Variations in Spring Atmospheric Circulation on the Southwestern Tibetan Plateau During Holocene Linked to High- and Low-Latitude Forcing

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 Nino events, respectively.

Automated summary

Recent changes in the climate and environment of the Tibetan Plateau have been influenced by variations in the Westerlies and the Indian summer monsoon. However, there is a lack of understanding regarding long-term shifts in atmospheric circulation during the transitional seasons. By studying the distribution of Tsuga pollen, researchers have identified it as an indicator of variable atmospheric circulation in spring. The results suggest the existence of a potential particle transport pathway from the southern slope of the Himalayas to the interior of the plateau during the late Holocene spring.