...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of paleolimnology >A 16-ka δ~(18)O record of lacustrine sugar biomarkers from the High Himalaya reflects Indian Summer Monsoon variability
【24h】

A 16-ka δ~(18)O record of lacustrine sugar biomarkers from the High Himalaya reflects Indian Summer Monsoon variability

机译：

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We investigated a late glacial–Holocene lacustrine sediment archive located at 4,050 m a.s.l. in the small carbonate-free catchment of Lake Panch Pokhari, Helambu Himal, Nepal. A δ~(18)O sugar biomarker record was established by applying novel compound-specific δ~(18)O analysis of plant sugar biomarkers (Zech and Glaser in Rapid Commun Mass Spectrom 23:3522–3532, 2009). This method overcomes analytical challenges such as extraction and purification faced by previous methods aimed at using δ~(18)O of aquatic cellulose as a paleoclimate proxy. The δ~(18)O results for sugar biomarkers arabinose, xylose and fucose agree well and reveal a pronounced trend towards lower δ~(18)O values during the deglaciation and the onset of the B?lling/Aller?d interstadial. By contrast, the period of the Younger Dryas is characterized by higher δ~(18)O values. The early Holocene again reveals lower δ~(18)O values. We suggest that our lacustrine δ~(18)O record reflects coupled hydrological and thermal control. It is strongly related to changes in the oxygen isotopic composition of paleo-precipitation and resembles the δ~(18)O records of Asian speleothems. With respect to the ‘amount effect,’ the record is interpreted as reflecting the Indian Summer Monsoon intensity. The precipitation signal is, however, amplified in our record by evaporative 18Oenrichment that is controlled by the ratio of precipitation to evaporation. We suggest that our δ~(18)O record reflects the variability of the Indian Summer Monsoon, which was strong during the B?lling/Aller?d interstadial and early Holocene, but weak during the Younger Dryas stadial. This interpretation is corroborated by a pollen-based index for Lake Panch Pokhari that estimated the strength of the Indian Summer Monsoon versus the strength of the Westerlies. Millennial-scale synchronicity with the Greenland δ~(18)O temperature records highlights the previously suggested strong teleconnections between the Asian Monsoon system and North Atlantic climate variability.

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号