Evidence for Solar Modulation on the Millennial-Scale Climate Change of Earth

Abstract

In this study, we use available reconstructed data to investigate periodicities of solar activity (i.e., sunspot number) and the Earth’s climate change (temperatures of Lake Qinghai in China and Vostok in Antarctica, the GISP δ18O climate record of Greenland, and the stalagmite δ18O monsoon records of Dongge Cave in China) as well as their cross-wavelet coherences on millennial scale. We find that the variations of the Earth’s climate indices exhibited the 1000-year cyclicity, which was recently discovered in solar activity (called Eddy cycle). The cross-wavelet correlations between the millennium-cycle components of sunspot number and the Earth’s climate change remains both strong and stable during the past 8640 years (BC 6755–AD 1885). The millennial variation of sunspot number keeps in-phase with variations of Lake Qinghai temperature, Greenland temperature, and East Asian Monsoon, but anti-phase with the variation of Antarctica temperature. The strong and stable resonant relationships between sunspot numbers and these climate indices indicate that solar variability may have played a role in modulation on this millennial seesaw pattern of the Earth’s climate change before the modern industrial era.

Holocene Millennial-Scale Solar Variability and the Climatic Responses on Earth

“…We see that solar variability represented by SSN had a host of periodicities over the 95% confidence level, such as the 150-year cyclicity, 200-year cyclicity (Suess-de Vries cycle [31]), 350-year cyclicity, 500-year cyclicity, millennial cyclicity (990 years and 1149 years) (Eddy cycle [9,[32][33][34]). Similar results were found in our previous study [16]. On the other hand, the temperatures had relatively fewer significant periodicities.…”

“…In this paper, we will explore the relations between solar variability and temperature changes for a more widely distributed database on Earth in order to check and expand our previous conclusions. This is an expanded follow-up of our last work [16].…”

“…For these 73 globally distributed temperature records used in Marcott et al [16], we selected data for our analysis based on the following criteria: (1) covering the period BC 6755-AD 1885; (2) the time resolution higher than or about 100 years; (3) temperature coming from a single site, not composite ones. In this way we obtained temperature data of 10 sites (T 1~T10 ) distributed from the Arctic to the Antarctic, i.e., temperatures of Agassiz-Renland, Tsuolbmajavri Lake, RAPID-12-1K, OCE326-GGC30, MD98-2181, ODP_1084B, TN057-17, Homestead Scarp, Dome C, and Vostok.…”

“…We adopted the same analytical methods as those in our previous work [16]. We used the Lomb-Scargle periodogram method [28,29] to analyze periodicities of both solar variability and temperature change on Earth.…”

“…For example, Marcott et al [15] provided a wider view by reconstructing both regional and global temperatures for the past 11,300 years from 73 globally distributed sites. We found some clues about the evidence of solar modulation on the Earth's climate change on a millennial scale in our last work [16], but the adopted climatic indicators were limited only to four local places on Earth (i.e., Greenland, Lake Qinghai and Dongge cave in China, Vostok in Antarctica). In this paper, we will explore the relations between solar variability and temperature changes for a more widely distributed database on Earth in order to check and expand our previous conclusions.…”