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通过温暖的大西洋水向北极进行现代热传输的增强
Robert F Spielhagen1, Kirstin Werner, Steffen Aagaard Sørensen
1Academy of Sciences, Humanities, and Literature, 53151 Mainz, Germany. rspielhagen@ifm-geomar.de
Science (New York, N.Y.)
|January 29, 2011
概括
进入北冰洋的大西洋水温处于2000年来的最高水平. 这种前所未有的变暖与北极扩大全球变暖有关,影响了海冰的分布.
科学领域:
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
- 北极研究 北极研究
背景情况:
- 北极地区的变暖速度快于全球其他地区.
- 北流的大西洋水是北极热量转移和海冰分布的主要驱动因素.
- 大西洋水变化的历史记录仅限于大约150年.
研究的目的:
- 重建过去2000年来北极地区海洋温度变化的多十年级记录.
- 了解大西洋水的自然变化及其对北极气候系统的影响.
- 在长期气候变化背景下评估最近的温度趋势.
主要方法:
- 在西斯瓦尔巴德 (79°N) 收集的海洋沉积物核心的分析.
- 过去海洋温度的古海洋学重建.
- 沉积物数据与历史气候记录的相关性.
主要成果:
- 建立了2000年海洋温度变化的记录.
- 21世纪初进入北冰洋的大西洋水的温度在2000年的记录中是前所未有的.
- 最近的变暖趋势可能与北极地区的全球变暖放大有关.
结论:
- 该研究为了解北极气候变化提供了关键的长期背景.
- 与过去两千年相比,目前进入北极的大西洋水温异常高.
- 这些发现凸显了全球变暖对北极气候系统和海冰的影响.
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