Glacial fluctuations over the last 3500 years reconstructed from a lake sediment record in the northern Tibetan Plateau

Abstract

Reconstructing glacial fluctuations can provide insights into glacial variations in response to climate change and can help predict future glacial changes in the context of global warming. Here, we use an ~2-yr-resolution record of inert elements derived from a sediment core from Tian'E Lake in the northern Tibetan Plateau, together with proxies for magnetic susceptibility and n-alkanes, to reconstruct fluctuations of the Qiyi Glacier over the last 3500 years. Eight major glacial advances can be identified at 1450–1250 BCE, 1100–800 BCE, 250–100 BCE and 200–300 CE, 600–700 CE, 1250–1350 CE, 1600–1750 CE, and 1850–1950 CE. These glacial advances coincided with cold intervals, such as the Neoglaciation and the Little Ice Age, suggesting often mentioned temperature controls on glacial-mass variations in the past. Moreover, due to the wet-cold climate combinations in the Westerlies-dominated areas, these intervals can also be correlated with wet conditions, as revealed by previously reported carbonate contents, total organic carbon levels and Artemisia/Amaranthaceae ratios from the same lake. These results indicate that humid environments can also contribute to glacial advances in the northern Tibetan Plateau. Our study reveals a series of high-magnitude multi-decadal to multi-centennial-scale glacial fluctuations during the late Holocene and suggests that wet conditions can also facilitate glacial advances in the Westerlies-dominated regions such as the northern Tibetan Plateau.