From Co2Science: In the words of Huang et al. (2020), “millennial- and centennial-scale climate observations over the entire Holocene in arid northwest China are poorly characterized and understood,” adding that “more high-resolution records from arid central Asia, especially of temperature, are needed to better understand regional climatic variability.” What is more, it is essential that scientists understand regional characteristics of natural climatic variability in order to be able to correctly determine if rising concentrations of greenhouse gases are measurably impacting present-day climate.

Paper reviewed: Huang, C., Rao, Z., Li, Y., Yang, W., Liu, L., Zhang, X. and Wu, Y. 2020. Holocene summer temperature in arid central Asia linked to millennial-scale North Atlantic climate events and driven by centennial-scale solar activity. Palaeogeography, Palaeoclimatology, Palaeoecology 556: 109880, doi.org/10.1016/j.palaeo.2020.109880.

So it was that against this backdrop the team of seven Chinese researchers developed a long-term (11,000 year) high-resolution record of historic summer temperatures from an alpine peat core obtained from the Altai Mountains. Then, they performed a series of statistical analyses to determine millennial- and centennial-scale periodicities in their record, while also analyzing similarities between their historic proxy and other long-term climatic records and potential climatic drivers.

Results of the study revealed the Altai peat cellulose record is “a reliable indicator of summer temperature,” showing both a long-term warming trend and multiple short-duration warm/cold excursions. With respect to the cause of these temperature excursions Huang et al. write “our data show that the Holocene summer temperature variations are roughly synchronous with solar activity, with high (low) summer temperature corresponding to strong (weak) solar activity, and that there are several common periodicities in both summer temperature and solar activity,” particularly periodicities that correspond to the well-known Gleissberg and Suess solar cycles. Consequently, the researchers affirm “solar activity was the fundamental driver of the centennial-scale variability of summer temperature in arid central Asia during the Holocene.” Given such an affirmation, researchers would perhaps do well to spend more time researching the influence of the Sun on current temperature/climate than anthropogenic greenhouse gases.