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Recent climate and environment over the Tibetan Plateau (TP) have undergone significant changes, dominated by variations in the Westerlies and the Indian summer monsoon. However, long‐term shifts in atmospheric circulation during the transitional seasons are still lacking. Here we investigate the modern distribution of Tsuga pollen over the central‐western TP and confirm it as an indicator of variable atmospheric circulation in spring. By combining our Tsuga record from Taro Co with existing records in the Tsuga pollen source area, we suggest that a potential particle transport pathway from the southern slope of the Himalayas to the interior of the plateau appeared in the spring of the late Holocene. Our results show that the springtime atmospheric circulation over the southwestern TP during the early and late Holocene is closely related to the substantial remnants of ice sheets at northern high latitudes and the frequency of El Niño events, respectively. Plain Language Summary: The spring climate over the Tibetan Plateau (TP) is undergoing significant changes that yield profound impacts on environmental changes such as variations in vegetation phenology and alpine treeline. Knowledge of long‐term variations in atmospheric circulation during spring can improve the understanding of current climatic and environmental change and the projection of future variability. In this paper, we use an exotic pollen grain, which can be transported long distances in the air, as an indicator to trace the variability of spring atmospheric circulation over the TP. The results indicate that the spring meridional atmospheric circulation from the southern slope of the TP to its interior has been enhanced in the last four thousand years, which is mainly influenced by the frequency of El Niño events. Key Points: Spring atmospheric circulation change over the southwestern Tibetan Plateau (TP) during Holocene is reconstructedMeridional atmospheric circulation in spring over the southwestern TP is strengthened in the late HoloceneHigh‐(low‐) latitude forcing mainly influence the variations in spring atmospheric circulation during the early (late) Holocene [ABSTRACT FROM AUTHOR]

A palynological assay of the studies carried out from the Western and the Eastern Himalaya (India) during the Late Pleistocene and Holocene is presented here. The Western Himalaya is affected by both the Indian Summer Monsoon (ISM) and Western Disturbances, whereas the Eastern Himalaya receives precipitation only from the ISM. During the Late Pleistocene (~77 ka), a cold and arid climate supported steppe vegetation in the Western Himalaya. In the Eastern Himalaya, around 66 ka, a cool and dry climate supported the savannah vegetation with few scattered trees of Pinus and Tsuga. A number of warm-moist fluctuations are also perceptible during the Late Pleistocene. The impacts of Last Glacial Maximum, Holocene Climatic Optimum, Medieval Warm Period and Little Ice Age are well discernible in the vegetation in both the regions. Within a broad similarity, the climate change and associated vegetation succession varied from region to region; as the palynological records are characterized by the evidences of prolonged humid phases in the eastern sector, whereas the arid events are better marked in the western part. The similarities and incompatibilities in the climate and vegetation between the Western and Eastern Himalaya during the Late Pleistocene and Holocene are discussed in the present paper. [ABSTRACT FROM AUTHOR]