Quantitative reconstruction of the relative humidity by a coupled δ18O-δ2H approach during the Younger Dryas in central China
Quantitative reconstruction of the relative humidity by a coupled δ18O-δ2H approach during the Younger Dryas in central China
复制标题
耦合δ18O-δ2H方法定量重建中国中部新仙女木期相对湿度
DOI：
10.1016/j.quascirev.2022.107879
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发表时间：
2023
影响因子：
4
通讯作者：
Xianyu Huang
中科院分区：
文献类型：
--
作者：
Yang Yang;Yaru Zhang;Hongbin Zhang;Xianyu Huang
全新世中国中部地区与北方和南方的水文气候变化具有不同步性。这种空间模式是否适用于新仙女木事件（YD），从末次冰期到全新世的过渡期间的一个突出的气候突变，是缺乏约束的定量记录。本文应用新的叶蜡正构烷烃氢同位素组成和半纤维素氧同位素（δ 2 Hn-alkane-δ 18 Osugar）耦合的古湿度计方法，重建了中国中部大九湖泥炭地13.1- 10.0calkaBP泥炭层的古相对湿度（RH）。δ 2 H正构烷烃-δ 18 O糖耦合模型揭示了12.7-12.1 cal ka BP期间相对湿度较低（RH avg. 79%，1σ 4.9%），然后在12.1-11.7 cal ka BP（RH平均）期间转向相对高值。88.6%，1σ 3.9%）。在YD末至11.3calkaBP（相对湿度< 80%）出现了一个干燥期。与北方和南方的普遍干旱相反，中国中部地区在YD期间的总体湿润趋势。在夏季风强度较弱的背景下，西风带与东亚夏季风的相互作用可能导致了YD期间中国中部地区的增湿趋势。
Paleoclimate records in central China reveal asynchronous hydroclimate changes to those from both northern and southern China during the Holocene. Whether such a spatial mode works for the Younger Dryas event (YD), a prominent abrupt climate change during the transition from the last glacial to the Holocene, is poorly constrained by quantitative records. In this study, we apply the novel coupled hydrogen isotope composition of leaf waxn-alkanes and oxygen isotope of hemicellulose (δ2Hn-alkane-δ18Osugar) paleohygrometer approach to reconstruct the paleo relative humidity (RH) on a peat layer spanning 13.1–10.0 cal ka BP in the Dajiuhu peatland, central China. The coupled δ2Hn-alkane-δ18Osugarapproach reveals that the RH was relatively low in the period of 12.7–12.1 cal ka BP (RH avg. 79%, 1σ 4.9%) and then turned to relatively high values during 12.1–11.7 cal ka BP (RH avg. 88.6%, 1σ 3.9%). A dry interval happened from the end of the YD to 11.3 cal ka BP (RH< 80%). A general wetting trend during the YD period in central China contrasts with the prevailing drying in northern China and maybe also in southern China. The occurrence of a wetting trend during the YD period in central China probably results from the interplay between the westerlies and the East Asian summer monsoon under a context with weak summer monsoon intensity.