On the glacial-interglacial variability of the Asian monsoon in speleothem δ18O records.
TL;DR: It is found that the records close to the monsoon moisture source show large glacial-interglacial variability, which then decreases landward, the moisture transport pathway effect, which counteracts the forcing of glacial boundary conditions.
Abstract: While Asian monsoon (AM) changes have been clearly captured in Chinese speleothem oxygen isotope (δ18O) records, the lack of glacial-interglacial variability in the records remains puzzling. Here, we report speleothem δ18O records from three locations along the trajectory of the Indian summer monsoon (ISM), a major branch of the AM, and characterize AM rainfall over the past 180,000 years. We have found that the records close to the monsoon moisture source show large glacial-interglacial variability, which then decreases landward. These changes likely reflect a stronger oxygen isotope fractionation associated with progressive rainout of AM moisture during glacial periods, possibly due to a larger temperature gradient and suppressed plant transpiration. We term this effect, which counteracts the forcing of glacial boundary conditions, the moisture transport pathway effect.
Cites background from "On the glacial-interglacial variabi..."
...Evaluating climate proxy data (e.g. Liu et al., 2020; Yao et al., 2007) against paleoglacial reconstructions can reveal if glaciation on the Tibetan Plateau is most sensitive to changes in precipitation or temperature (e.g. Dortch et al., 2013)....
"On the glacial-interglacial variabi..." refers background in this paper
...(1000 + 18 O pi ) / (1000 + 18 O vi ) = (liquid‐vapor) (8)...
...However, variation in other major paleoclimate records, such as atmospheric CO2 concentration (blue) (6) and Antarctica surface temperature anomaly (red) (7) retrieved from European Project for Ice Coring in Antarctica (EPICA) Dome C ice core, benthic foraminifera 18O LR04 stack (purple) (8), and global sea surface temperature (SST) stack (orange) (9), are dominated by the ~100-kyr glacialinterglacial cycle....
...(G) Benthic foraminifera 18O LR04 stack (8)....