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In this study, the compiled malacological record of the two most important loess–palaeosol sequences (LPS) in Serbia was used to reconstruct the Malacothermometer July Paleotemperature (MTJP) of the last nine glacials. The sieved loess samples yielded shells of 11 terrestrial gastropod species that were used to estimate the MTJP. Veliki Surduk (covering the last three glacial cycles) and Stari Slankamen (covering the last fourth to ninth glacial cycle) LPSs previously lacked the malacological investigations. After the sieving, a total of 66,871 shells were found, from which 48,459 shells were used for the estimation of the MTJP. Through the studied period, the reconstructed MTJP was ranging from 14.4 °C to 21.5 °C. The lowest temperature was recorded during the formation of the loess unit L5, equivalent to the Marine Isotope Stage (MIS) 12. The second-coldest summers were occurring during the MIS 16 glacial. Although the warmest glacial was L8 (MIS 20) according to MTJP, these July temperatures might be overestimated due to only two samples from the poorly preserved L8 unit. The malacological material derived from the loess units at Veliki Surduk and Stari Slankamen LPSs showed great potential for July temperature reconstruction, as the comparison with other regional records showed similar climate changes. Further work is necessary to validate the age scale of the oldest samples, and a higher resolution sampling could lead to more detailed July temperature fluctuations, as was shown for the youngest glacial in this study. Likewise, estimating the July temperature using different proxies (e.g., pollen) from the same LPSs could be used to confirm the observed climate trends. [ABSTRACT FROM AUTHOR]

The westerlies play an important role in driving climate change in the Tibetan Plateau (TP). However, little is known about the history of the westerlies in the TP owing to limited observations and a lack of robust reconstructions. The widely distributed eolian loess in the eastern TP is one of the ideal materials to retrieve the intensity history for the westerlies. A detailed grain-size and endmember model analysis (EMMA) on the Ganzi loess sequence located in the eastern TP revealed that the EMMA decomposed the loess grain-size components into four endmembers: EM1 (modal size 1.42 μm) is related to pedogenesis, and EM2 (modal size 7.10 μm) is transported by the westerlies. Silt modes (EM3 and EM4) are transported by the TP winter monsoon or near-surface airflows. The mass accumulation rate (MAR) of EM2 indicated the westerly variations. Combined with the MAR, we reconstructed the history of westerly intensity since the last interglacial period from the Ganzi loess sequence. We found that the intensity of the westerlies showed typical glacial/interglacial variations since the last interglacial period in the eastern TP. The westerly intensity was strong with large fluctuations during the glacial period, whereas it was weak and stable during the Holocene and the last interglacial. The temperature gradient between high and low latitudes caused by changes in insolation and ice volume in the northern hemisphere were the dominant forcing mechanisms for the westerly intensity variations. [ABSTRACT FROM AUTHOR]