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首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Recent changes in a remote Arctic lake are unique within the past 200,000 years
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Recent changes in a remote Arctic lake are unique within the past 200,000 years

机译:在过去的200,000年中,偏远的北极湖的最新变化是独特的

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摘要

The Arctic is currently undergoing dramatic environmental transformations, but it remains largely unknown how these changes compare with long-term natural variability. Here we present a lake sediment sequence from the Canadian Arctic that records warm periods of the past 200,000 years, including the 20th century. This record provides a perspective on recent changes in the Arctic and predates by approximately 80,000 years the oldest stratigraphi-cally intact ice core recovered from the Greenland Ice Sheet. The early Holocene and the warmest part of the Last Interglacial (Marine Isotope Stage or MIS 5e) were the only periods of the past 200,000 years with summer temperatures comparable to or exceeding today's at this site. Paleoecological and geochemical data indicate that the past three interglacial periods were characterized by similar trajectories in temperature, lake biology, and lakewater pH, all of which tracked orbitally-driven solar insolation. In recent decades, however, the study site has deviated from this recurring natural pattern and has entered an environmental regime that is unique within the past 200 millennia.
机译:北极目前正经历着巨大的环境变化,但是,与长期的自然变化相比,这些变化如何仍是未知之数。在这里,我们展示了加拿大北极地区的湖泊沉积物序列,记录了过去20万年(包括20世纪)的温暖时期。该记录为从北极和格陵兰冰原中发现的最古老的地层完整的冰芯(大约有80,000年的历史)之前北极的近期变化提供了一个观点。过去的200,000年中,仅有全新世早期和最后一次冰间期的最暖部分(海洋同位素阶段或MIS 5e),夏季温度可与该地点相媲美或超过今天。古生态学和地球化学数据表明,过去三个冰间期的特征是温度,湖泊生物学和湖泊水的pH值具有相似的轨迹,所有这些轨迹都跟踪轨道驱动的日照。然而,在最近的几十年中,研究地点已经偏离了这种反复发生的自然形态,并进入了过去200年来独一无二的环境制度。

著录项

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  • 作者单位

    Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80309;

    Geology Department, University at Buffalo, Buffalo, NY 14260;

    Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E3;

    Department of Geosciences, University of Massachusetts, Amherst, MA 01003;

    Paleoecological Environmental Assessment and Research Laboratory, Department of Biology, Queen's University, Kingston, ON, Canada K7L 3N6;

    Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80309 Department of Geological Sciences, University of Colorado, Boulder, CO 80309;

    Paleoecological Environmental Assessment and Research Laboratory, Department of Biology, Queen's University, Kingston, ON, Canada K7L 3N6;

    Geology Department, University at Buffalo, Buffalo, NY 14260;

    Paleoecological Environmental Assessment and Research Laboratory, Department of Biology, Queen's University, Kingston, ON, Canada K7L 3N6;

    Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E3;

  • 收录信息 美国《科学引文索引》(SCI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    chironomids; climate change; diatoms; paleolimnology; polar;

    机译:手足动物气候变化;硅藻古脂学极性;

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