No Solar Signal in Temperature Proxies from Antarctica

Abstract

We analyzed a number of Antarctic climatic proxies including: 1) an annual proxy covering the time interval 1800-2003, 2) four low-resolution (tens to hundreds of years) ice core records covering the last 242,000 years. The main goal of the work was to search for traces of solar influence on Antarctic climate. Both Fourier and wavelet approaches were used in the statistical analyses. We found no evident fingerprints of solar cycles of Schwabe (ca 11 years), Hale (ca 22 years), Gleissberg (century-scale) or Hallstatt (ca 2000 years). Instead a strong variation with period ca 9800 - 11,600 years is present in the long temperature proxies during the last 242,000 years. It was shown that this variation likely was the result of varying CO 2 concentration in the atmosphere, although some solar influence cannot be fully excluded. No features of a quasi 10,000 year variation were found in the Greenland δ 18 O record. The results show that solar-climatic relationship in Antarctica is weaker than in the high-latitude areas of the Northern Hemisphere.