Shift of large-scale atmospheric systems over Europe during late MIS 3 and implications for Modern Human dispersal

Abstract

Understanding the past dynamics of large-scale atmospheric systems is crucial for our knowledge of the palaeoclimate conditions in Europe. Southeastern Europe currently lies at the border between Atlantic, Mediterranean, and continental climate zones. Past changes in the relative influence of associated atmospheric systems must have been recorded in the region’s palaeoarchives. By comparing high-resolution grain-size, environmental magnetic and geochemical data from two loess-palaeosol sequences in the Lower Danube Basin with other Eurasian palaeorecords, we reconstructed past climatic patterns over Southeastern Europe and the related interaction of the prevailing large-scale circulation modes over Europe, especially during late Marine Isotope Stage 3 (40,000–27,000 years ago). We demonstrate that during this time interval, the intensification of the Siberian High had a crucial influence on European climate causing the more continental conditions over major parts of Europe, and a southwards shift of the Westerlies. Such a climatic and environmental change, combined with the Campanian Ignimbrite/Y-5 volcanic eruption, may have driven the Anatomically Modern Human dispersal towards Central and Western Europe, pointing to a corridor over the Eastern European Plain as an important pathway in their dispersal.

Eolian dust dispersal patterns since the last glacial period in eastern Central Asia: insights from a loess-paleosol sequence in the Ili Basin

“…7). Glaciers in the region expanded during early and late MIS3 (Owen and Dortch, 2014). The apparent chronological link between increased primary loess accumulation and glacial expansion in the region contrasts with trends elsewhere indicating increased dust accumulation during dry and windy glacial conditions, and pedogenesis under comparatively wetter interglacial conditions (Ding et al, 2002;Dodonov and Baiguzina, 1995;Stevens et al, 2013;Sun et al, 2010).…”

“…Although the influence of the Siberian High has been shown to decrease westward from the CLP (Vandenberghe et al, 2006), wind strength and frequency over the Aral Sea in western central Asia during the Holocene was nevertheless associated with the intensity of the Siberian High pressure system (Feng et al, 2011;Sorrel et al, 2007). Obreht et al (2017) even hypothesized increased influence of the Siberian High during MIS 3 over the Lower Danube Basin in SE Europe, although this has yet to be substantiated. Moreover, the Siberian High was considered to be one of the most important influences on dust deposition based on the results of long-term monitoring over Central Asia between 2003 and 2010 (Groll et al, 2013).…”

“…The large, cold Siberian High pressure system is at the north-northeast of our study area, centering between 40 and 65 • N and between 80 and Comparison between EM1 grain size variability and the timing of glacial advances in the Tian Shan (Koppes et al, 2008;Owen and Dortch, 2014); stable oxygen isotope variations from the Greenland ice cores (Rasmussen et al, 2014); mean grain size (MGS) record of the Jingyuan loess section from the CLP (Sun et al, 2010) and; U-ratio (15.6-63.4 µm / 5.61-15.6 µm) of the SE Kazakhstan loess (Machalett et al, 2008). A five-point running average was performed for the intervals with higher sedimentary rate on EM1 curve (red line).…”

“…S4 and Table S1 in the Supplement). We assessed the degree of correlation between wind strength variability in the Ili Valley (NLK), as represented by the proportions of EM1, with the stable oxygen isotope record from the Greenland ice cores representing North Atlantic paleoclimate (Rasmussen et al, 2014), the mean grain size (MGS) record of the Jingyuan loess section from the CLP (Sun et al, 2010), uranium (U) ratio (15.6-63.4 µm / 5.61-15.6 µm) of the Remizovka loess section in SE Kazakhstan (Machalett et al, 2008), and glacial advances in the Tian Shan (Koppes et al, 2008;Owen and Dortch, 2014) (Fig. 7).…”

“…3 in Huang et al, 2011). The Siberian anticyclone dominates winter and spring climate over Eurasia (Gong and Ho, 2002;Obreht et al, 2017;Panagiotopoulos et al, 2005;Sahsamanoglou et al, 1991). Although the influence of the Siberian High has been shown to decrease westward from the CLP (Vandenberghe et al, 2006), wind strength and frequency over the Aral Sea in western central Asia during the Holocene was nevertheless associated with the intensity of the Siberian High pressure system (Feng et al, 2011;Sorrel et al, 2007).…”