sun was a contributing factor to temperature rises in the 20th century, and that its contribution for the next century will be towards cooling.
Graphs and analysis prepared using CATS.