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Identification of Holocene climate events, their temporal and spatial characteristics, and their causal mechanisms are important for understanding past climate systems with implications for interpreting ancient cultural transformations. In this paper, we analyse globally-distributed, high-resolution climate proxy records from 58 sites to develop a comprehensive understanding of climate change around 7.2 ka BP. Analysis of the data compilation, which comprises records from lake sediments, one loess section, speleothems, marine sediments, and ice cores, show that the climate event is manifested as a weakening of the Asian summer monsoon and a strengthening of the South American summer monsoon. Climate change also involves dramatic cooling and wetter conditions in north-central Europe, widespread aridity across the Africa and west-south North America, contrasting patterns of precipitation variability throughout the Mediterranean, and notable cooling over the polar regions, suggesting that this is a global climate event. A close correspondence between the 7.2 ka event and the timing of solar irradiance minima, strong volcanic eruptions, meltwater flux into the North Atlantic Ocean, and an orbitally-induced decrease in summer solar insolation suggests a possible causal link with these phenomena. We suggest that climate anomalies around 7.2 ka BP may be specifically explained as a response to southward migration of the Intertropical Convergence Zone, onset of an increasingly El Niño-like state, reinforcement of the westerlies, and slowing of the Atlantic Meridional Overturning Circulation (AMOC). • The 7.2 ka event is well represented in 58 paleoclimatic records from the global. • Varying climatic responses are evidenced in different regions during 7.6–7.0 ka BP. • The 7.2 ka event arise of the atmosphere–ocean–land feedback in response to four forcing factors. [ABSTRACT FROM AUTHOR]

Artemisia and Chenopodiaceae are the two main pollen taxa in studies of lake sediments on the central and western Tibetan Plateau (TP). In this paper, we present Artemisia /Chenopodiaceae (A/C) ratios in pollen assemblages of surface sediments from 42 lakes on the central and western TP. Relationships between vegetation, climate and A/C ratio are investigated. The results show that the A/C ratio in the study region can distinguish desert from steppe vegetation. As a whole, the A/C ratio was higher than 1.2 in the steppe vegetation and lower than 1.2 in the desert vegetation zone. Statistical analysis revealed that the A/C ratio can be used as a moisture indicator on the TP. Based on the A/C ratio in pollen assemblages of sediment core TAN12-2 from Lake Tangra Yumco, we reconstructed the vegetation and climate history of the southern TP during the transitional period from the late glacial to the Holocene (17.5–10 cal kyr BP). From 17.5 to 16 cal kyr BP, desert vegetation occurred and climate was extremely dry. During 16–15 cal kyr BP, desert was replaced by steppe vegetation and climate became wetter. From 15 to 10 cal kyr BP, the lake basin of Tangra Yumco was covered by the steppe vegetation and climate tended to be more humid. Comparing our results with other lacustrine records on the TP, we found that the Indian summer monsoon (ISM) significantly affected the southern TP earlier than the northeastern TP. [ABSTRACT FROM AUTHOR]