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The evolution of global temperature during Holocene is crucial for understanding the mechanisms of climate change and future climate trends. However, there is a discrepancy between the temperature trends reconstructed from proxy and model, which is attributed to the seasonal biases and the appearance of the Holocene thermal maximum was dominated by the temperature of the warm season. In this paper, fossil charcoal assemblages from the southern Chinese Loess Plateau were analysed to provide quantitative mean annual temperatures (MAT) and four-season temperature records during 6.55–3.45 cal ka BP. The results indicate that both the seasonal temperatures and MAT during the middle Holocene reached warm peaks between 5.55 and 5.35 cal ka BP. The similar trend between the winter temperature (WIT) and MAT denotes the highest contribution of WIT changes to the MAT in the study area since the mid-Holocene. • Flowering functional group was used to reconstruct spring-autumn temperature. • Nonhardy plants were used to reconstruct winter temperature. • Winter temperature contributed the most to the annual temperature since mid-Holocene. • Middle-Holocene temperature was not showing a long-term warming trend. [ABSTRACT FROM AUTHOR]

Abstract Fluctuations in glacier mass and volume are indicative of changes in the climate system. They also strongly affect regional climate and hydrology. In this paper, we explore possible relationships between the radial growth of Schrenk spruce (Picea schren kiana Fisch. et Mey) and the mass balance of the Tsentralniy Tuyuksuyskiy (TS. Tuyuksuyskiy) Glacier, which is located on the northern slopes of the Tianshan Mountains in arid central Asia. We attempt to reconstruct the historical mass balance variability of the TS. Tuyuksuyskiy glacier using tree-ring widths and stable carbon isotope chronologies. The reconstruction is able to explain 62.1% of the variance in the annual glacier mass balance record over the 1965–2014 calibration period. We also analyzed centennial mass balance variability and its linkages to climate change. The TS.Tuyuksuyskiy glacier has a negative annual mass balance in most years and, since 1968, has undergone the most rapid and longest melting process in the past 166 years. The mass balance change of the glacier is controlled by the combination of temperature and precipitation conditions. This study could be useful for more detailed glaciological, hydrological, and climatological assessments in this portion of the Tianshan Mountains. Highlights • The reconstruction of glacial changes using tree ring widths and stable carbon isotopes is reliable in arid central Asia. • The TS.Tuyuksuyskiy glacier has had a negative annual mass balance for most of the past 166 years. • The mass balance change of the glacier is controlled by the combination of temperature and precipitation. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage (MIS) 3 is the latest interstadial to be a significant period for paleoclimate research. The mild interstadial climate in MIS 3 can shed light on studies of the current warming period. However, it is uncertain whether or not the humidity in MIS 3 exceeds that in Holocene level, and forcing mechanisms of paleoclimate evolution remains controversial. In this paper, we use pollen and AMS 14C dating data of a sediment core Ailike-2019 (4.49 m) recovered from Lake Ailike, Xinjiang in arid central Asia, to reconstruct the vegetation and climate changes in Lake Ailike over the last 40,000 years. The results show that Lake Ailike region has been dominated by desert vegetation since the middle MIS 3. The vegetation coverage shows that climate was arid in the middle MIS 3 (40.2-33.2 cal kyr BP), ameliorated during the late MIS 3 (33.2-26.7 cal kyr BP) but still dry, extremely dry during MIS 2 (26.7-12 cal kyr BP), and relatively wet during Holocene (12-0 cal kyr BP). The climate in the Holocene was wetter than in the mid-late MIS 3 in Lake Ailike, which is generally consistent with the paleoclimate records from arid central Asia and Europe. This climate pattern might be attributed to amounts of vapor transported by the westerlies and Siberian high pressure. Low/high Northern Atlantic sea-surface temperatures (SSTs) induced by decreased/increased Northern Hemisphere summer insolation resulted in westerlies transporting less/more amount of vapor to the arid central Asia during MIS 3/Holocene. Meanwhile, intensified/weakened Siberian high pressure resulting from the expanding/melting of ice sheet might induce dry/wet climate conditions in the mid-late MIS 3/the Holocene. • Fossil pollen records from Lake Ailike reveal vegetation and climate history since the middle MIS 3. • The climate was significantly wetter in the Holocene than in the mid-late MIS 3 in Lake Ailike. • This climate pattern is in general agreement with that in arid central Asia and Europe. • Eurasian ice volume and Northern Atlantic SSTs might be the driving factors of effective moisture in arid central Asia. [ABSTRACT FROM AUTHOR]